This paper studies two frequently observed portfolio behaviors that are seemingly inconsistent with rational portfolio choice. The first is the tendency of workers and entrepreneurs to hold their company's stock. The second is the propensity of workers to limit their equity holdings through...

We build a market equilibrium theory of asset prices under Knightian uncertainty. Adopting the mean-variance decisionmaking model of Maccheroni, Marinacci, and Ruffino (2013a), we derive explicit demands for assets and formulate a robust version of the two-fund separation theorem. Upon market...

We build a market equilibrium theory of asset prices under Knightian uncertainty. Adopting the mean-variance decisionmaking model of Maccheroni, Marinacci, and Ruffino (2013a), we derive explicit demands for assets and formulate a robust version of the two-fund separation theorem. Upon market...

This paper studies two frequently observed portfolio behaviors that are seemingly inconsistent with rational portfolio choice. The first is the tendency of workers and entrepreneurs to hold their company's stock. The second is the propensity of workers to limit their equity holdings through...

We derive the analogue of the classic Arrow-Pratt approximation of the certainty equivalent under model uncertainty as defined by the smooth model of decision making under ambiguity of Klibanoff, Marinacci and Mukerji (2005). We study its scope via a portfolio allocation exercise that delivers a...

This paper studies two frequently observed portfolio behaviors that are seemingly inconsistent with rational portfolio choice. The first is the tendency of workers and entrepreneurs to hold their company's stock. The second is the propensity of workers to limit their equity holdings through...