The Elusive Pro-Competitive Effects of Trade
研究了垄断竞争、企业异质性和可变加成率模型中的贸易自由化收益，发现可变加成率模型预测的收益最多等于、最差略低于恒定加成率模型，表明贸易的促进竞争效应难以捉摸。
We study the gains from trade liberalization in models with monopolistic competition, firm-level heterogeneity, and variable markups. For a large class of demand functions used in the international macro and trade literature, we derive a parsimonious generalization of the welfare formula in Arkolakis et al. (2012). We then use both estimates from micro-level trade data and evidence regarding firm-level pass through to quantify the implications of this new formula.Within the class of models that we consider, our main finding is that gains from trade liberalization predicted by models with variable markups are equal to, at best, and slightly lower than, at worst, those predicted by models with constant markups. In this sense, pro-competitive effects of trade are elusive.