Verti-zontal differentiation in export markets
提出新模型区分出口中的水平差异化（口味）与垂直差异化（质量），并用比利时企业产品层面数据验证，对研究出口绩效的学者有用。
Many trade models of monopolistic competition identify cost efficiency as the main determinant of firm performance in export markets. To date, the analysis of demand factors has received much less attention. We propose a new model where consumer preferences are asymmetric across varieties and heterogeneous across countries. The model generates new predictions and allows for an identification of horizontal differentiation (taste) clearly distinguished from vertical differentiation (quality). Data patterns observed in Belgian firm-product level exports by destination are congruent with the predictions and seem to warrant a richer modelling of consumer demand.