A mutual-fund manager is more likely to hold (or buy, or sell) a particular stock in any quarter if other managers in the same city are holding (or buying, or selling) that same stock. This pattern shows up even when controlling for the distance between the fund manager and the stock in...

We develop a model that clarifies the respective advantages and disad- vantages of academic and private-sector research. Our model assumes full protection of intellectual property rights at all stages of the development process, and hence does not rely on lack of appropriability or spillovers to...

We use a simple model to outline the conditions under which corporate investment will be sensitive to non-fundamental movements in stock prices. The key cross-sectional prediction of the model is that stock prices will have a stronger impact on the investment of firms that are “equity...

We examine some basic data on the evolution of aggregate short interest, both during the dot-com era, and at other times in history. Total short interest moves in a countercyclical fashion. For example, short interest in NASDAQ stocks actually declines as the NASDAQ index approaches its peak....

We build a model that helps explain why increases in liquidity-such as lower bid-ask spreads, a lower price impact of trade, or higher turnoverpredict lower subsequent returns in both firm-level and aggregate data. The model features a class of irrational investors, who underreact to the...

We postulate that agents make forecasts using overly simplified models of the world—i. e. , models that only embody a subset of available information. We then go on to study the implications of learning in this environment. Our key premise is that learning is based on a model-selection...

Theory suggests that, in the presence of local bias, the price of a stock should be decreasing in the ratio of the aggregate book value of firms in its region to the aggregate risk tolerance of investors in its region. We test this proposition using data on U. S. Census regions and states, and...

Theories based on incomplete contracting suggest that small organizations may do better than large organizations in activities that require the processing of soft information. We explore this idea in the context of bank lending to small firms, an activity that is typically thought of as relying...