  As we know, there is a controversy about the decision making under risk
between economists and psychologists. We discuss to build a unified theory of
risky choice, which would explain both of compensatory and non-compensatory
theories. For risky choice, according to cognition ability, we argue that
people could not build a continuous and accurate subjective probability world,
but several order concepts, such as small, middle and large probability. People
make decisions based on information, experience, imagination and other things.
All of these things are so huge that people have to prepare some strategies.
That is, people have different strategies when facing to different situations.
The distributions of these things have different decision structures. More
precisely, decision making is a process of simplifying the decision structure.
However, the process of decision structure simplifying is not stuck in a rut,
but through different path when facing problems repeatedly. It is why
preference reversal always happens when making decisions. The most efficient
way to simplify the decision structure is calculating expected value or making
decisions based on one or two dimensions. We also argue that the deliberation
time at least has four parts, which are consist of substitution time, first
order time, second order time and calculation time. Decision structure also can
simply explain the phenomenon of paradoxes and anomalies. JEL Codes: C10, D03,
D81
