Hartman (1972) and Abel (1983) showed that when firms are competitive and there is flexibility of labour relative to capital, marginal profitability of capital is a convex function of the stochastic variable (e.g., price); by Jensen’s inequality, this means that uncertainty increases the...

This paper revisits the results of the pioneering models of the firm under demand uncertainty and analyses the apparent disparity with respect to the signal of the investment-uncertainty relationship predicted by them. In the 1970’s-1980’s the modelling of demand uncertainty at the firm...

We develop a multi-sector model of R&D-driven endogenous growth that merges the expanding-variety with the quality-ladders mechanism. The mechanism of expanding variety provides the flow of new firms (new product lines), whilst the mechanism of quality ladders provides the accumulation of...

We revisit the issue of self-fulfilling “waves of enthusiasm” as stationary rational expectations equilibrium outcomes in endogenous-growth models that merge the quality-ladders with the expanding-variety mechanism. By considering a lab-equipment specification with vertical-innovation...

This paper develops a tournament model of horizontal and vertical R&D under a lab-equipment specification. A key feature is that the overall growth rate is endogenous, as the splitting of the growth rate between the intensive and the extensive margin is itself endogenous. This setup gives rise...

This paper investigates the reasons why firms use fixed-term contracts.Two distinctive features of these contracts - reduced firing costs and the prohibition of contract rollover - are highlighted. Firms' decision related to temporary contracts - the choice of the contract on offer and contract...

In this paper we study the performance reaction of investors in a small market context. Instead of the asymmetrical investors’ reaction to winners and losers, as usually documented for the US, an absence of risk-adjusted performance reaction was observed. The absence of reaction can be...

Based on a comprehensive theoretical model we investigate the determinants of government spending. Besides GDP, commonly associated with either Walra´s law or Keynesian macro stabilization policies, we consider some variables identified with the public choice approach, namely median voters,...

This paper contributes to the scarce empirical literature on the impact of foreign ownership on human capital intensity. New evidence is provided, based on a comprehensive, large-scale survey of technology-based firms located in Portugal. Using two alternatives measures of human capital (one...

The model that we develop here considers that an upstream firm sells a vital input to downstream firms. There are vertical spillovers and two different regulatory policies of the input price: cost oriented regulation and no-regulation. We also admit two alternative market structures: vertical...