What Drives the Disposition Effect? An Analysis of a Long‐Standing Preference‐Based Explanation

We investigate whether prospect theory preferences can predict a disposition effect. We consider two implementations of prospect theory: in one case, preferences are defined over annual gains and losses; in the other, they are defined over realized gains and losses. Surprisingly, the annual gain/loss model often fails to predict a disposition effect. The realized gain/loss model, however, predicts a disposition effect more reliably. Utility from realized gains and losses may therefore be a useful way of thinking about certain aspects of individual investor trading.     

Sequential Learning,Predictability, and Optimal Portfolio Returns

This paper finds statistically and economically significant out‐of‐sample portfolio benefits for an investor who uses models of return predictability when forming optimal portfolios. Investors must account for estimation risk, and incorporate an ensemble of important features, including time‐varying volatility, and time‐varying expected returns driven by payout yield measures that include share repurchase and issuance. Prior research documents a lack of benefits to return predictability, and our results suggest that this is largely due to omitting time‐varying volatility and estimation risk. We also document the sequential process of investors learning about parameters, state variables, and models as new data arrive.     

Independent invention during the rise of the corporate economy in Britain and Japan1

Independent inventors accounted for approximately half of all patents in Britain and Japan by 1930, despite the rise of the corporate economy and the spread of industrial R&D. A mixture of patent renewal and historical citations data reveals that the quality of independent invention was high. Active markets for inventions created incentives for independents, especially in large cities like London and Tokyo, which dominated spatially. Alongside evidence for the US, the findings show that in countries with different patent systems and at varying stages of economic development, a key component of overall inventive activity originated from outside the boundaries of firms.