离散因变量模型

去

离散因变量模型

一，选择集：

1，选择的对象不能重迭，必须相互可以排除掉对方。选择一样，其他的就不能选。不能同时选两个。

2，选择集要全。至少要选一个。

3，选择的个数是有限个。

以上三条可概括为：不漏，不重，不空。

The first and second criteria are not restrictive. Appropriate definition

of alternatives can nearly always assure that the alternatives are mutually

exclusive and the choice set is exhaustive. For example, suppose two

alternatives labeled A and B are not mutually exclusive because the

decision maker can choose both of the alternatives. The alternatives can

be redefined to be “A only,” “B only,” and “both A and B,” which are

necessarily mutually exclusive. Similarly, a set of alternatives might not

be exhaustive because the decision maker has the option of not choosing

any of them. In this case, an extra alternative can be defined as “none

of the other alternatives.” The expanded choice set, consisting of the

original alternatives plus this new one, is clearly exhaustive.