The case against patents
The case against patents can be summarized briefly: there is no empirical evidence that they serve to increase innovation and productivity. There is strong evidence, instead, that patents have many negative consequences.
Factor saving innovation
We study a simple model of factor saving technological innovation in a concave framework. Capital can be used either to reproduce itself or, at additional cost, to produce a higher quality of capital that requires less labor input. If higher quality capital can be produced quickly, we get a model of exogenous balanced growth as a special case. If, however, higher quality capital can be produced slowly, we get a model of endogenous growth in which the growth rate of the economy and the rate of adoption of new technologies are determined by preferences, technology, and initial conditions. ...
Reconstructing the great recession
This paper evaluates the role of the construction sector in accounting for the performance of the U.S. economy before, during and after the Great Recession. We use input-output analysis to evaluate its linkages with the rest of the economy and measure the transmission of its demand shocks to the overall economy. Such effects are quantified by means of a dynamic multi-sector model parameterized to reproduce the boom-bust dynamics of employment in construction during 2000-13. The model suggests that the interlinkages account for a large share of the actual changes in aggregate employment and ...
The economics of ideas and intellectual property
Innovation and the adoption of new ideas are fundamental to economic progress. Here we examine the underlying economics of the market for ideas. From a positive perspective, we examine how such markets function with and without government intervention. From a normative perspective, we examine the pitfalls of existing institutions, and how they might be improved. We highlight recent research by ourselves and others challenging the notion that government awards of monopoly through patents and copyright are ?the way? to provide appropriate incentives for innovation.
Habit persistence, asset returns and the business cycle
We introduce two modifications into the standard real business cycle model: habit persistence preferences and limitations on intersectoral factor mobility. The resulting model is consistent with the observed mean equity premium, mean risk free rate and Sharpe ratio on equity. The model does roughly as well as the standard real business cycle model with respect to standard measures. On four other dimensions its business cycle implications represent a substantial improvement. It accounts for (i) persistence in output, (ii) the observation that employment across different sectors moves together ...
Habit persistence, asset returns and the business cycles
We introduce two modifications into the standard real business cycles model: habit persistence preferences and limitations on intersectoral mobility. The resulting model is consistent with the observed mean equity premium, mean risk free rate and Sharpe ration on equity. With respect to the conventional measures of business cycle volatility and comovement, the model does roughly as well as the standard real business cycle model. On four other dimensions its business cycle implications represent a substantial improvement. It accounts for (i) persistence in output, (ii) the observation that ...
Reconstructing the Great Recession
This article uses dynamic equilibrium input-output models to evaluate the contribution of the construction sector to the Great Recession and the expansion preceeding it. Through production interlinkages and demand complementarities, shifts in housing demand can propagate to other economic sectors and generate a large and sustained aggregate cycle.
What happened to the US stock market? Accounting for the last 50 years
The extreme volatility of stock market values has been the subject of a large body of literature. Previous research focused on the short run because of a widespread belief that, in the long run, the market reverts to well understood fundamentals. Our work suggests this belief should be questioned as well. First, we show actual dividends cannot account for the secular trends of stock market values. We then consider a more comprehensive measure of capital income. This measure displays large secular fluctuations that roughly coincide with changes in stock market trends. Under perfect foresight, ...
Habit persistence and asset returns in an exchange economy
We examine asset prices and returns in the context of a version of the pure exchange economy studied in Lucas (1978) and Mehra and Prescott (1985). Our purpose is to identify the key channels by which changes in preferences affect the equity premium and the risk free rate and to develop intuition that is useful for understanding asset pricing in more complicated economies. Our analysis suggests that capital gains play a crucial role in generating empirically plausible mean equity premia.
Growth cycles and market crashes
Market booms are often followed by dramatic falls. To explain this requires an asymmetry in the underlying shocks. A straightforward model of technological progress generates asymmetries that are also the source of growth cycles. Assuming a representative consumer, we show that the stock market generally rises, punctuated by occasional dramatic falls. With high risk aversion, bad news causes dramatic increases in prices. Bad news does not correspond to a contraction of existing production possibilities, but to a slowdown in their rate of expansion. This economy provides a model of endogenous ...