Classic decision theory asserts that decision makers should choose the option that offers the highest expected value. Daniel Bernoulli [24] (Trepel, Fox and Poldrack, 2005) suggested that people do not evaluate options by their objective value but rather by their utility and conjectured that appropriate choices are those for which the expected utility is maximum. Bernoulli also argued that utility functions should to be a concave function because he assumed that the marginal utility decreases as the assets increases.