WPS5711 Policy Research Working Paper 5711 Trade Liberalization, Firm Heterogneity, and Wages New Evidence from Matched Employer-Employee Data Pravin Krishna Jennifer P. Poole Mine Zeynep. Senses The World Bank Development Research Group Trade and Integration Team June 2011 Policy Research Working Paper 5711 Abstract In this paper, the authors use a linked employer- is random. This ignores the sorting of worker into firms employee database from Brazil to examine the impact and leads to a bias in estimates of the differential impact of trade reform on the wages of workers employed at of trade on workers at exporting firms relative to non- heterogeneous firms. The analysis of the data at the firm- exporting firms. Using detailed information on worker level confirms earlier findings of a differential positive and firm characteristics to control for compositional effect of trade liberalization on the average wages at effects and using firm-worker match specific effects to exporting firms relative to non-exporting firms. However, account for the endogenous mobility of workers, the this analysis of average firm-level wages is incomplete authors find the differential effect of trade openness on along several dimensions. First, it cannot fully account wages in exporting firms relative to domestic firms to be for the impact of a change in trade barriers on workforce insignificant. Consistent with the models of Helpman, composition especially in terms of unobservable (time- Itskhoki, and Redding (2010) and Davidson, Matusz and invariant) characteristics of workers (innate ability) and Schevchenko (2008), they also find that the workforce any additional productivity that obtains in the context of composition improves systematically in exporting firms employment in the specific firm (match specific ability). in terms of innate (time invariant) worker ability and in Furthermore, the firm-level analysis is undertaken under terms the quality of the worker-firm matches. the assumption that the assignment of workers to firms This paper is a product of the Trade and Integration Team, Development Research Group. It is part of a larger effort by the World Bank to provide open access to its research and make a contribution to development policy discussions around the world. Policy Research Working Papers are also posted on the Web at http://econ.worldbank.org. The author may be contacted at Pravin_Krishna@jhu.edu. The Policy Research Working Paper Series disseminates the findings of work in progress to encourage the exchange of ideas about development issues. An objective of the series is to get the findings out quickly, even if the presentations are less than fully polished. The papers carry the names of the authors and should be cited accordingly. The findings, interpretations, and conclusions expressed in this paper are entirely those of the authors. They do not necessarily represent the views of the International Bank for Reconstruction and Development/World Bank and its affiliated organizations, or those of the Executive Directors of the World Bank or the governments they represent. Produced by the Research Support Team Trade  Liberalization,  Firm  Heterogeneity,  and  Wages:     New  Evidence  from  Matched  Employer–Employee  Data*     Pravin  Krishna   Johns  Hopkins  University  and  NBER     Jennifer  P.  Poole   University  of  California,  Santa  Cruz     Mine  Zeynep  Senses   Johns  Hopkins  University     June  2011   Abstract     In   this   paper,   we   use   a   linked   employer–employee   database   from   Brazil   to   examine   the   impact   of   trade   reform   on   the   wages   of   workers   employed   at   heterogeneous   firms.     Our   analysis   of   the   data   at   the   firm-­‐level  confirms  earlier  findings   of  a  differential  positive  effect   of   trade   liberalization   on   the   average   wages   at   exporting   firms   relative   to   non-­‐exporting   firms.   However,   this   analysis   of   average   firm-­‐level   wages   is   incomplete   along   several   dimensions.   First,   it   cannot   fully   account   for   the   impact   of   a   change   in   trade   barriers   on   workforce  composition  especially  in  terms  of  unobservable  (time-­‐invariant)  characteristics   of   workers   (innate   ability)   and   any   additional   productivity   that   obtains   in   the   context   of   employment   in   the   specific   firm   (match   specific   ability).     Furthermore,   the   firm-­‐level   analysis   is   undertaken   under   the   assumption   that   the   assignment   of   workers   to   firms   is   random.   This   ignores   the   sorting   of   worker   into   firms   and   leads   to   a   bias   in   estimates   of   the   differential   impact   of   trade   on   workers   at   exporting   firms   relative   to   non-­‐exporting   firms.   Using  detailed  information  on  worker  and  firm  characteristics  to  control  for  compositional   effects   and   using   firm-­‐worker   match   specific   effects   to   account   for   the   endogenous   mobility   of   workers,   we   find   the   differential   effect   of   trade   openness   on   wages   in   exporting   firms   relative   to   domestic   firms   to   be   insignificant.   Consistent   with   the   models   of   Helpman,   Itskhoki,  and  Redding  (2010)  and  Davidson,  Matusz  and  Schevchenko  (2008),  we  also  find   that   the   workforce   composition   improves   systematically   in   exporting   firms   in   terms   of   innate  (time  invariant)  worker  ability  and  in  terms  the  quality  of  the  worker-­‐firm  matches.     Keywords:  Trade  liberalization,  firm  heterogeneity,  linked  employer-­‐employee  data.                         JEL  Classification:  F16                                                                                                                 *   Our   special   thanks   to   Paulo   Furtado   de   Castro   for   help   with   the   RAIS   and   SECEX   data,   to   Marc-­‐ Andreas   Muendler   for   sharing   three-­‐firm   random   aggregates   from   the   PIA   data,   and   to   the   Department   of   Economics   and   Academic   Computing   Services   at   the   University   of   California,   San   Diego   for   assistance   with   data   access.   Pravin   Krishna   and   Jennifer   Poole   were   visiting   scholars   in   the   International  Trade  Division  of  the  Development  Research  Group  of  the  World  Bank  while  work  on   this  paper  was  conducted  and  acknowledge  the  funding  support  of  the  World  Bank  executed  Multi-­‐ Donor  Trust  Fund  on  Trade.     1   1.   Introduction     It   is   a   well-­‐established   empirical   regularity   in   the   international   economics   literature   that   even  within  narrowly-­‐defined  industries,  globally-­‐engaged  firms  and  domestic  firms  differ   in   terms   of   their   productivity,   size,   employment   composition,   and   wages   (Bernard   and   Jensen   (1995,   1997)   and   Bernard,   Jensen,   and   Schott   (2009)).1   In   the   presence   of   such   heterogeneity,   trade   liberalization   will   induce   inter-­‐firm   reallocations   within   an   industry   as   the  more  productive,  exporting,  firms  expand  and  the  least  productive  firms  shrink  or  exit   the   industry   (Melitz,   2003).   In   an   environment   with   labor   market   frictions,   this   within-­‐ industry  reallocation  can  have  distributional  consequences  for  workers  employed  in  firms   with  differing  levels  of  global  engagement.       The  international  trade  literature  has  discussed  the  putative  impact  of  trade  liberalization   on  wages  at  different  levels  of  aggregation,  examining  this  question  alternately  at  the  level   of   the   firm   and   at   the   level   of   the   individual   worker.     There   are   various   channels   through   which  a  decline  in  trade  protection  could  result  in  differential  changes  in  average  wages  at   exporting   firms   relative   to   firms   selling   only   to   the   domestic   market.   For   instance,   if   liberalization   is   associated   with   a   change   in   relative   returns   to   worker   characteristics,2   differences   in   work   force   composition   will   imply   that   average   firm-­‐level   wages   in   exporting   firms   will   change   differentially   relative   to   domestic   firms   following   liberalization.   If   trade   liberalization  does  not  affect  the  returns  to  worker  characteristics,  a  differential  wage  effect   may,  nevertheless,  be  observed  if  changes  in  trade  policy  induce  compositional  changes  in   the  workforce  of  exporting  firms  that  are  different  from  those  in  non-­‐exporting  firms.3                                                                                                                     1   Recent   work   extends   the   findings   of   Bernard   and   Jensen   (1995)   using   matched   employer-­‐employee   data   for   Germany   (Schank,   Schnabel,   and   Wagner   (2007)   and   Klein,   Moser,   and   Urban   (2010)),   Denmark   (Munch   and   Skaksen   2008),   and   Mexico   (Frías,   Kaplan,   and   Verhoogen   2009).   See   also   Hummels,  Jorgensen,  Munch  and  Xiang  (2010)  for  analysis  of  the  impact  of  outsourcing  on  wages  and   employment  using  matched  employer-­‐employee  data  from  Denmark.   2   A   vast   empirical   literature   has   examined   the   effects   of   globalization   on   the   wage   outcomes   of   workers   in   the   domestic   economy   with   a   particular   focus   on   the   important   question   of   how   trade   affects   the   average   wages   of   workers   with   different   levels   of   skill.   Classic   papers   in   this   literature   include  Lawrence  and  Slaughter  (1993),  Leamer  (1996),  and  Feenstra  and  Hanson  (1999).  Revenga   (1997),  Currie  and  Harrison  (1997),  and  Trefler  (2004)  analyze  the  effect  of  trade  liberalization  on   firm-­‐level   wages   in   Mexico,   Morocco,   and   Canada,   respectively,   with   mixed   results.   Feenstra   and   Hanson  (2002)  and  Goldberg  and  Pavcnik  (2007)  provide  excellent  survey  treatments.   3  An  expansion  in  exports  could  result  in  differential  labor  quality  upgrading  in  exporting  firms,  for   example,  by  inducing  these  firms  to  adopt  technologies  favoring  highly  skilled  workers,  as  in  Yeaple   (2005)  and  Bustos  (2011),  or  by  inducing  these  firms  to  upgrade  product  and  hence  labor  quality  as   in  Verhoogen  (2008)  and  Kugler  and  Verhoogen  (2008).   2     Furthermore,   in   the   presence   of   labor   market   frictions,   changes   in   trade   protection   may   result   in   differential   changes,   in   exporting   firms   relative   to   non-­‐exporting   firms,   in   the   wages   of   ex-­‐ante   identical   workers.   For   instance,   if   firms   engage   in   some   form   of   rent   sharing   with   their   workers,   the   wages   of   workers   employed   in   exporting   firms,   which   experience   a   relative   improvement   in   their   profits   or   market   share   after   a   decline   in   protection,  will  correspondingly  be  better  compared  to  workers  employed  in  firms  serving   only   the   domestic   market   (Egger   and   Kreickemeier   (2009)   and   Amiti   and   Davis   (forthcoming)).     Equally,   if   the   labor   allocation   process   is   subject   to   search   and   matching   frictions,  exporting  firms  may  screen  (ex-­‐ante  identical)  workers  more  intensively,  employ   workers   of   higher   match-­‐specific-­‐ability,   and   pay   higher   wages   relative   to   non-­‐exporting   firms   as   Helpman,   Itskhoki,   and   Redding   (2010)   have   shown   in   their   comprehensive   theoretical   analysis   of   the   links   between   trade   and   labor   markets   in   this   context.   Here,   opening   the   economy   to   trade   is   predicted   to   alter   this   wage   gap   between   exporting   and   non-­‐exporting  firms  and  to  affect  wage  inequality.4       Does   trade   liberalization,   in   fact,   affect   differently   workers   employed   in   exporting   firms   relative  to  non-­‐exporting  firms?  We  explore  this  issue  empirically  using  a  detailed  dataset   with  matched  employer-­‐employee  data  on  workers  in  Brazil  for  the  years  1990-­‐1998.  The   dataset   traces   individually   identifiable   workers   across   employers   over   time   and   contains   detailed  information  on  worker  characteristics  such  as  age,  gender,  education,  occupation,   and   tenure   at   the   firm   which   allows   us   to   suitably   account   for   the   role   of   unobservable   worker   and   firm   characteristics   in   determining   wages.   We   complement   this   worker-­‐level   information  with  firm-­‐level  data  on  exporter  status  from  the  Brazilian  Customs  Office,  and   industry-­‐level   information   on   trade   protection   levels   to   capture   Brazil’s   main   trade   policy                                                                                                                                                                                                                                                                                                                                               4   More   generally,   the   various   channels   linking   trade   protection   to   wages   that   we   describe   are   each   potentially   associated   with   changes   in   within-­‐group   inequality   (inequality   between   workers   with   identical   observable   characteristics),   in   changes   in   between-­‐group   inequality   (inequality   between   workers  with  different  characteristics,  such  as,  levels  of  education)  and  possibly  even  no  change  in   inequality   at   all.     For   instance,   under   the   rent-­‐sharing   mechanism,   within-­‐group   inequality   will   change   following   trade   liberalization   if   otherwise   identical   workers   are   employed   at   firms   which   experience   differential   profit   changes.   Alternatively,   if   trade   liberalization   changes   the   returns   to   worker   characteristics,   this   will   result   in   a   change   in   between-­‐group   inequality.   Finally,   if   workers   are  paid  competitive  wages  and  the  only  impact  of  trade  liberalization  is  to  reallocate  workers  across   firms  without  any  changes  in  the  returns  to  worker  characteristics,  there  will  be  no  change  in  either   within-­‐group  or  between-­‐group  wage  inequality.   3   reforms.       We   begin   our   analysis   by   exploring   the   behavior   of   average   firm-­‐level   wages   and   find   that  a   decline   in   trade   protection   is   associated   with   an   increase   in   average   wages   in   exporting   firms   relative   to   domestic   firms,   consistent   with   the   findings   of   Amiti   and   Davis   (forthcoming)   for   the   liberalization   period   in   Indonesia5.     However,   we   argue   that   the   analysis   of   average   firm-­‐level   wages,   although   informative,   is   incomplete   along   several   dimensions.   First,   it   cannot   fully   account   for   the   impact   of   a   change   in   trade   barriers   on   workforce   composition   in   terms   of   both   observable   worker   characteristics   (not   available   in   firm-­‐level  datasets),  as  well  as  factors  that  are  observable  to  the  managers  of  the  firm  and   hence   impact   wages   but   are   unobservable   in   the   data,   such   as   the   innate   ability   of   the   worker  and  any  additional  productivity  (ability)  that  obtains  in  the  context  of  employment   in   the   specific   firm   (match   specific   ability).     Furthermore,   the   firm-­‐level   analysis   is   undertaken   under   the   assumption   that   the   assignment   of   workers   to   firms   is   random   and   ignores   the   sorting   of   worker   into   firms   and   the   resulting   change   in   the   distribution   of   match-­‐specific   ability   in   different   firms.   Using   matched   employer-­‐employee   data,   we   test   whether   wage   behavior   at   the   worker   level   confirms   the   maintained   assumption   of   exogenous  worker  mobility,  as  in  Abowd,  McKinney  and  Schmutte  (2010).  Consistent  with   theoretical   models   emphasizing   search   dynamics   or   other   frictions   as   important   determinants  of  the  relationship  between  trade  liberalization  and  wages  such  as  Helpman,   Itskhoki,  and  Redding  (2010)  and  Davidson,  Matusz  and  Schevchenko  (2008),  we  find  that   the  data  decisively  reject  the  assumption  of  exogenous  job  mobility.     Importantly,   using   detailed   information   on   worker   and   firm   characteristics   to   control   for   compositional   effects   and   using   firm-­‐worker   match   specific   effects   to   account   for   the   endogenous  mobility  of  workers,  we  find  the  differential  effect  of  trade  openness  on  wages                                                                                                                   To   our   knowledge   Amiti   and   Davis   (forthcoming)   is   the   first   paper   to   incorporate   firm-­‐level   5   heterogeneity  in  empirically  studying  the  impact  of  trade  liberalization  on  wages.  They  introduce  a   general   equilibrium   model,   which   combines   firm   heterogeneity   in   exporting   patterns,   trade   in   intermediate  inputs,  and  firm-­‐specific  wages.  The  latter  is  incorporated  into  the  model  by  assuming  a   fair-­‐wage   specification   that   results   in   a   direct   link   between   firm   wages   and   firm   profitability.   The   model   predicts   that   a   decline   in   final   goods   tariffs   reduces   the   wages   of   workers   at   firms   that   sell   only  in  the  domestic  market,  but  raises  the  wages  of  workers  at  firms  that  export.  Consistent  with  the   model,   they   find   differential   changes   in   average   firm-­‐level   wages   across   Indonesian   firms   with   different   levels   of   global   engagement   following   liberalization,   which   they   attribute   wholly   to   firm   performance.     4   in   exporting   firms   relative   to   domestic   firms   to   be   insignificant.   Thus,   our   findings   using   matched   employer   employee   data   suggest   a   quite   different   picture   of   the   links   between   trade   liberalization   and   wages   than   is   obtained   by   analyzing   the   data   at   a   more   aggregate   (firm)   level.   Consistent   with   the   models   of   Helpman,   Itskhoki,   and   Redding   (2010)   and   Davidson,   Matusz   and   Schevchenko   (2008),   we   find   that   the   workforce   composition   improves   systematically   in   exporting   firms   in   terms   of   innate   (time   invariant)   ability   and   in   terms   the   quality   of   the   worker-­‐firm   matches.     This   finding   also   serves   to   explain   the   difference   between   the   results   at   the   firm   level   and   those   at   the   worker   level.   If   average   worker  ability  improves  systematically  in  exporting  firms  following  trade  liberalization,  and   this   change   in   not   taken   into   account,   it   will   appear   that   trade   liberalization   leads   to   a   differential   wage   improvement   for   workers   at   exporting   firms   even   when   this   is   not   the   case.       The  remainder  of  this  paper  is  organized  as  follows.  In  Section  2,  we  present  a  background   discussion  on  Brazil’s  trade  policy  reforms  and  describe  the  data.  We  present  the  empirical   methodology  and  estimation  results  for  the  aggregate  (firm-­‐level)  analysis  in  Section  3  and   for  the  analysis  at  the  worker  level  in  Section  4.  Section  5  concludes.       2.   Data  and  Policy  Background     Our   main   data   are   administrative   records   from   Brazil   for   formal-­‐sector   workers   linked   to   their   employers.   We   combine   this   worker-­‐level   information   with   complementary   data   sources   on   firm-­‐level   exporter   status   and   information   on   industry-­‐level   trade   protection   during  Brazil’s  main  trade  policy  reform  period.     2.1.   Brazil’s  Policy  Reforms     The   1990s   were   a   period   of   dramatic   policy   reform   in   Brazil,   providing   a   particularly   appropriate   setting   in   which   to   study   the   impact   of   trade   liberalization   on   wages.   As   compared   to   the   gradual   process   of   globalization   in   many   developed   countries,   Brazil’s   trade   reform   occurred   over   a   relatively   short   period   of   time,   and   with   substantial   cross-­‐ industry   variation.   Furthermore,   many   of   the   policy   reforms   were   arguably   unanticipated   5   and  could  be  viewed  as  exogenous  to  changes  in  wages  at  the  firm  and  worker  level.6       The   second   half   of   the   20th   century   in   Brazil   was   characterized   by   tight   import   substitution   industrialization   policies   designed   to   protect   the   domestic   manufacturing   sector   from   foreign   competition.   Special   import   regimes   and   discretionary   import   controls   like   the   “law   of   similars”,   under   which   goods   were   banned   if   they   too   closely   resembled   a   Brazilian   product,  were  commonplace.  Coverage  of  these  quantitative  restrictions  remained  close  to   100  percent  throughout  this  period,  leaving  Brazilian  manufacturers  highly  protected.       The  1990s,  however,  witnessed  sweeping  changes  in  Brazilian  trade  policy.  Beginning  with   the   Collor   de   Melo   administration   and   continuing   with   President   Cardoso,   Brazil   began   extensive  policies  of  trade  liberalization  in  1988,  which  paved  the  way  for  the  multilateral   free   trade   area,   Mercosul,   with   its   Southern   Cone   neighbors   (Argentina,   Paraguay,   and   Uruguay)   in   1991.   Average   ad   valorem   final   goods   tariff   rates   fell   from   41%   to   18%   between   1988   and   1989.7   The   federal   government   abolished   all   remaining   non-­‐tariff   barriers   inherited   from   the   import   substitution   era   and   brought   nominal   tariffs   further   down   in   1990.   Effective   rates   of   protection   fell   by   over   70%   in   just   four   years—from   approximately   42%,   on   average,   in   1988   to   12%,   on   average,   in   1994   (Kume,   Piani,   and   Souza  2003).         After   decades   of   high   inflation   and   several   unsuccessful   stabilization   attempts,   the   Brazilian   government  succeeded  with  its  macroeconomic  stabilization  plan  (Plano  Real)  in  1994  and   lastingly  ended  hyperinflation.  The  new  currency,  the  real,  began  officially  at  parity  with  the   U.S.   dollar   on   July   1,   1994,   trading   freely   on   international   markets   and   appreciating   in   its   first   months.   In   response,   the   government   partially   reversed   trade   reforms   in   1995   after   manufacturing  industries  lost  competitiveness  due  to  the  real’s  appreciation;8  the  effective   rate  of  protection  climbed  slightly  in  subsequent  years  from  an  average  of  12%  in  1994  to                                                                                                                   6   The   same   argument   could   not   be   made   if   our   analysis   focused   on   industry-­‐level   wages,   given   the   substantial   evidence   for   political   economy   factors   influencing   trade   policy   (see,   for   example,   Grossman  and  Helpman  (1994)  and  Olarreaga  and  Soloaga  (1998)  for  evidence  from  Brazil’s  customs   union,  Mercosul).   7   These   reforms   had   little   impact   on   import   competition   however,   as   non-­‐tariff   barriers   remained   highly  restrictive.   8  Prior  to  1994  and  the  implementation  of  the  new  currency,  controls  on  Brazil’s  former  currency,  the   cruzado,  had  served  as  yet  another  form  of  implicit  import  protection.  In  our  empirical  analysis,  we   allow   for   any   differential   impacts   Brazil’s   exchange   rate   may   have   on   firms   with   differing   trade   exposure.     6   an  average  of  18%  in  1998.9     2.2.   Worker  data     The  linked  employer–employee  data  are  from  the  Brazilian  Labor  Ministry,  which  requires   by   law   that   all   formally-­‐registered   firms   report   to   the   ministry   on   all   workers   in   every   year.10   These   administrative   records   have   been   collected   in   the   Relação   Anual   de   Informações   Sociais   (RAIS)   database   since   1986.   In   this   paper,   we   use   information   from   RAIS   for   the   years   1990   through   1998,   when   we   also   have   complementary   data   on   the   export  status  of  firms  and  industry-­‐level  tariff  rates.       The   main   benefit   of   the   RAIS   database   is   the   ability   to   trace   individually-­‐identifiable   workers   over   time   and   across   firms.   The   data   include   a   unique   worker-­‐identification   number  (which  remains  with  the  worker  throughout  his  work  history),  the  tax  number  of   the  worker’s  firm,  the  industrial  classification  of  the  worker’s  firm11,  and  the  municipality  of   the   worker’s   firm.   These   data   are   particularly   valuable   as   they   offer   variables   beyond   the   available  information  in  many  other  firm-­‐level  databases,  often  used  in  studies  like  ours.  In   particular,   the   data   contain   detailed   information   on   workers’   skill-­‐levels   (as   defined   by   occupation12   and   education),   which   are   paramount   to   this   analysis.   Other   variables   of                                                                                                                   9   Trade   policy   reforms   coincided   with   gradual   foreign   investment   liberalizations   and   the   privatization   of   state-­‐owned   companies,   both   of   which   contributed   to   attracting   substantial   capital   inflows   over   this   time   period.   Meanwhile,   the   government’s   regional   development   plans   also   included  export  promotion  policies  as  explicit  elements,  helping  to  boost  exports  beginning  in  1995.   In   each   specification,   we   include   region-­‐specific   year   dummies   to   capture   the   impact   of   these   and   other  general  macroeconomic  trends  on  wages.   10   The   process   for   firms   to   report   on   their   workers   is   extensive   and   costly.   However,   this   information   is  used  to  administer  payments  of  the  annual  public  wage  supplements  to  every  formally-­‐employed   worker,  thus  creating  a  strong  incentive  for  workers  to  urge  their  employers  to  report  accurately.  In   practice,   however,   only   formally-­‐employed   workers   will   be   properly   recorded.   Goldberg   and   Pavcnik   (2003)   estimate   informal   workers   represent   approximately   16%   of   Brazil’s   manufacturing   labor   force   over   our   sample   period.   The   literature   on   the   impact   of   trade   reform   on   the   informal   sector   offers  mixed  results  (see  Goldberg  and  Pavcnik  (2003),  Menezes-­‐Filho  and  Muendler  (2007),  and  Paz   (2009)).   11  The  sector  classification  used  in  this  paper  comes  from  Brazil’s  statistical  office  (Instituto  Brasileiro   de   Geografia   e   Estatística,   IBGE)   and   is   roughly   comparable   to   a   3-­‐digit   NAICS   classification   (Muendler  2002).   12   Muendler,   Poole,   Ramey   and   Wajnberg   (2004)   map   the   Brazilian   classification   of   occupations   (Classificação   Brasileira   de   Ocupações   (CBO))   to   the   International   Standard   Classification   of   Occupations   (ISCO).   The   CBO   is   a   detailed,   task-­‐oriented   classification   system,   while   ISCO   reflects   a   less-­‐detailed   and   more   skill-­‐oriented   classification   system.   The   skill   classification   is   intended   to   incorporate   on-­‐the-­‐job   experience,   informal   training,   and   the   technological   skill   content   of   the   7   interest  are  the  worker’s  annual  real  wages  in  Brazilian  reais13,  tenure  at  the  firm  in  months,   gender,  and  age.       We  restrict  observations  as  follows.  First,  we  draw  a  one  percent  random  sample  from  the   complete   list   of   workers   ever   to   appear   in   the   national   records.   We   match   the   sampled   workers   back   to   the   population   data   to   find   all   firms   in   which   these   workers   were   ever   employed   over   time   to   create   a   complete   employment   history   of   this   one   percent   random   sample   of   the   population   of   the   Brazilian   formal-­‐sector   labor   force.14   Next,   we   keep   only   workers  with  valid  worker  identification  numbers  to  ensure  that  we  can  track  individuals   over  time.  As  is  standard  in  the  literature,  we  include  only  prime-­‐age  workers  between  the   ages   of   15   and   64   years,   workers   with   a   positive   average   monthly   wage,   and   workers   in   private-­‐sector   jobs.   Finally,   for   workers   with   multiple   jobs   in   a   given   year,   only   the   most   recent  job  is  included  in  the  sample.  If  a  worker  has  multiple  current  jobs,  only  the  highest   paying  job  is  included.     2.3.   Complementary  data     Export  Status   Brazilian   firms’   tax   identification   numbers   are   common   across   many   databases,   allowing   us   to   match   the   RAIS   data   to   complementary   firm-­‐level   data   sources.   Information   on   firm-­‐level   export   transactions   is   available   from   the   Brazilian   Customs   Office   (Secretaria  de  Comércio  Exterior,  SECEX).  SECEX  records  all  legally-­‐registered  firms  in  Brazil   with  at  least  one  export  transaction  in  a  given  year.  We  match  the  SECEX  firm-­‐level  exporter   status   data   to   our   RAIS   worker   data   by   the   firm’s   tax   identification   code   to   identify   workers   at   exporting   and   non-­‐exporting   firms.   We   define   an   indicator   variable   equal   to   one   if   a   worker  holds  a  job  at  a  firm  with  a  positive  dollar  value  of  free-­‐on-­‐board  exports  in  a  given   year  and  zero  otherwise.                                                                                                                                                                                                                                                                                                                                                   occupation   (Elias   and   Birch   1994).   ISCO   occupations   can   be   grouped   into   four   broad   occupational   categories  following  Abowd,  Kramarz,  Margolis,  and  Troske  (2001)  to  reflect  the  skill-­‐intensity  of  the   occupation.   13   RAIS   reports   an   average   monthly   wage   (in   multiples   of   the   current   minimum   wage)   for   each   job   in   which  a  worker  is  employed  in  each  year.  In  combination  with  information  on  the  number  of  months   a  worker  was  employed  during  the  year  and  deflated  minimum  wage  information  in  reais  from  the   Brazilian  Central  Bank,  we  calculate  an  annual  real  wage  for  each  worker.   14   Note   that   any   firm-­‐level   aggregates   we   use   in   our   analysis,   however,   are   based   on   the   complete   population  of  workers.   8   As   would   be   predicted   by   new   heterogeneous   firm   models   of   international   trade,   Brazil’s   trade  liberalization  in  the  early  1990s  was  associated  with  significant  firm-­‐level  entry  into   exporting.   The   share   of   exporting   firms   increased   over   50%—from   only   8.5%   in   1990   to   12.9%  in  1994  before  leveling  off.     Tariffs   In  our  analysis  of  Brazil’s  trade  policy,  we  concentrate  on  two  trade  protection   measures:   the   final   goods   output   tariff   and   the   effective   rate   of   protection   (ERP).   The   effective  rate  of  protection  allows  us  to  incorporate  changes  in  tariffs  placed  on  inputs  into  a   firm’s   production   process.   Our   data   on   final   goods   tariffs   are   from   Muendler   (2003),   who   reports   monthly   nominal   final   goods   output   tariffs   at   the   Nível   80   Brazilian   industrial   classification   level.   We   access   monthly   ERP   at   the   Nível   80   industrial   classification   level   from  Kume,  Piani,  and  Souza  (2003).15  We  match  the  December  tariffs  from  1990  to  1998   with  our  annual  RAIS  worker  data  by  the  2-­‐digit  IBGE  subsector16  to  identify  workers  and   firms  in  industries  with  differential  rates  of  protection  and  liberalization  experiences.         Figure   2.1   displays   both   the   mean   and   median   values   of   the   effective   rate   of   protection   in   the   manufacturing   sector   during   the   1990   to   1998   period.   The   early   1990s   experienced   sharp   declines   in   the   effective   rate   of   protection.   Mean   rates   fell   from   approximately   60   percent   to   20   percent,   while   median   rates   fell   from   40   percent   to   20   percent   in   a   half-­‐ decade.  The  slight  aforementioned  protectionist  response  to  the  appreciation  of  the  real  is   also   evident.   Most   strongly   in   the   early   part   of   the   decade,   median   ERP   was   smaller   than   average   ERP,   suggesting   that   the   distribution   of   the   effective   rate   of   protection   is   skewed   to   the   right.   Over   time,   as   the   sectoral   variation   narrows,   the   mean   ERP   and   median   ERP   converge.         This   substantial   cross-­‐industry   variation   in   both   levels   and   changes   in   the   ERP   is                                                                                                                   15   Kume,   Piani,   and   Souza   (2003)   formally   measure   ERP   for   sector   k   as   the   increase   in   the   value-­‐ added  due  to  the  structure  of  tariffs  relative  to  value-­‐added  at  free  trade  prices,  as  follows:   ERPk = τ k − ∑a τ mk k d ,   where   a = amk (1 + τ k )   is   the   input-­‐output   matrix   at   free-­‐trade   1 − ∑a mk mk 1 + τm international  prices,   a  is  the  input-­‐output  matrix  at  distorted  domestic  prices,  and   τ  and   τ  are  the   d mk k m final  goods  and  intermediate  inputs  tariffs,  respectively.   16   We   follow   industry   concordances   available   at   http://econ.ucsd.edu/muendler/brazil   to   concord   the   € € € € € Nível   80   classification   to   the   2-­‐digit   IBGE   subsector   classification   used   in   RAIS.   This   constitutes   the   IBGE  subsectors  2  through  13.   9   documented  in  more  detail  in  Figure  2.2  where  we  present  the  distribution  of  tariffs  across   industries  in  1990  and  1998,  and  the  average  annual  change  in  ERP  during  this  period.  Note   that  compared  to  1990,  the  distribution  of  the  effective  rate  of  protection  across  industries   at   the   end   of   our   sample   is   much   more   compressed   around   a   lower   mean.   We   also   note   substantial  variation  across  sectors  in  the  average  annual  changes  in  protection  rates.       2.4.   Descriptive  statistics     The   complete   matched   data   include   3,932,297   worker-­‐firm-­‐year   observations,   with   657,572  workers  in  490,884  firms.  Our  final  sample  of  the  manufacturing  sector,  however,   has   504,660   worker-­‐firm-­‐year   observations,   with   114,042   workers   in   58,578   firms.   We   report   detailed   descriptive   statistics   in   Table   2.1.   Roughly   three-­‐quarters   of   the   formal-­‐ sector   labor   force   have   at   most   a   primary   school   education.   An   additional   18%   of   manufacturing   sector   workers   are   high   school   educated,   and   only   7%   of   workers   have   a   college   degree.   The   majority   of   Brazil’s   labor   force   is   employed   in   skilled   blue-­‐collar   occupations,   like   machine   operators   and   assemblers.   Almost   20%   of   the   manufacturing   workforce  is  in  professional  or  managerial  positions,  with  11%  in  unskilled  blue-­‐collar  jobs.   Other   white-­‐collar   workers   (for   example,   those   in   secretarial   and   office   assistant   occupations)  represent  only  8%  of  the  formal  sector  manufacturing  labor  force.  The  average   number  of  employees  in  manufacturing  firms  is  relatively  small  at  73.     There   are   64,212   workers   working   in   11,143   exporting   firms,   and   80,895   workers   working   in   53,537   domestic   firms   over   the   sample   period.   Exporters   pay   a   substantially   higher   average   wage   than   do   non-­‐exporters.   Exporters   employ   a   higher   share   of   skilled   workers,   on  average,  compared  to  non-­‐exporting  firms,  consistent  with  the  existing  literature.  Almost   10%  of  workers  at  exporting  firms  are  college  educated  and  21%  are  high-­‐school  graduates.   In   comparison,   in   non-­‐exporting   firms   the   share   of   college   educated   and   high-­‐school   educated  workers  are  4%  and  17%,  respectively.17  Exporters  also  employ  a  higher  share  of   workers  in  professional,  managerial,  and  technical  occupations.  Exporters  are  significantly   larger   in   terms   of   their   average   employment   compared   to   non-­‐exporters.   The   average   exporter   employs   346   employees,   while   the   average   non-­‐exporter   has   only   37   employees.                                                                                                                   17   Note   that   in   a   country   like   Brazil,   the   share   of   workers   with   a   high-­‐school   education   is   a   more   meaningful  representation  of  skill  (Gonzaga,  Menezes-­‐Filho,  and  Terra  2006).   10   The  set  of  firm  level  variables  available  in  our  dataset  allow  us  to  appropriately  control  for   these   differences   between   exporters   and   domestic   firms   in   identifying   the   heterogeneous   impact  of  trade  policy  on  wages  of  these  firms.       3.  Firm-­‐Level  Analysis     We  begin  our  analysis  at  the  firm  level  to  ensure  the  comparability  of  our  results  with  those   of   the   existing   literature   based   on   firm-­‐level   data   and   to   highlight   the   importance   of   introducing   worker   and   match   heterogeneity   into   the   analysis.   To   this   end,   we   aggregate   the   matched   employer-­‐employee   data   to   the   firm   level   and   estimate   the   following   specification:     ln y jt = γ 1t kt + γ 2 t kt * Exp jt + γ 3 RERt * Exp jt + γ 4 Exp jt + Ψ j + δ tr + βZ jt + ε jt                                                                (1)     € where  the  dependent  variable,   !"# ! "# $ ,  is  the  logarithm  of  average  wages  at  the  firm  level   for  firm  j  at  time  t.   ! "!  denotes  the  level  of  protection  in  sector  k  in  which  the  firm  operates,   and   !"# $%   is   an   indicator   variable   equal   to   one   if   firm   j   reports   a   positive   dollar   value   of   exports   at   time   t   and   zero   otherwise.   The   level   of   protection   at   the   sector-­‐level   is   measured   by  both  tariffs  and  the  effective  rate  of  protection  (ERP).  We  use  the  latter  measure  in  our   main  specifications,  since  in  an  environment  in  which  Brazilian  firms  face  declines  in  both   final   goods   and   intermediate   input   tariffs,   the   ERP   is   a   more   appropriate   measure   of   protection   faced   by   domestic   firms.   In   each   specification,   we   include   an   interaction   term   between   ! "!   and   !"# $%   to   allow   for   changes   in   protection   to   have   differential   effects   on   exporters  and  firms  serving  only  the  domestic  market.     As   we   noted   earlier,   the   post-­‐liberalization   period   in   Brazil   coincided   with   a   period   of   an   appreciation   of   the   currency,   the   real,   making   Brazilian   goods   less   competitive   on   international   markets,   while   making   imported   goods   cheaper   in   real   terms.   Failing   to   incorporate   such   fluctuations   in   exchange   rates   into   our   analysis   could   bias   the   estimated   effect   of   liberalization   on   wages.   Henceforth,   in   each   specification,   we   also   include   an   11   interaction  of  Brazil’s  real  exchange  rate  (RER)18  and  the  firm’s  export  status.19       The   time-­‐varying,   firm-­‐level   controls,   ! "# ,   include   variables   available   in   standard   firm-­‐level   data   sets   such   as   log   employment,   and   the   occupational   skill   composition20   of   the   firm   in   addition   to   average   worker   tenure   at   the   firm,   and   controls   for   the   age21,   gender,   and   educational   skill   composition22   of   the   firm.23   Each   specification   also   includes   firm   fixed   effects,   ! ! ,   accounting   for   time-­‐invariant,   firm   characteristics   and   interactive   region-­‐year   fixed   effects,   !!" ,   capturing   the   average   effect   of   policy   changes   that   may   differentially   impact   wages   of   firms   in   different   regions   of   Brazil.24   Here,   ! !"   is   an   error   term   that   is   assumed   to   exhibit   no   serial   correlation,   and   to   be   orthogonal   to   all   regressors.   In   each   specification,  the  standard  errors  are  clustered  at  the  industry-­‐year  level  to  account  for  the   possibility  of  within-­‐industry,  across-­‐firm  correlation  in  errors  following  Moulton  (1990).     In  interpreting  our  estimates  from  specification  (1)  we  focus  specifically  on  the  magnitude   of   the   differential   change   in   average   firm-­‐level   wages   at   exporters   relative   to   non-­‐exporters   ( ! ! )   as   well   as   the   overall   wage   impact   of   a   decline   in   protection   for   exporters   ( ! ! + ! " )   and   non-­‐exporters  ( !! ),  separately.  The  responsiveness  of  average  wages  in  firms  serving  only                                                                                                                   18   The   real   exchange   rate   series   for   Brazil   is   constructed   in   Muendler   (2003)   and   is   available   at   http://www.econ.ucsd.edu/muendler/html/brazil.html#brazdata.   19   Since   the   overall   impact   of   the   time-­‐varying,   economy-­‐wide   RER   is   absorbed   by   the   region-­‐specific   year   effects   ( δ tr ),   we   can   only   separately   identify   the   effect   of   the   RER   changes   on   exporting   firms   relative  to  domestic  firms.  We  also  conduct  robustness  checks  using  industry-­‐specific  exchange  rates.   20   We   define   the   firm’s   occupational   skill   composition   as   the   share   of   the   firm’s   workforce   in   four   occupational  categories:    unskilled  blue  collar,  skilled  blue  collar,  other  white  collar,  and  professional   € and  managerial  workers.  Unskilled  blue-­‐collar  workers  are  the  omitted  category.   21   We   define   the   firm’s   age   composition   as   the   share   of   the   firm’s   workforce   in   six   age   categories:     youth  (15-­‐17),  adolescent  (18-­‐24),  nascent  career  (25-­‐29),  early  career  (30-­‐39),  peak  career  (40-­‐49),   and  late  career  (50-­‐64).  Youth  workers  are  the  omitted  category.       22   We   define   the   firm’s   educational   skill   composition   as   the   share   of   the   firm   in   three   education   categories:   less   than   high   school,   at   least   high   school,   and   more   than   high   school.   Less   than   high   school  is  the  omitted  category.       23  By  including  both  the  educational  and  the  occupational  skill  composition  of  the  firm,  we  are  able  to   allow   for   the   possibility   that   firms   use   increasingly   higher-­‐skilled   individuals   (as   defined   by   education)  in  lower-­‐skilled  occupations.  See  Muendler  (2008)  for  evidence  on  the  skill  upgrading  of   occupations  in  response  to  trade  reform  in  Brazil.   24  We  consider  Brazil’s  five  main  geographic  regions:  the  North,  Northeast,  Center-­‐West,  Southeast,   and  South.   12   the   domestic   market   to   changes   in   protection   is   reflected   in   the   coefficient   !! .   A   positive   !!   would  suggest  that  a  decline  in  protection  is  associated  with  a  decrease  in  average  wages  in   firms  serving  solely  the  domestic  market.  Note  that  when  ERP  is  the  measure  of  protection   (instead  of  tariffs),   !!   would  reflect  a  combined  effect  of  the  positive  impact  of  a  reduction   in  input  tariffs  through  prices  and  access  to  enhanced  variety  and  quality  on  firm  profits25,   as  well  as  any  negative  impact  of  increased  import  competition  due  to  a  decline  in  output   tariffs.   Hence,   we   expect   the   coefficient   to   be   smaller   in   magnitude   when   the   measure   of   protection   is   ERP   compared   to   the   estimated   coefficient   when   protection   is   measured   by   (output)  tariffs.       The   coefficient   on   the   interaction   term,   ! ! ,   reflects   the   differential   effect   of   trade   policy   changes   on   average   wages   in   exporting   firms   relative   to   firms   serving   only   the   domestic   market.   If   a   decline   in   protection   results   in   a   differential   increase   in   firm-­‐level   average   wages   in   exporting   firms,   we   expect   ! ! < " .   There   are   various   reasons   a   decline   in   protection   could   result   in   a   differential   increase   in   firm-­‐level   average   wages   of   exporting   firms.   For   example,   if   firms   engage   in   some   form   of   rent-­‐sharing   with   their   workers,   workers  employed  in  exporting  firms,  whose  prospects  improve  as  a  result  of  a  decline  in   protection,   could   experience   an   increase   in   their   wages.   Similarly,   if   liberalization   is   associated  with  a  change  in  the  relative  returns  to  skill,  and  if  exporting  firms  differ  in  terms   of   their   labor   force   composition,   average   firm-­‐level   wages   in   exporting   firms   will   increase   relative   to   domestic   firms.   Also,   the   relative   increase   in   wages   in   exporting   firms   could   be   a   reflection  of  a  change  on  workforce  composition  in  terms  of  factors  that  are  observable  to   the  managers  of  the  firm  and  hence  impact  wages,  but  are  unobservable  in  the  data  (such  as   innate  worker  ability  or  match-­‐specific  ability).         3.1  Estimation  Results                                                                                                                     25   See   Arkolakis,   Demidova,   Klenow,   and   Rodriguez-­‐Clare   (2008)   and   Goldberg,   Khandelwal,   Pavcnik,   and   Topalova   (2008)   for   evidence   on   improved   input   variety,   and   Kugler   and   Verhoogen   (2008),   Amiti   and   Konings   (2007),   Csillag   and   Koren   (2009),   and   Halpern,   Koren   and   Szeidl   (2009)   for   evidence  on  improved  input  quality.     13   Estimation   results   from   equation   (1)   with   tariffs26   as   the   measure   of   protection   are   reported  in  Table  3.1.  The  results  suggest  that  a  decline  in  tariffs  is  associated  with  a  decline   in  average  wages  at  non-­‐exporting  firms,  consistent  with  a  negative  impact  of  an  increase  in   foreign  competition  on  these  firms.  We  find  that  a  ten  percentage  point  decrease  in  tariffs   leads  to  a  decrease  in  average  firm-­‐level  wages  by  1.7%  for  these  firms.  The  negative  and   significant   coefficient   on   the   interaction   term   between   tariffs   and   export   status   suggests   that  the  wages  in  exporting  firms  increase  in  response  to  a  decline  in  tariffs  relative  to  firms   serving  only  the  domestic  market.  We  find  that  a  change  in  tariffs  has  no  statistical  impact   on  average  wages  at  the  firm-­‐level  for  exporting  firms.27  The  RER-­‐exporter  interaction  term   suggests  that  a  depreciation  in  the  RER  (a  decrease  in  the  RER  as  is  it  defined  in  our  data)   increases  the  wages  in  exporting  firms  relative  to  non-­‐exporting  firms,  as  expected.  All  the   firm-­‐level   controls   are   statistically   significant   and   enter   with   the   expected   signs   and   magnitudes.   Average   firm-­‐level   wages   are   increasing   with   the   average   tenure   and   age-­‐ profile  at  the  firm,  while  they  are  decreasing  in  the  share  of  female  workers  employed  at  the   firm.  Wages  are  increasing  in  both  the  educational  and  occupational  skill  composition  of  the   firm  and  the  size  if  the  firm.       Next,   we   test   whether   the   differential   impact   of   tariffs   we   document   on   exporting   firms  holds  equally  for  firms  operating  in  all  industries.  More  specifically,  we  allow  for  the   effect   of   a   change   in   tariffs   to   be   different   for   firms   operating   in   Brazil’s   comparative   advantage   sectors.   We   expect   that   following   liberalization,   exporters   in   these   sectors   will   experience   a   more   pronounced   increase   in   profitability   relative   to   exporters   in   low   comparative   advantage   sectors   and   hence,   expect   a   stronger   impact   on   average   wages   at   these  firms.  We  divide  our  sample  into  high  and  low  comparative  advantage  sectors  using   data  on  each  industry’s  Balassa  (1965)  comparative  advantage.28  The  next  two  columns  in   Table  3.1  report  our  results  by  the  comparative  advantage  of  the  firm’s  sector  where   high   (low)  comparative  advantage  sectors  are  those  with  an  above  (below)  median  value  of  the                                                                                                                   26  Our  estimation  results  are  essentially   the  same  when  we  use  tariffs  weighted  by  the  value  added  of   the  industry  instead  of  un-­‐weighted  tariffs.   27   The   absolute   effect   on   exporters,   the   F-­‐statistic   and   corresponding   p-­‐value   on   the   joint   significance   of  the  coefficients  are  reported  at  the  bottom  of  Table  3.1.   28  Industry  k’s  Balassa  (1965)  comparative  advantage  in  year  t  is  constructed  in  Muendler  (2007)  as   follows:       Comp_Advk,t  =     Brazil X k,t / m Brazil X m,t where  Xkt  are  exports.     ∑ World X k,t / World X m,t ∑ m 14   € Balassa   (1965)   comparative   advantage   measure   across   all   merchandise   trade   sectors   in   1986.29   30  Interestingly,  we  find  the  differential  impact  of  trade  liberalization  on  exporters   to  be  prevalent  only  for  firms  operating  in  high  comparative  advantage  sectors.  Firms  in  low   comparative   advantage   sectors   experience   a   decline   in   average   wages   regardless   of   their   export  status.     During   the   liberalization   period,   Brazilian   firms   faced   declines   in   both   final   goods   and   in   intermediate   input   tariffs.   While   a   decrease   in   final   goods   tariffs   could   decrease   the   profitability   of   domestic   firms   by   increasing   the   foreign   competition   that   they   face,   a   decrease   in   input   tariffs   is   likely   to   have   the   opposite   effect   by   decreasing   the   price   of   inputs,  and  improving  the  variety  and  possibly  quality  of  inputs  that  the  firm  has  access  to.   If  the  industries  that  experienced  a  decline  in  final  goods  tariffs  also  experienced  a  decline   in  input  tariffs,  the  product  tariff  is  likely  to  overestimate  the  actual  decrease  in  protection   that   the   industry   has   experienced.   To   address   this   issue,   we   repeat   the   previous   analysis   with   the   effective   rate   of   protection   (ERP)   instead   of   (output)   tariffs   as   the   measure   of   protection.   The  estimation  results  suggest  that  a  decline  in  ERP  has  no  significant  impact  on   average   wages   at   non-­‐exporting   firms.   Improved   access   to   imported   intermediates   from   abroad  could  explain  the  difference  between  these  results  and  those  reported  in  first  half  of   Table  3.1.  Note  that  this  coefficient  now  reflects  a  combined  effect  of  the  positive  impact  of  a   reduction   in   input   tariffs   through   prices   and   access   to   variety   and   quality,   as   well   as   any   negative   impact   of   increased   import   competition   due   to   a   decline   in   output   tariffs.   The   negative   and   significant   coefficient   on   the   interaction   term   suggests   that   the   wages   in   exporting   firms   increase   in   response   to   a   decline   in   the   ERP.     A   ten   percentage   point   decrease   in   the   ERP   increases   average   wages   by   1%   at   exporting   firms.   Similar   to   the   results   for   output   tariffs,   in   the   high   comparative   advantage   sector,   we   find   that   a   decline   in   ERP   is   associated   with   a   differential   increase   in   wages   in   exporting   firms   relative   to   their   non-­‐exporting  counterparts.  The  increase  in  wages  associated  with  a  ten  percentage  point                                                                                                                   29   We   choose   the   pre-­‐reform   year   of   1986   to   avoid   any   possible   endogeneity   between   the   comparative  advantage  measure  based  on  exports  and  tariff  reforms  which  began  in  1988.  We  also   experimented   with   generating   the   comparative   advantage   measure   across   only   manufacturing   sectors   and   using   a   post-­‐reform   year   with   no   difference   in   the   results.   Brazil’s   Balassa   (1965)   revealed  comparative  advantage  is  largely  time-­‐invariant.   30   The   following   sectors   are   defined   as   high   comparative   advantage   sectors:     Manufacture   of   non-­‐ metallic   mineral   products,   Manufacture   of   metallic   products,   Manufacture   of   transport   equipment,   Manufacture   of   wood   products   and   furniture,   Manufacture   of   footwear,   and   the   Manufacture   of   food,   beverages,  and  ethyl  alcohol.   15   decrease  in  ERP  is  2.9%  for  exporters  while  it  is  0.8%  (and  significant  only  at  10%  level)  for   firms  serving  the  domestic  market.  The  impact  of  trade  liberalization  on  average  firm  wages   is  not  statistically  significant  for  domestic  firms  or  exporters  in  low  comparative  advantage   sectors.  Our  results  also  indicate  that  the  exporter  premium  is  slightly  higher  for  exporters   in  the  high  comparative  advantage  sector.     A  potential  concern  for  the  results  reported  in  Table  3.1  is  the  selection  bias  introduced  by   the   heterogeneity   of   firms   exiting   the   sample   following   trade   liberalization.   If   a   decline   in   ERP   results   in   the   exit   of   low   productivity   firms,   the   negative   effect   of   liberalization   on   domestic   firms   will   be   underestimated,   as   the   remaining   firms   in   the   sample   would   have   high   productivity   and   pay   high   wages.   To   evaluate   the   relevance   of   this   possibility   in   explaining  the  differential  impact  we  find  on  exporting  firms,  we  repeat  our  analysis  for  a   balanced   panel   of   firms,   which   were   under   operation   during   the   entire   sample   period.   Results  reported  in  the  first  column  of  Table  3.2  suggest  that  restricting  our  sample  to  those   firms,   which   do   not   enter   or   exit,   does   not   alter   the   magnitude   or   the   significance   of   our   main  coefficient  of  interest,  suggesting  that  our  results  are  not  driven  by  sample-­‐selection.31       We  provide  further  robustness  checks  in  the  remaining  columns  of  Table  3.2.  As  we  address   in   the   data   section,   our   main   firm-­‐level   regressions   draw   on   the   complete   employment   history   of   a   1%   random   sample   of   the   population   of   Brazil’s   formal-­‐sector   labor   force.   To   ensure   this   data   is   representative   of   Brazilian   firms   and   industries,   in   the   second   column   of   Table   3.2,   we   repeat   the   analysis   drawing   on   the   complete   employment   history   of   a   5%   random   sample   of   formal-­‐sector   males   living   in   metropolitan   areas.   In   the   third   column,   we   restrict  the  data  to  Brazil’s  main  trade  reform  period  (1990-­‐1994)  when  average  protection   levels   consistently   declined.   In   both   cases,   our   main   coefficient   of   interest   remains   significant   with   little   change   in   its   magnitude.   The   results   reported   in   the   next   column   suggest   that   our   findings   are   robust   to   replacing   the   economy-­‐wide   real   exchange   rate   with   industry-­‐specific   real   exchange   rates   in   order   to   capture   differences   in   the   relative                                                                                                                   31   Similarly,   if   the   least   productive   exporters   switch   out   of   exporting   following   liberalization,   the   magnitude   of   the   differential   effect   of   a   decline   in   ERP   on   exporters   will   be   biased   upwards.   In   unreported  regressions,  available  by  request,  we  include  log  total  factor  productivity  as  an  additional   explanatory   variable   based   on   estimates   from   Muendler   (2004).   We   find   the   effect   of   log   TFP   on   average  firm  wages  to  be  insignificant.  Importantly,  the  inclusion  of  log  TFP  does  not  alter  the  main   coefficient  of  interest.     16   importance  of  trading  partners  across  industries.32       We  also  test  whether  our  results  are  sensitive  to  the  exporting  thresholds  we  use  to  assign   the  indicator  variable  denoting  a  firm’s  export  status.  In  the  main  firm-­‐level  specifications,  a   firm   is   defined   as   an   exporter   if   it   exported   any   positive   dollar   amount   that   year.   Instead,   in   columns  4  and  5,  we  only  consider  firms  with  an  export  value  more  than  the  5th  percentile   (cutoff   5)   in   that   year,   and   more   than   the   10th   percentile   (cutoff   10)   as   exporting   firms,   respectively.   Next,   we   replace   the   exporter   status   dummy   in   our   main   specification   with   two  time-­‐invariant  measures  of  export  status.  Export90  takes  the  value  1  if  the  firm  was  an   exporter  as  of  the  beginning  of  our  sample,  and  zero  otherwise.  Export_Once  takes  value  1  if   the   firm   exported   for   at   least   one   year   during   the   sample   period.   Our   estimation   results   continue   to   suggest   a   differential   positive   impact   of   liberalization   on   wages   at   exporting   firms  relative  to   non-­‐exporters.   In   the   last   column,   we   report   results   from   a   specification   in   which  we  include  the  logarithm  of  the  value  of  exports  for  firms  with  positive  exports.  Our   results   indicate   that   conditional   on   exporting,   there   is   a   differential   increase   in   wages   at   firms  with  higher  values  of  exports  following  liberalization.         Next,   we   test   whether   the   differential   impact   on   exporters   we   document   could   simply   be   attributed   to   compositional   differences   between   exporters   and   non-­‐exporters   in   an   environment   in   which   the   returns   to   observable   worker   characteristics   are   changing   as   a   result   of   liberalization.   Specifically,   we   allow   for   changes   in   the   premium   paid   by   firms   with   different   workforce   skill   compositions,   by   interacting   ERP   with   measures   of   labor   force   composition  at  the  firm  level  in  equation  (1)  and  find  no  impact  on  our  main  coefficient  of   interest.  This  finding  suggests  that  the  differential  effect  that  we  find  cannot  be  explained  by   changes  in  the  relative  returns  to  observable  characteristics  following  liberalization.33     Finally,   we   consider   the   possibility   that   an   omission   of   the   importer   status   of   the   firm   could                                                                                                                   32  We  construct  industry-­‐specific  real  exchange  rates  using  time-­‐varying  trade  weights,  as  in   Goldberg  (2004).  More  specifically,  we  calculate   ⎛ ⎛ ⎞ ⎞ ⎜ ⎜ X tkc M tkc k ⎟ c ⎟ RER _ ind = ∑ ⎜ ⎜ .5 + .5 t ⎟ RERt ⎟  where   RER  are  the  bilateral  exchange   c ∑ X tkc ∑ M tkc t c ⎜ ⎜ ⎟ ⎟ ⎝ ⎝ c c ⎠ € ⎠ rates  for  trading  partner  c  of  Brazil,   X t kc  and   M t kc  are  exports  and  imports  in  industry  k  to  or  from   country  c  at  time  t.  Note  that   RER is  also  included  in  this  specification.   c t 33  These  results  are  not  reported  to  conserve  space  and  are  available  upon  request.   € 17   bias   our   results   if   improved   access   to   foreign   intermediate   inputs   increases   wages   at   the   firm  level  and  if  the  firm’s  export  status  is  correlated  with  its  import  status.  Amiti  and  Davis   (forthcoming)   find   this   effect   to   be   important   in   Indonesia:   following   a   decline   in   input   tariffs,  average  wages  in  importing  firms  increase  relative  to  firms  that  do  not  import.  Our   estimation   results   based   on   a   sub-­‐sample   of   firms   for   which   data   on   import   status   is   available   suggest   no   such   differential   impact   on   importing   firms   in   Brazil.   Moreover,   the   differential  impact  of  liberalization  on  average  wages  in  exporting  firms  is  robust  to  various   specifications   controlling   for   the   import   status   of   the   firms.   Appendix   includes   a   more   detailed  description  of  these  results.     3.2  Discussion  of  Firm-­‐Level  Analysis       Our   firm-­‐level   analysis   confirms   findings   in   earlier   studies   regarding   the   differential   impact   of   trade   reform   on   average   wages   at   firms   with   differing   degrees   of   trade   exposure,   especially   in   high   comparative   advantage   sectors.   However,   this   analysis   of   average   firm-­‐ level   wages,   although   informative,   is   not   well   suited   to   examine   the   differential   impact   of   liberalization  on  workers  in  heterogeneous  firms  for  a  number  of  inter-­‐related  reasons.  In   general,  we  would  expect  that  in  addition  to  observable  worker  and  firm  characteristics,  the   allocation   of   workers   to   firms   is   a   function   of   the   worker   characteristics   that   are   unobservable   in   the   but   the   managers   can   observe   and   reward,   such   as   the   innate   (time-­‐ invariant)  ability  of  the  worker  and  any  additional  productivity  (ability)  that  obtains  in  the   context   of   employment   in   the   specific   firm   (match-­‐specific   ability).     Recent   theoretical   models  (including  Mortensen  (2003),  Postel-­‐Vinay  and  Robin  (2002),  Lentz  (2010),  Shimer   (2005))   and   Gibbons   et   al.   (2005))   variously   describe   the   central   role   played   by   ex-­‐ante   unobservable   worker   characteristics   in   determining   the   equilibrium   assignment   of   workers   to   firms.   In   the   context   of   international   trade   and   labor   markets,   Helpman,   Itskhoki,   and   Redding   (2010),   who   model   the   labor   allocation   process   with   heterogeneous   firms   as   being   subject  to  search  and  matching  frictions,  find  that  the  more  productive,  exporting,  firms  will   screen   workers   more   intensively   and   employ   workers   of   higher   match-­‐specific   ability,   i.e.,   the   equilibrium   assignment   of   workers   is   again   a   function   of   unobservable   match   specific   worker  ability  and  is  thus  non-­‐random.       Importantly,  in  an  environment  in  which  firms  are  changing  the  composition  and  quality  of   18   their  labor  force  in  response  to  liberalization,34  analysis  conducted  at  the  firm  level  faces  at   least   two   problems.   If   exporting   firms   respond   to   liberalization   by   changing   the   composition  of  their  workforce  systematically,  (for  example,  towards  workers  with  higher   innate  ability  or  match-­‐specific  ability)  our  estimates  will  be  biased.  This  is  because  part  of   the  differential  effect  we  find  for  exporters  at  the  firm-­‐level  could  be  due  to  compositional   differences   between   firms   with   different   trade   orientation   and   not   because   otherwise   identical  workers  are  being  paid  different  wages  in  different  firms.  Furthermore,  when  the   job  mobility  of  workers  is  at  least  partly  determined  by  their  unobservable  characteristics   (endogenous   mobility),   estimates   of   the   parameters   in   (1)   will   be   biased.   This   is   because   non-­‐random   job   assignment   implies   a   correlation   between   the   error   term   ε jt (which     subsumes   the   un-­‐observables   associated   with   workers   in   firm   j   at   time   t)   and   the   firm’s   characteristics  represented  by  the  right  hand  side  variables, Ψ j  and   Z jt ,  and  thus  a  failure   of  the  maintained  assumption, E (ε jt | Ψ j , Z jt ) = 0 ,  underlying  the  estimation.         In  the  following  section,  we  describe  the  worker-­‐level  analysis  we  undertake  using  matched   employer-­‐employee   data   to   account   for   the   issues   of   unobservable   worker   ability   differences   and   endogenous   job   mobility   that   we   have   just   described.   We   also   describe   in   much  greater  detail  the  issue  of  endogenous  job  mobility  which  persists,  in  principle,  with   worker-­‐level   analysis,   but   can   be   dealt   with   using   firm-­‐worker   match   effects   in   the   wage   specification.         4.      Worker-­‐Level  Analysis     We   begin   our   worker-­‐level   analysis   by   considering   the   basic   specification   of   Abowd,   Kramarz,  and  Margolis  (1999)  in  which  a  worker’s  wages  can  be  decomposed  as  follows:                                                                                                                     34  In   unreported   results   available   upon   request,   we   provide   some   evidence   of   differential   skill   upgrading  at  exporting  firms  relative  to  non-­‐exporting  firms  with  trade  liberalization.  Specifically,  we   re-­‐estimate   equation   (1)   with   the   share   of   workers   with   different   levels   of   education   as   the   dependent  variable.  While  a  change  in  the  ERP  has  no  significant  impact  on  the  skill  composition  of   workers  in  non-­‐exporting  firms,  in  exporting  firms  a  decline  in  the  ERP  is  associated  with  an  increase   in  the  share  of  college-­‐educated  workers  and  a  decrease  in  the  share  of  workers  with  less  than  high   school  education.   19   !" !"#$ = !" + " ##"$$ % + # % "$ + $ & #$ + %"#$                                          (2)     where   i   indexes   the   individual,   j   indexes   the   firm,   t   indexes   time,   and   ln y ijt   denotes   individual-­‐level  log  wages.  The  panel  of  linked  worker-­‐firm  data  allows  us  to  control  for  a   rich  array  of  fixed  factors  that  may  influence  a  worker’s  wages,  in  addition  to  time-­‐varying,   € observable,  firm  characteristics  ( ! "# )  and  worker  characteristics  ( ! "# )  including  indicator   variables  for  the  worker’s  occupation,  age,  and  education,  as  well  as  the  worker’s  tenure  at   the   current   firm.   The   model   also   includes   individual   fixed   effects,   α ,   which   allow   us   to   i control   for   any   are   time-­‐invariant   unobservable   worker   characteristics,   and   firm   fixed   € effects,   ! j(i,t ) ,   for   firm   j   at   which   worker   i   is   employed   at   time   t,   representing   firm   heterogeneity.     Equation   (2)   could   then   be   augmented   to   include   sector   level   measures   of   protection   interacted   with   the   firm’s   export   status   in   order   to   test   the   contribution   of   unobservable  differences  across  workers  on  the  differential  response  to  trade  reform.           4.1  Endogenous  Worker  Mobility     It   is   important   to   note   that   the   identifying   assumption   for   equation   (2)   is   that   the   idiosyncratic  disturbance  term  in  each  period  is  independent  of  observable  worker  and  firm   characteristics  as  well  as  firm  and  worker  fixed-­‐effects.     E(!it | "i , ! j(i,t ), Xit , Z jt ) = 0     Often   referred   to   in   the   literature   as   the   assumption   of   “conditional   exogenous   mobility”   (see,  for  instance,  Abowd,  Kramarz,  and  Margolis  (1999),  Woodcock  (2008)  and  Soerensen   and   Vejlin   (2009)),   the   assumption   implies   that   employment   mobility   could   depend   on   time-­‐varying   observable   worker   or   firm   characteristics   and   firm   and   worker   fixed   effects,   but  not   !it .  This  assumption  is  at  odds  with  many  well-­‐known  models  of  the  labor  market   with   directed   search,   learning,   or   coordination   frictions.   For   example,   as   we   have   discussed   before,   in   Helpman,   Itskhoki,   and   Redding   (2010),   workers   are   ex   ante   identical   and   job   20   allocation  is  determined  on  the  basis  of  match  specific  ability  that  is  heterogenous  ex  post.   Furthermore,   high   productivity   firms   (exporters)   screen   more   intensively   resulting   in   higher   quality   firm-­‐worker   matches.   In   this   case   the   estimates   in   our   firm-­‐level   analyses   will  be  biased,  due  to  an  omitted  worker-­‐firm  match  effect.  Similarly,  if  workers  with  certain   observable  characteristics  are  more  successful  at  generating  good  matches  than  others  (for   example,   because   the   return   from   search   is   higher   or   due   to   learning)   and   hence   higher   wages,   omitted   match   effects   could   also   bias   the   estimated   returns   to   observable   characteristics  in  equation  (2).       We   test   the   validity   of   the   exogenous   mobility   assumption   using   the   “match   effects   test”   introduced   by   Abowd,   McKinney,   and   Schmutte   (2010).   The   test   statistic   is   based   on   estimated   match   effects   that   are   computed   from   the   average   (over   time)   residual   for   a   person   i   at   a   firm   j.   The   test   rests   on   the   logic   that   the   match   effect,   under   the   null   of   exogenous   mobility,   should   not   predict   the   transitions   of   workers   between   firms.   Specifically,   under   exogenous   mobility,   an   individual’s   average   residual,   !ijt!1   (within   quintiles   of   the   residual   distribution)   from   the   most   recently   completed   job   should   not   predict   the   transition   across   firms   with   heterogeneous   values   of   ! j(i,t ) (say   from   a   particular  quintile  of  the   ! j(i,t )  distribution  to  another).  The  test  is  implemented  as  follows.   First,   equation   (2)   is   estimated   for   the   full   sample   of   workers.   Then,   for   workers   who   switched   employers   between   time   t   and   t-­‐1,   the   average   residual   within   person   and   firm             ( !ijt!1 )   is   calculated   across   all   years   throughout   the   duration   of   the   match   (i.e.,   until   t-­‐1);   !ijt!1   represents   the   match   effect   for   the   firm   and   worker   pair.   Under   the   null   hypothesis,   the  transition  rates  across  quintiles  of  the  firm  effects  distribution,  from  the   ! j(i,t"1)  quintile   to   the   ! j(i,t )   quintile,   are   independent   of   !ijt!1 .   Importantly,   if   the   null   is   rejected   for   our   data,   this   would   suggest   that   the   estimation   results   from   equation   (2)   are   biased   and   that   firm-­‐worker   match   effects   should   be   included   in   the   specification   to   account   for   the   endogenous  mobility  of  workers.     In  constructing  the  test  statistic,  we  restrict  the  sample  to  those  workers  with  at  least  two   years  of  data  and  to  firms  in  the  manufacturing  sector.  Since  estimates  of  firm  fixed  effects   for   firms   with   only   few   movers   are   likely   to   be   imprecise,   Abowd,   Kramarz   and   Margolis   21   (1999)   suggests   grouping   small   firms   together   and   estimating   one   ! j(i,t )   for   these   firms   with   few   movers.   We   calculate   the   test   statistic   both   by   grouping   small   firms   with   less   than   two  movers  into  one  firm  and  by  excluding  these  small  firms  from  the  sample.  In  both  cases,   we  conduct  the  test  on  the  largest  mobility  group,  since  the  firm  fixed  effects  estimated  for   unconnected   groups   are   not   directly   comparable   with   each   other.35   Consistent   with   the   Abowd,   McKinney,   and   Schmutte   (2010)   finding   for   the   U.S.,   the   test   statistic   strongly   rejects  the  null  hypothesis  of  exogenous  mobility  for  the  sample  of  job  switchers  in  our  data.   2 The  match  effects  test  statistic  has  a  value   ! = 25, 000  and  is  distributed  chi-­‐sq  with  496   of  degrees  of  freedom  (and  thus  a  p-­‐value  of  0.000).36    This  finding  confirms  the  relevance  of   models   of   labor   allocation   involving   search   dynamics   or   other   frictions   (such   as   Helpman,   Itskhoki   and   Redding   (2010)   and   Davidson,   Matusz   and   Schevchenko   (2008))   and   highlights   the   importance   of   allowing   for   the   possibility   of   firm-­‐worker   match   heterogeneity  in  wage  determination  to  account  for  the  endogenous  mobility  of  workers.     To   further   emphasize   this   point,   we   plot,   in   Figure   4.1,   the   conditional   distribution   of   quintiles   of   the   firm   fixed   effects   for   the   previous   job,   ! j(i,t"1) ,   given   the   quintiles   of   the   individual’s   average   residual   from   the   most   recently   completed   job,   for   the   sample   of   job   changers.   Under   the   assumption   of   exogenous   mobility,   the   distribution   of   ! j(i,t"1)   should   not   show   any   variation   across   quintiles   of   the   average   residual.   That   is   to   say,   the   estimation  strategy  requires  that  the  quality  of  the  firm-­‐worker  match  in  the  previous  job   should   not   contain   any   information   about   the   estimated   firm-­‐fixed   effects   for   that   job.   Figure  4.1  clearly  demonstrates  that  this  is  not  the  case  in  our  data.  For  example,  while  the   job  changers  in  the  first  quintile  of  the  match  effect  (residual)  distribution  mostly  originate   from  the  second  quintile  of  the   ! j(i,t"1)  distribution,  most  switchers  in  the  second  quintile   of  the  match  effect  originate  from  the  first  quintile  of  the   ! j(i,t"1)  distribution.                                                                                                                       35   A   connected   group   includes   all   the   workers   who   have   ever   worked   for   any   of   the   firms   in   that   group   as   well   as   all   the   firms   at   which   any   of   these   workers   were   employed   at   during   the   sample   period.   Since   within   each   group   the   mean-­‐deviated   firm   fixed   effects   sum   to   zero,   the   estimates   of   ! !!" "# #   are   not   directly   comparable   across   unconnected   groups.   As   a   possible   solution,   one   can   normalize  the  fixed  effects  so  they  have  the  same  mean  across  groups  (Abowd,  Creecy,  and  Kramarz   (2002)).  Our  results  are  robust  to  using  the  full  sample  of  workers  and  correcting  the  fixed  effects  for   the  unconnected  groups  in  this  fashion.     36  The  degrees  of  freedom  are  calculated  as:   !"!!! #$"!!" #!" %$!&# #$"!!" #!" %$ # #!&#$"!!#"$!& #!&# =(5*5*5-­‐ " 1)*(5-­‐1)  where  #Q  denotes  the  number  of  quintiles.   22     In  Figure  4.2  we  plot  the  transition  rates  from  a  job  in  a  given   ! j(i,t"1)  quintile  to  a  job  in   ! j(i,t )   quintile,   again   for   the   sample   of   job   changers.   Here,   we   find   strong   evidence   that   job   transitions   are   not   random;   most   workers   move   between   jobs   within   the   same   employer-­‐ effect   quintile,   which   is   evident   from   the   rightward   movement   of   the   peak   of   the   ! j(i,t )   distribution   with   higher   quintiles   of   the   original   job.   Moreover,   Figure   4.3   clearly   illustrates   that   these   transition   probabilities   vary   considerably   by   different   quintiles   of   the   match   effect  distribution.  Figures  4.3a,  4.3b,  and  4.3c  plot  the  transition  probabilities  for  the  first,   third   and   fifth   quintiles   respectively,   of   the   residual   distribution.   For   example,   while   job   switchers   are   much   more   likely   to   improve   their   employer   effect   in   the   middle   and   (to   a   lesser  extent)  in  the  higher  end  of  the  residual  distribution,  we  find  this  not  to  be  the  case  in   the   first   quintile   of   the   match   effect   distribution.     This   illustrates   the   failure   of   the   exogenous  mobility  assumption  as  the  estimated  match  effects  clearly  contain  information   on  job-­‐to-­‐job  transitions  that  take  place  in  the  data.       Our  findings  on  endogenous  worker  mobility  have  interesting  implications  for  the  analysis   of   trade   and   labor   markets,   especially   since   the   workings   of   the   labor   market   have   been   modeled  in  a  number  of  different  ways  in  the  recent  literature  on  international  trade  with   heterogeneous   firms.   In   the   well-­‐known   paper   of   Melitz   (2003),   heterogeneous   monopolistically   competitive   firms   pay   their   (homogeneous)   workers   an   identical   wage,   with  the  assignment  of  particular  workers  to  firms  being  (effectively)  random.  Similarly,  in   Egger   and   Kreickemeier   (2009)   and   Amiti   and   Davis   (forthcoming),   the   assignment   of   workers   to   firms   is   random,   even   if   rent-­‐sharing   behavior   of   firms   implies   that   identical   workers   may   be   paid   different   wages,   based   on   the   profits   of   the   firms   in   which   they   are   employed.   The   decisive   rejection   of   the   assumption   of   exogenous   worker   mobility   in   our   data   supports   a   picture   of   the   labor   market   that   is   closer   in   line   with   the   framework   of   Helpman,  Itskhoki,  and  Redding  (2010),  where,  as  we  have  previously  discussed,  the  labor   allocation   process   is   subject   to   search   and   matching   frictions   and   the   equilibrium   assignment  of  workers  to  firms  is  clearly  non-­‐random.       4.2  Estimation  with  Match  Effects     23   If   match-­‐specific   effects   are   important   in   wage   determination,   the   Abowd,   Kramarz,   and   Margolis   (1999)   specification   in   equation   (2)   including   only   worker   and   firm   fixed   effects   will  result  in  both  biased  estimates  of  these  fixed  effects,  as  well  as  biased  estimates  of  the   returns  to  observable  worker  and  firm  characteristics  (Woodcock  (2008)).  For  example,  if   more  experienced  workers  are  likely  to  draw  better  matches,  omission  of  the  match  effect   will   result   in   an   over   estimation   of   the   returns   to   experience.   In   the   context   of   the   international   trade   literature,   if   the   labor   market   functions   in   the   manner   described   by   Helpman,  Itskhoki  and  Redding  (2010),  the  screening  thresholds  for  match-­‐specific  ability   will  be  different  in  the  resulting  equilibrium  after  liberalization,  shifting  the  distribution  of   worker   abilities   (i.e.,   the   quality   of   matches)   within   each   firm.   Given   that   this   shift   varies   systematically  with  the  export  status  of  the  firm,  not  controlling  for  match  quality  will  result   in   biased   estimates   of   the   differential   effect   of   trade   liberalization   on   wages   in   exporting   firms.     To  account  for  the  fact  that  a  worker’s  employment  history  may  not  be  independent  of  the   idiosyncratic   part   of   the   residual   in   equation   (2),   we   now   consider   a   more   elaborate   specification  of  wages,  in  which  worker-­‐firm  match  fixed  effects  (or  spell  fixed  effects),  Mij,   which   denote   a   given   worker   i’s   employment   at   a   given   firm   j,   are   included   on   the   right   hand  side:       !" !"#$ = !# $$ %$ + ! % $$ %$ & &'( #$ + ! ' $)&)$ & &'( #$ + ! ( $&'( #$ + *"# + "$+ + # , "$ + $ - #$ + %"#$                                    (3)     Note  that  since  for  each  spell  of  a  worker  within  a  firm  neither  the  worker  nor  the  firm  fixed   effect  varies,  inclusion  of  match  fixed  obviates  the  need  for  separate  inclusion  of  worker  and   firm  fixed  effects.       4.3  Estimation  Results       Table   4.1   includes   estimation   results   from   equation   (3)   with   spell   fixed   effects   with   both   tariffs  and  ERP  as  the  measure  of  protection.  Column  1  presents  results  with  tariffs  taken  as   the  measure  of  trade  protection  in  the  sector.  Our  results  suggest  that  the  inclusion  of  spell   fixed  effects  results  in  insignificant  estimates  of  both   ! ! " and   ! ! " .  The  insignificant  effect  of  a   decline   in   protection   on   both   exporters   and   firms   serving   the   domestic   market   also   holds   24   separately   for   the   high   and   low   comparative   advantage   sectors,   although   the   interaction   term   is   more   than   three   times   higher   in   magnitude   for   the   high   comparative   advantage   sector.   These   results   continue   to   hold   when   we   use   effective   rate   of   protection   in   the   sector   as  our  measure  of  trade  protection.       In  Table  4.2  we  present  a  wide  array  of  robustness  checks  we  have  conducted.  The  first  two   columns  report  estimation  results  from  specification  (3)  for  various  alternative  samples.  In   column   1,   we   use   a   5%   random   sample   of   males   in   metropolitan   areas   instead   of   a   1%   random   sample   of   the   full   population.   In   column   2   we   restrict   our   analysis   to   only   the   liberalization   period   (1990-­‐1994)   during   which   average   ERP   was   decreasing.   Our   results   are   robust   to   these   alternative   samples   and   to   using   an   industry-­‐specific   real   exchange   rate   measure   as   in   column   3,   instead   of   an   economy-­‐wide   measure.   Next,   we   test   whether   our   result  of  insignificant  interaction  coefficient  is  sensitive  to  the  exporting  thresholds  we  use   to  assign  the  indicator  variable  denoting  a  firm’s  export  status.  In  the  baseline  specifications   a  firm  is  defined  as  an  exporter  if  it  exported  a  positive  dollar  amount  that  year.  Instead,  in   columns  5  and  6,  we  only  consider  firms  with  an  export  value  more  than  the  5th  percentile   (cutoff   5),   and   more   than   the   10th   percentile   (cutoff   10)   as   exporting   firms,   respectively.   While   the   magnitude   of   the   interaction   term   increases   slightly   as   we   increase   the   cut   off   threshold,   the   coefficient   remains   statistically   insignificantly   different   than   zero.   In   the   next   two   columns   we   consider   two   time-­‐invariant   measures   of   export   status.   In   column   7,   a   firm   is  defined  as  an  exporter  if  it  exported  a  positive  dollar  value  at  the  beginning  of  our  sample   at   1990   (Export90).   The   export   status   variable   in   column   8   takes   the   value   1   if   the   firm   reported   positive   exports   during   every   year   between   90   and   98.   Finally,   when   we   use   the   magnitude   of   exports   for   the   sub-­‐sample   of   exporting   firms   to   represent   the   relevance   of   exports   to   the   firm   instead,   we   obtain   yet   again   estimates   of   ! ! " and   ! ! "   that   are   insignificantly  different  from  zero.37     Our  findings  using  worker  level  data  and  taking  endogenous  worker  mobility  into  account,   suggests   an   insignificant   differential   effect   of   trade   policy   on   the   wages   of   workers                                                                                                                   37   Other   robustness   checks   we   have   conducted   but   we   do   not   reported   to   conserve   space   include   defining   a   firm   as   exporter   if   the   firm   exported   only   to   non-­‐Mercosur   countries   (and   omitting   exporters  to  Mercosur  countries  from  the  sample)  and  using  a  more  detailed  industry  classification   available   only   for   the   1994-­‐1998   period,   which   allows   us   to   identify   changes   in   industry   level   ERP   at   a  more  disaggregated  level.  We  find  our  main  conclusions  to  be  robust.     25   employed   in   exporting   firms.   This   finding   stands   in   sharp   contrast   to   results   obtained   using   average   firm   level   wages   instead.   One   reason   for   this   difference   is   simply   that   the   use   of   detailed  worker  level  data  allows  us  to  take  into  full  account  any  changes  in  the  composition   of   the   workforce   (by   controlling   for   both   observable   and   time-­‐invariant   unobservable   worker   characteristics)   following   trade   policy.   Furthermore,   by   taking   worker-­‐firm   match   effects  into  account,  we  are  able  to  control  for  changes  in  the  composition  of  firms’  match   quality   following   trade   policy   changes.   If,   following   trade   liberalization,   exporting   firms   improve   their   average   match   quality   by   hiring   workers   with   better   match   quality,   the   estimates   of   the   coefficient   ! ! " without   controlling   for   match   effects   would   mistakenly   be   estimated  as  significant  even  in  the  absence  of  any  true  effect.       Table   4.3,   which   compares   the   changes   in   the   distribution   of   estimated   match   effects   in   exporting  firms  relative  to  non-­‐exporting  firms,  confirms  this  point.38  Comparing  the  period   1998  to  1990,  we  see  an  increase  in  both  the  mean  and  the  median  match  effect  in  exporting   firms,   while   the   mean   and   median   match   effect   both   fall   in   non-­‐exporting   firms.   As   we   have   noted  earlier,  match  fixed  effects  in  equation  (3)  absorb  both  worker  and  firm  fixed  effects   in  addition  to  time-­‐invariant  match  quality  of  a  given  employment  spell.  Consequently,  our   finding   of   an   improvement   in   average   match   effect   in   exporting   firms   between   1990   and   1998  summarizes  the  combined  effect  of  a  change  in  workforce  composition  in  these  firms   in  terms  of  improvement  in  worker  quality  in  time  invariant  worker  specific  characteristics,   such  as  innate  ability  (captured  by  worker  fixed  effects)  and  improvement  in  the  quality  of   the   worker-­‐firm   matches   (captured   by   match-­‐fixed   effects).39   The   improvement   in   the   distribution   of   match-­‐specific   ability   in   exporting   firms   is   consistent   with   the   Helpman,   Itskhoki,   Redding   (2010)   model   which   predicts   that   with   trade   liberalization,     exporting   firms   will   screen   more   intensively   and   set   a   higher   ability   threshold   for   employment.   It  is   also   roughly   in   line   with   the   prediction   of   Davidson,   Matusz,   and   Shevchenko   (2008)   that   greater  openness  leads  to  better  labor  market  sorting  of  higher  ability  workers  into  higher   technology   firms.   This   finding   serves   to   explain   the   difference   between   the   results   at   the   firm   level   and   those   at   the   worker   level:   If   average   quality   of   the   workforce   (in   terms   of   match   specific   ability   or   innate   (time-­‐invariant)   ability)   improves   systematically   in                                                                                                                   38  Table  4.3  is  for  a  group  of  firms,  which  were  included  in  our  sample  in  both  1990  and  1998  and  did   not  switch  export  status  during  this  period.     39   Note   that   firm-­‐fixed   effect   for   a   given   firm   is   constant   across   time   and   cannot   account   for   the   improvement  in  match  quality  between  1990  and  1998.     26   exporting   firms   following   trade   liberalization,   not   controlling   for   match   effects   (as   is   the   case   in   firm-­‐level   analysis),   will   incorrectly   suggest   that   trade   liberalization   leads   to   a   differential   wage   improvement   for   workers   at   exporting   firms   even   when   this   is   not   the   case.     A  comparison  of  estimates  obtained  from  specifications  with  and  without  spell  fixed  effects   suggests  that  match  effects  matter  both  qualitatively  and  quantitatively.  Table  4.4  compares   estimates   obtained   from   alternate   specifications   with   only   firm   fixed   effects,   with   both   worker   and   firm   fixed   effects   included,   and   finally   with   match   fixed   effects   included.   Note   that   this   comparison   can   only   be   made   for   the   sample   of   workers   who   switch   jobs   during   this   period,   as   worker   effects   cannot   be   separately   identified   from   match   effects   for   those   workers   who   do   not.   As   expected,   the   inclusion   of   worker   fixed   effects   lowers   (absolute   value  of)  the  magnitude  of   ! ! "  from  0.242  to  0.151  for  tariffs,  and  from  0.086  to  0.050  for   ERP   as   the   measure   of   protection.   The   inclusion   of   match   effects   lowers   the   coefficient   further   from   0.151   to   0.104   and   0.050   to   0.018,   when   the   measure   of   protection   is   tariffs   and  ERP,  respectively.       Finally,   Table   4.5   reports   estimates   of   ! ! " and   ! ! "   when   workers   with   different   levels   of   human   capital   (grouped   into   two   educational   categories   –   high   education   and   low   education)   are   examined   separately.   Interestingly,   there   are   heterogeneous   effects   across   the  two  educational  groups.  We  find  that  the  relative  wages  of  workers  with  higher  levels  of   education   employed   in   exporting   firms   improve   with   liberalization   compared   to   similar   workers   employed   in   firms   serving   the   domestic   market.   One   explanation   for   this   finding   is   that   the   rent   sharing   mechanism   we   have   discussed   earlier,   whereby   workers   share   a   fraction   of   the   profits   made   by   the   firms,   may   be   relevant   in   the   case   of   high   education   workers   even   it   remains   insignificant   in   workers   with   lower   levels   of   education.   Alternatively,   the   improvement   in   the   quality   of   the   labor   force   in   exporting   firms,   could   result   in   positive   productivity   spillovers   on   more   educated   workers   and   hence   higher   wages.               27   5.  Conclusions     In   this   paper,   we   use   a   linked   employer–employee   database   from   Brazil   to   examine   the   impact   of   trade   reform   on   the   wages   of   workers   employed   at   heterogeneous   firms.     Our   analysis   of   the   data   at   the   firm-­‐level  confirms  earlier  findings  of  a  differential  positive  effect   of   trade   liberalization   on   the   average   wages   at   exporting   firms   relative   to   non-­‐exporting   firms.   However,   this   analysis   of   average   firm-­‐level   wages   is   incomplete   along   several   dimensions.   First,   it   cannot   fully   account   for   the   impact   of   a   change   in   trade   barriers   on   workforce  composition  especially  in  terms  of  unobservable  (time-­‐invariant)  characteristics   of   workers   (innate   ability)   and   any   additional   productivity   that   obtains   in   the   context   of   employment   in   the   specific   firm   (match   specific   ability).   Furthermore,   the   firm-­‐level   analysis   is   undertaken   under   the   assumption   that   the   assignment   of   workers   to   firms   is   random.   This   ignores   the   sorting   of   worker   into   firms   and   leads   to   a   bias   in   estimates   of   the   differential   impact   of   trade   on   workers   at   exporting   firms   relative   to   non-­‐exporting   firms.   Using  detailed  information  on  worker  and  firm  characteristics  to  control  for  compositional   effects   and   using   firm-­‐worker   match   specific   effects   to   account   for   the   endogenous   mobility   of   workers,   we   find   the   differential   effect   of   trade   openness   on   wages   in   exporting   firms   relative   to   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 sub-­‐sample  of  firms,  we  can  combine  RAIS  with  data  from  the  Brazilian  manufacturing   survey,  Pesquisa  Industrial  Anual  (PIA).40  We  construct  an  indicator  variable  that  takes  the   value   one   if   a   firm   reports   positive   acquisitions   of   foreign   intermediate   goods   or   foreign   machinery.  This  measure  captures  acquisitions  by  firms  which  use  imported  intermediates   even  if  they  don’t  import  them  directly,  and  purchase  them  from  local  distributors  instead.   In   order   to   establish   a   comparison   with   our   results   for   the   full   sample,   we   start   by   replicating  our  main  specification  for  the  smaller  sample  of  firm-­‐groups  for  which  we  also   have  data  on  the  importer  status  of  the  firm.  We  find  the  differential  effect  on  exporters  to   be  prevalent  for  the  restricted  sample  of  PIA  firm-­‐groups  as  well.  Our  estimates  suggest  that   a  one  percentage  point  decrease  in  ERP  is  associated  with  an  increase  in  firm  average  wages   by   0.18%.   In   column   (2)   we   include   the   firm’s   importer   status   and   the   interaction   terms   between   importer   status   with   ERP   and   RER   in   our   main   specification.   Our   main   findings   on   the  differential  effect  of  liberalization  on  exporters  continue  to  hold  in  this  specification.  We   find   that   while   importing   firms   pay   higher   wages   on   average,   the   decline   in   ERP   does   not   have  a  differential  effect  on  importing  firms.     In  the  PIA  sample  there  is  significant  overlap  in  firms  that  export  and  import.  In  fact,   conditional   on   importing,   most   firms   also   export.   50   percent   of   firms   that   export   also   import,   while   only   11%   of   non-­‐exporters   import.   In   the   specification   reported   in   column   (3),   we   test   the   importance   of   this   overlap   on   our   results.   More   specifically,   we   define   an   exporter   dummy   which   takes   the   value   one   for   firms   that   export   but   do   not   import;   an   importer  dummy  which  takes  the  value  one  for  firms  that  import  but  do  not  export  and  an   exporter-­‐importer   dummy   which   takes   the   value   one   for   firms   that   both   export   and   import.41  The  differential  effect  of  a  change  in  ERP  on  exporters  is  significant  and  negative   for   firms   that   only   export   (and   do   not   import)   as   well   as   for   firms   that   both   export   and                                                                                                                   40  PIA   is   a   confidential   data   set,   based   on   a   survey   of   Brazilian   manufacturing   firms   conducted   annually   by   the   Brazilian   Census   Bureau   between   1986   to   the   present   (excluding   1991).   Since   we   do   not   have   access   to   this   confidential   dataset,   instead,   we   use   random   three-­‐to-­‐five   firm   cells   with   similar   characteristics,   constructed   by   Muendler   (2003)   to   meet   confidentiality   requirements.   The   data   we   use   are   based   on   these   random   aggregates   of   PIA   (firm-­‐groups)   as   described   in   Muendler   (2003)  and  Muendler  (2004).  In  our  discussion  of  the  PIA  data,  we  use  the  terms  “firms”  and  “firm-­‐ groups”  interchangeably.   41  Although  we  report  the  estimated  coefficients  for  column  (3)  in  the  same  row  as  columns  (1)  and   (2),  we  note  that  in  the  first  two  columns,  the  export  variable  takes  the  value  one  for  firms  that  report   positive  exports  and  the  import  variable  takes  the  value  one  for  firms  that  report  positive  imports.  In   column   (3),   the   export   and   import   variables   take   the   value   one   for   firms   that   export   but   do   not   import,  and  import  but  do  not  export,  respectively.   34   import.  We  find  no  differential  impact  of  a  decline  in  ERP  on  firms  that  only  import.  We  find   the   exporter-­‐premium   on   wages   to   be   higher   for   exporters   that   import,   compared   to   exporters   that   do   not.   The   higher   average   wages   for   importers   relative   to   domestic   firms   reported   in   column   (2)   seems   mainly   to   be   due   to   the   fact   that   most   of   these   firms   are   exporters  as  well.42                                                                                                                           We   note,   however,   that   there   is   heterogeneity   in   this   coefficient   based   on   the   comparative   42   advantage   of   the   firm’s   sector.   Unreported   results   suggest   that,   in   high   comparative   advantage   sectors,  a  decline  in  ERP  increases  wages  of  domestic  firms  using  imported  intermediates  relative  to   domestic   firms   which   do   not   use   imported   intermediates   (at   the   10%   level   of   significance);   a   one   percentage  point  decrease  in  ERP  increases  wages  at  high  comparative  advantage  importers  which   do   not   export   by   0.21%.   By   contrast,   average   wages   at   importers   which   do   not   export,   are   not   statistically   different   than   purely   domestic   firms   post-­‐liberalization   in   the   low   comparative   advantage   sector.   Moreover,   average   wages   at   exporters   (which   do   not   import)   and   exporter-­‐ importers  in  the  low  comparative  advantage  sector  increase  with  a  decline  in  ERP  relative  to  purely   domestic  firms.  These  results  are  available  upon  request.   35   Figure  3.1  Time  Variation  in  Effective  Rates  of  Protection,  1990-­‐1998       0.60   0.50   0.40   0.30   0.20   0.10   0.00   1988   1989   1990   1991   1992   1993   1994   1995   1996   1997   1998   Average  ERP   Median  ERP     36 Figure  3.2:   Cross-­Industry  Variation  in  Effective  Rates  of  Protection                   Effective  Rates  of  Protection  in  1990                    Effective  Rates  of  Protection  in  1998                                      Annual  Change  in  ERP,  1990-­‐1998   Source:  Kume,  Piani,  and  Souza  (2003).       37 Figure  4.1  Distribution  of  Psi  ( Ψj(i,t ))  Quintile  by  Residual  ( ε ijt −1)  Quintile   € € 35   30   30-­‐35   25   25-­‐30   20   20-­‐25   15-­‐20   15   10-­‐15   10   Residual_5   Residual_4   5-­‐10   5   Residual_3   0-­‐5   0   Residual_2   psi_lag=1   psi_lag=2   psi_lag=3   Residual_1   psi_lag=4   psi_lag=5     Figure  4.2  Probability  of  Transition  to  Each  Quintile  of  the  Psi  ( Ψj(i,t ))  Distribution,  by   Psi  ( Ψj(i,t −1))  Quintile  of  Origin,  Full  Sample  of  Job  Changers   € € 0.5   0.45   0.4   0.35   psi_lag=1   0.3   psi_lag=2   0.25   psi_lag=3   0.2   psi_lag=4   0.15   psi_lag=5   0.1   psi_lag=5   psi_lag=4   0.05   psi_lag=3   0   psi_lag=2   psi=1   psi=2   psi_lag=1   psi=3   psi=4   psi=5         38 Figure  4.3  Probability  of  Transition  to  Each  Quintile  of   Ψj(i,t )  ,    by   Ψj(i,t −1)  Quintile   Figure  4.3a  Job  Changers  in  Q( ε ijt −1)=1   € € 50   € 40   40-­‐50   30   30-­‐40   20   20-­‐30   psi_lag=5   10-­‐20   10   psi_lag=3   0-­‐10   0   psi=1   psi=2   psi=3   psi_lag=1   psi=4   psi=5     Figure  4.3b  Job  Changers  in  Q( ε ijt −1)=3   50   € 40   40-­‐50   30   30-­‐40   20   20-­‐30   psi_lag=5   10-­‐20   10   psi_lag=3   0-­‐10   0   psi=1   psi=2   psi=3   psi_lag=1   psi=4   psi=5     Figure  4.3c  Job  Changers  in  Q( ε ijt −1)=5   50   € 40   40-­‐50   30   30-­‐40   20   20-­‐30   psi_lag=5   10-­‐20   10   psi_lag=3   0-­‐10   0   psi=1   psi=2   psi=3   psi_lag=1   psi=4   psi=5     39 Table  2.1  Descriptive  Statistics Sample Exporters Domestic Worker  Characteristics Average  Wage  in  reais 3,917 5,512 2,456 Average  Log  (Wages) 7.630 8.019 7.273 Share  of  Workers Less  than  High  School 0.745 0.696 0.790 High  School  Graduates 0.184 0.206 0.164 College  Graduates 0.066 0.094 0.039 Unskilled  Blue  Collar 0.109 0.099 0.119 Skilled  Blue  Collar   0.609 0.599 0.617 Other  White  Collar   0.078 0.079 0.077 Professional  and  Managerial 0.179 0.206 0.154 Firm  Characteristics Average  Employment 73 346 37 Average  Log  (Employment) 2.82 4.75 2.57 Number  of  Workers 114,042 64,212 80,895 Number  of  Firms 58,578 11,143 53,537 40 Table  3.1  Trade  Protection  and  Firm-­‐Level  Average  Wages Tariffs ERP  High   Low    High   Low   Full  Sample Comparative   Comparative   Full  Sample Comparative   Comparative   Advantage Advantage Advantage Advantage 0.170** -­‐0.058 0.279*** Tariff (0.079) (0.182) (0.095) -­‐0.248*** -­‐0.562*** -­‐0.117 Export*Tariff (0.074) (0.109) (0.094) -­‐0.011 -­‐0.082* 0.067 ERP (0.033) (0.045) (0.046) -­‐0.103*** -­‐0.206*** -­‐0.008 Export*ERP (0.037) (0.054) (0.064) -­‐0.258*** -­‐0.293*** -­‐0.230*** -­‐0.233*** -­‐0.247*** -­‐0.199** Export*RER (0.058) (0.076) (0.081) (0.055) (0.074) (0.081) 0.328*** 0.414*** 0.275*** 0.279*** 0.318*** 0.219** Export (0.074) (0.094) (0.104) (0.067) (0.088) (0.100) N 505,369 258,374 246,995 505,369 258,374 246,995 Firm-­‐Fixed  Effects YES YES YES YES YES YES Region-­‐Specific  Year  Dummies YES YES YES YES YES YES Detailed  Firm-­‐Level  Controls YES YES YES YES YES YES Impact  on  Exporters Tariff -­‐0.078 -­‐0.620*** 0.162 -­‐0.114** -­‐0.289*** 0.058 F-­‐Statistic 0.50 9.37 1.40 4.86 14.58 0.59 p-­‐value 0.48 0.00 0.24 0.03 0.00 0.45 41 Table  3.2  ERP  and  Firm-­‐Level  Wages:  Robustness Alternative  Samples Export  Status Industry   Size  of   Balanced   5%  Metro   Lib.  period   Specific  RER Cutoff5 Cutoff10 Export90 Export_All Exports Panel Sample 90-­‐94 0.004 -­‐0.021 -­‐0.000 -­‐0.031 -­‐0.011 -­‐0.011 -­‐0.013 -­‐0.001 0.284*** ERP (0.038) (0.033) (0.029) (0.031) (0.033) (0.033) (0.034) (0.033) (0.091) -­‐0.095** -­‐0.083** -­‐0.125*** -­‐0.055* -­‐0.108*** -­‐0.110*** -­‐0.115*** -­‐0.086** -­‐0.025*** Export*ERP (0.042) (0.033) (0.034) (0.031) (0.038) (0.039) (0.042) (0.037) (0.007) -­‐0.009*** -­‐0.210*** -­‐0.098*** -­‐0.005*** -­‐0.233*** -­‐0.238*** -­‐0.261*** -­‐0.190*** -­‐0.022*** Export*RER (0.002) (0.050) (0.032) (0.001) (0.056) (0.056) (0.057) (0.046) (0.008) 0.284*** 0.251*** 0.145*** 0.466*** 0.279*** 0.283*** 0.034*** Export (0.067) (0.060) (0.039) (0.060) (0.067) (0.068) (0.010) N 204,437 354,564 270,400 505,369 505,369 505,369 505,369 505,369 58,418 Firm-­‐Fixed  Effects YES YES YES YES YES YES YES YES YES Region-­‐Specific  Year   YES YES YES YES YES YES YES YES YES Dummies Detailed  Firm-­‐Level   YES YES YES YES YES YES YES YES YES Controls 42 Table  4.1  Trade  Protection  and  Worker-­‐Level  Wages Tariffs ERP  High   Low    High   Low   Full  Sample Comparative   Comparative   Full  Sample Comparative   Comparative   Advantage Advantage Advantage Advantage Tariff 0.133 -­‐0.018 0.273 (0.177) (0.300) (0.256) Export*Tariff -­‐0.110 -­‐0.180 -­‐0.055 (0.090) (0.129) (0.127) ERP -­‐0.020 -­‐0.083 0.198 (0.073) (0.074) (0.130) Export*ERP -­‐0.045 -­‐0.042 0.004 (0.045) (0.051) (0.074) Export 0.133* 0.067 0.184 0.113* 0.024 0.154 (0.072) (0.074) (0.125) (0.061) (0.064) (0.115) Export*RER -­‐0.094* -­‐0.025 -­‐0.147 -­‐0.085* -­‐0.004 -­‐0.132 (0.056) (0.059) (0.095) (0.051) (0.055) (0.091) N 504,424 266,463 237,961 504,424 266,463 237,961 Detailed  Worker  Level  Controls YES YES YES YES YES YES Detailed  Firm  Level  Controls YES YES YES YES YES YES Region-­‐Specific  Year  Dummies YES YES YES YES YES YES Spell-­‐Fixed  Effects YES YES YES YES YES YES 43 Table  4.2  ERP  and  Worker-­‐Level  Wages:  Robustness Alternative  Samples Export  Status Liberalizatio Industry   Size  of   5%  Metro   n  period  90-­‐ Specific  RER cutoff5 cutoff10 Export90 Export_All Exports Male  Sample 94 ERP -­‐0.044 -­‐0.040 -­‐0.025 -­‐0.015 -­‐0.012 -­‐0.026 -­‐0.030 -­‐0.170 (0.059) (0.092) (0.074) (0.073) (0.073) (0.072) (0.074) (0.196) Export*ERP -­‐0.031 -­‐0.046 -­‐0.035 -­‐0.054 -­‐0.058 -­‐0.037 -­‐0.021 0.007 (0.050) (0.045) (0.044) (0.046) (0.044) (0.047) (0.040) (0.015) Export 0.054 0.076 -­‐0.003*** 0.115* 0.122** 0.006 (0.055) (0.058) (0.001) (0.062) (0.062) (0.012) Export*RER -­‐0.019 -­‐0.053 -­‐0.003*** -­‐0.084 -­‐0.089* -­‐0.099** -­‐0.024 0.001 (0.047) (0.051) (0.001) (0.051) (0.051) (0.043) (0.026) (0.009) N 447,957 269,951 504,424 504,424 504,424 504,424 504,424 241,147 Detailed  Worker  Level  Controls YES YES YES YES YES YES YES YES Detailed  Firm  Level  Controls YES YES YES YES YES YES YES YES Region-­‐Specific          Year  Dummies YES YES YES YES YES YES YES YES Spell-­‐Fixed  Effects YES YES YES YES YES YES YES YES 44 Table  4.3  Change  in  Estimated  Match  Effects  Over  Time Match  Effect 1990 1998 Median Mean Median Mean Exporters 0.145 0.135 0.169 0.160 Non-­‐exporters 0.018 -­‐0.019 -­‐0.056 -­‐0.068 All  Firms 0.065 0.031 0.059 0.034 45 Table  4.4  Alternative  Specifications  for  Switchers Tariffs ERP Both  Firm   Both  Firm   Only  Firm   Match  Fixed   Only  Firm   Match  Fixed   and  Worker   and  Worker   Fixed  Effects Effects Fixed  Effects Effects Fixed  Effects Fixed  Effects Tariff 0.552*** 0.158* 0.056 (0.180) (0.149) (0.232) Export*Tariff -­‐0.242* -­‐0.151** -­‐0.104 (0.124) (0.092) (0.101) ERP 0.087 0.020 -­‐0.011 (0.084) (0.063) (0.095) Export*ERP -­‐0.086 -­‐0.050 -­‐0.018 (0.070) (0.050) (0.058) Export 0.255*** 0.182 0.133 0.198** 0.144 0.098 (0.094) (0.074) (0.083) (0.086) (0.066) (0.076) Export*RER -­‐0.140* -­‐0.117** -­‐0.089 -­‐0.109 -­‐0.097 -­‐0.071 (0.072) (0.057) (0.066) (0.070) (0.054) (0.063) N 226,193 226,193 226,193 226,193 226,193 226,193 Firm  Controls YES YES YES YES YES YES Worker  Controls YES YES YES YES YES YES Firm  Fixed  Effects YES YES NO YES YES NO Worker  Fixed  Effects NO YES NO NO YES NO Spell-­‐Fixed  Effects NO   NO YES NO   NO YES Table  4.5  ERP  and  Worker  Level  Wages,  by  Skill Less  than   More  than   High-­‐School High-­‐School ERP -­‐0.005 -­‐0.055 Export*ERP -­‐0.035 -­‐0.094* Export 0.116* 0.127 Export*RER -­‐0.088 -­‐0.088 Firm  Controls YES YES Worker  Controls YES YES Spell-­‐Fixed  Effects NO   NO 46 Table  A.1  ERP  and  Firm-­‐Level  Wages:  Importers  and  Exporters Only  Export   Export  and   Detailed  Trade   Status Import  Status Status 0.090 0.084 0.089 ERP (0.073) (0.074) (0.072) -­‐0.178*** -­‐0.175*** -­‐0.185*** Export*ERP (0.036) (0.038) (0.045) -­‐0.154*** -­‐0.117** -­‐0.088* Export*RER (0.051) (0.051) (0.051) 0.226*** 0.184*** 0.163** Export (0.064) (0.065) (0.065) 0.128*** -­‐0.034 Import (0.042) (0.135) 0.001 -­‐0.034 Import*ERP (0.042) (0.135) -­‐0.112*** 0.065 Import*RER (0.034) (0.101) -­‐0.175*** Export_Import  *ERP (0.045) -­‐0.219*** Export_Import  *RER (0.050) 0.306*** Export_Import (0.064) N 11,372 11,372 11,372 Firm-­‐Fixed  Effects YES YES YES Year  Dummies YES YES YES Detailed  Firm-­‐Level  Controls YES YES YES 47