Portfolios for Long-Term Investors

How should long-term investors form portfolios in our time-varying, multifactor and friction-filled world? Two conceptual frameworks may help: looking directly at the stream of payments that a portfolio and payout policy can produce, and including a general equilibrium view of the markets’ economic purpose, and the nature of investors’ differences. These perspectives can rationalize some of investors’ behaviors, suggest substantial revisions to standard portfolio theory, and help us to apply portfolio theory in a way that is practically useful for investors.