How product innovation in the North may immiserize the South : A new look at the Ricardian model with a continuum of goods

The paper proposes a theoretical model investigating the welfare consequences of technological shocks in a Ricardian framework (a la Dornbush, Fisher and Samuelson, 1977). Contrary to the existing literature, the model incorporates a nonhomothetic demand function whose price and income elasticities are endogenously determined by technology. Nonhomothetic preferences are modeled as the result of the hierarchical consumption of luxury and necessity goods. The nature of technical progress determines the consumption pattern and notably the magnitude of the substitution effect between necessities and luxuries. The model is applied to the case of trade between two economies with different development levels. It is shown in particular that the developing country can suffer a fall in utility as a result of technical progress in the developed country biased towards luxury goods. This configuration depends on the size of the development gap and reflects the fact that Southern goods are less attractive, the higher the range of goods consumed. This result suggests that there is an optimal level of development gap to avoid LDCs being harmed by technical progress in the North.