Article Contents
Article Contents

# 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 with a rational investor, an optimistic irrational investor tends to consume more, while a pessimistic irrational investor tends to consume less. Second, the more irrational the investor, the more volatile his consumption. Third, the extremely irrational investor can get more ex ante expected utility than his rational counterpart, no matter he is optimistic or pessimistic.
Mathematics Subject Classification: Primary: 91B28; Secondary: 91B08, 91B16, 91B70.

 Citation:

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