Sénéchal proposes a new analytical framework—the empirical law of active management—to assess the breadth, or diversification, and the skill of a portfolio manager. The framework requires no assumptions regarding a manager’s asset return expectations or investment process. The framework...

Using a large sample of institutional investors' investments in private equity funds raised between 1991 and 2011, we estimate the extent to which investors' skill affects their returns. Bootstrap analyses show that the variance of actual performance is higher than would be expected by chance,...