We discuss a unified theory of directed technological change and technology adoption that can shed light on the causes of persistent productivity differences across countries. In our model, new technologies are designed in advanced countries and diffuse endogenously to less developed countries....

We analyse the implications for the dynamics of capital accumulation of market power and endogenous demand elasticities, in an environment in which the latter are affected by the number of competitors in each industry. In equilibrium the interest rate increases as capital accumulates, even...