Which Portuguese Manufacturing Firms Learn by Exporting?

Using a longitudinal database (1996-2003) at the plant level, this paper aims to shed light on the causal nexus between international trade engagement and productivity in Portugal. We analyse in particular the learning-by-exporting hypotheses. In line with recent empirical literature, we apply mainly the Propensity Score Matching and a differences-in-differences estimator. In post-entry years we find a higher growth of labour productivity and total factor productivity for new exporting firms when compared to firms that, although having similar characteristics, have decided not to begin exporting in that year. Moreover, in an attempt to uncover the channels through which the learning effects are driven to new exporters, we applied the same methodology to some sub-samples. We found that learning effects are higher for new exporters that are also importers or start importing at the same time. Other important factors influencing that learning ability are found in firms that export to more developed markets, in those that achieve a certain threshold of export intensity and particularly for those firms that belong to sectors in which Portugal is at a comparative disadvantage