We consider the problem of portfolio selection within the classical Markowitz meanvariance framework, reformulated as a constrained least-squares regression problem. We propose to add to the objective function a penalty proportional to the sum of the absolute values of the portfolio weights....

Theoretical papers link the liquidity premium to the optimal trading decisions of investors facing transaction costs. In particular, investors' holding periods determine how transaction costs are amortized and priced in asset returns. Using a unique data set containing two million trades, this...