This note provides a simple exposition of what IV can and cannot estimate in a model with a binary treatment variable and heterogeneous treatment effects. It shows how linear IV is a misspecification of functional form and the reason why linear IV estimates for this model will always depend on...

This paper documents the convergence of incomes across Indian states over the period 1965 to 1998. It departs from traditional analyses of convergence by tracking the evolution of the entire income distribution, instead of standard regression and time series analyses. The findings reveal...

Equilibrium models have been proposed in literature with the aim of describing the evolution of the price of emission permits. This paper derives first a reducedform model from an equilibrium model and thereby explains how existing reducedform models are related to equilibrium models. Second, by...

This paper uses a difference-in-difference style estimation strategy to test separately the impact of competition from public sector and private sector hospitals on the efficiency of public hospitals. Our identification strategy takes advantage of the phased introduction of a recent set of...

This paper examines whether or not hospital competition in a market with fixed reimbursement prices can prompt improvements in clinical quality. In January 2006, the British Government introduced a major extension of their market-based reforms to the English National Health Service. From January...

Certain recently reported statistical regularities relating to the dispersion of firms' growth rates have begun to attract attention among IO economists. These relationships take the form of power law or scaling relationships and this has led to suggestions that the underlying mechanisms which...

Case study evidence suggests that exporting firms learn from their clients. But econometric evidence, mostly using exporting and TFP growth, is mixed. We use a UK panel data set with firm-level information on exporting and productivity. Our innovation is that we also have direct data on the...

We build a model of firm-level innovation, productivity growth and reallocation featuring endogenous entry and exit. A key feature is the selection between high- and low-type firms, which differ in terms of their innovative capacity. We estimate the parameters of the model using detailed US...

After some decades of relative oblivion, the interest in the optimality properties of monopolistic competition has recently re-emerged due to the availability of an appropriate and parsimonious framework to deal with firm heterogeneity. Within this framework we show that non-separable utility,...

In this paper we discuss some of the most important economic issues raised in European Commission vs. Microsoft (2004) concerning the market for work group servers. In our view, the most important economic issues relate to (a) foreclosure incentives and (b) innovation effects of the proposed...