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...

In this paper, we examine the studies, since Adam Smith, on the impact of commercial and technological aspects, resulting from international trade, on the physical accumulation and quality of productive factors. We remark that the theory of economic growth and the theory of international trade,...

The Perpetual Inventory Model (PIM) assumes that, in each period, an arbitrary constant fraction of technological-knowledge stock is lost. By connecting the aggregate resource constraint with firms’ market value, we give a theoretical background to the PIM by showing that the...

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...

The purpose of this paper is to develop a model of innovation and learning that incorporates explicitly the need for a firm to conduct its own R&D in order to realize involuntary spillovers from other firms’ R&D activity, and the development of absorptive capacity of research firms over time....

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...