Optimal consumption and investment under irrational beliefs

In this paper, we study how irrationality affects the investor's consumption and investment decisions. We build a continuous-time financial model,where an irrational investor determines his consumption and investment according to an exogenous price process. The main results are as follows. First, compared witha rational investor, an optimistic irrational investor tends to consume more, while a pessimistic irrational investor tends to consume less. Second, the more irrationalthe investor, the more volatile his consumption. Third, the extremely irrational investor can get more ex ante expected utility than his rational counterpart, no matter heis optimistic or pessimistic.