Knowledge that Transforms

ABSTRACT This paper develops a simple technique that controls for “false discoveries,” or mutual funds that exhibit significant alphas by luck alone. Our approach precisely separates funds into (1) unskilled, (2) zero‐alpha, and (3) skilled funds, even with dependencies in cross‐fund estimated alphas. We find that 75% of funds exhibit zero alpha (net of expenses), consistent with the Berk and Green equilibrium. Further, we find a significant proportion of skilled (positive alpha) funds prior to 1996, but almost none by 2006. We also show that controlling for false discoveries substantially improves the ability to find the few funds with persistent performance.

ABSTRACT Individual investors lose money around earnings announcements, experience poor posttrade returns, exhibit the disposition effect, and make contrarian trades. Using simulations and trading records of all individual investors in Finland, I find that these trading patterns can be explained in large part by investors' use of limit orders. These patterns arise mechanically because limit orders are price‐contingent and suffer from adverse selection. Reverse causality from behavioral biases to order choices does not appear to explain my findings. I propose a simple method for measuring a data set's susceptibility to this limit order effect.

ABSTRACT We develop a technique to assess the impact of changes in mortgage markets on households, exploiting an implication of the permanent income hypothesis: The higher a household's expected future income, the higher its desired consumption, ceteris paribus. With perfect credit markets, desired consumption matches actual consumption and current spending forecasts future income. Because credit market imperfections mute this effect, the extent to which house spending predicts future income measures the “imperfectness” of mortgage markets. Using micro‐data, we find that since the early 1980s, mortgage markets have become less imperfect in this sense, and securitization has played an important role.

ABSTRACT The paper tests whether individuals have value‐relevant information about local stocks (where “local” is defined as being headquartered near where an investor lives). Our methodology uses two types of calendar‐time portfolios—one based on holdings and one based on transactions. Portfolios of local holdings do not generate abnormal performance (alphas are zero). When studying transactions, purchases of local stocks significantly underperform sales of local stocks. The underperformance remains when focusing on stocks with potentially high levels of information asymmetries. We conclude that individuals do not help incorporate information into stock prices. Our conclusions directly contradict existing studies.