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Expected utility theory is in the 1950s, Von Neumann and Morgenstein (von Neumann? And Morgenstern) based on axiomatic assumptions, a framework for analyzing the choice of rational actors under uncertain conditions is established by using logic and mathematical tools.

However, this theory combines individuals and groups into one. Later, Arrow and Debrou absorbed it into the framework of Walras equilibrium, which became an analytical paradigm to deal with uncertain decision-making problems, and then built a grand and beautiful theoretical building of modern microeconomics, including macroeconomics, finance and econometrics.

Modified extension of expected utility function theory;

1 and Karmark( 1978) put forward the concept of subjective weighted utility (SWU). Replacing linear probability with decision weight can explain Correze problem and * * * year-on-year effect, but it cannot explain the violation of dominance principle.

2. Generalized utility model. The characteristic of this kind of model is that for the same result effect and the same ratio effect, the linear characteristics of expected utility function are relaxed or axiomatic assumptions are restated, and the model will use the indifference curve of linear characteristics of expected utility function represented by probability triangle.

3. Introduce the concept of "regret" to explain the non-transitivity of year-on-year effect and preference; For example, the "regret model" proposed by Loomes and Sudgen( 1982) introduces a regret function, which lays the utility on the individual's psychological experience of the past "not choosing" results.