Discrete Portfolio Adjustment with Fixed Transaction Costs

Abstract

This paper presents a closed form solution to the portfolio adjustment problem in discrete time when the investor faces fixed transaction costs. This transaction cost model assumes a mean-variance investor who wants to adjust her holdings of a risky and risk-free asset. It is shown how this model can be calibrated to be used with a variety of risk models such as life cycle portfolio weights and value at risk (VaR) models. The decision problem can easily be inputted into and calculated in Excel.

Keywords: adjustment costs, alpha models, brokerage commissions, fixed costs, lifecycle funds, portfolio selection, portfolio theory, risk management, transaction costs, Value at Risk (VaR)

JEL Classification: G11