Preferências assimétricas em decisões de investimento no Brasil

• Ano de defesa: 2008
• Autor(a) principal: Martits, Luiz Augusto
• Orientador(a): Eid Júnior, William
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Palavras-chave em Português: Mercado acionário brasileiro; Aversão a perdas; Teoria da perspectiva; Portfólio ótimo de investimentos; Maximização da utilidade
• Palavras-chave em Inglês: Utility maximization; Loss aversion; Brazilian stock market; Optimum investment portfolio; Prospect theory
• Link de acesso: http://hdl.handle.net/10438/2580

The main objective of this thesis is to test the hypothesis that utility preferences that incorporate asymmetric reactions between gains and losses generate better results, when applied to the Brazilian market, than the classic Von Neumann-Morgenstern expected utility function. The asymmetric behavior can be computed through the introduction of a disappointment (or loss) aversion coefficient in the classical expected utility function, which increases the impact of losses against gains. This kind of adjustment is supported by recent developments in financial theory, specially those studies that try to solve the violations of the expected utility axioms. The analysis of the implications of such adjustment is made through the comparison of the results regarding the participation of the risky asset (stock market) in the composition of the optimum portfolio (the one that maximizes utility) generated by both types of preferences: expected utility and loss aversion utility functions. The results are then compared with real data from two types of Brazilian investors (pension funds and households) aiming at verifying the capacity of each utility function to replicate real investment data from these investors. The results of the tests show that it is not possible to reject the expected utility function as an adequate representative model for the aggregate behavior of Brazilian pension funds. However, the simulations indicate that this type of function should be rejected as an adequate model to replicate real investment decisions of Brazilian individual investors (households). The behavior of this type of investors can be better replicated by applying a loss aversion utility function.