公共选择理论中互投赞成票的逻辑与模型

The Logic and Model of Logrolling in Public Choice Theory

公共选择理论中互投赞成票模型的方法论基础是个体主义假设。作为一种方法论的个体主义与作为一种组织社会活动的规范的个人主义是两个根本不同的问题。在互投赞成票的论证逻辑中,包含了几个必要条件:一是必须采取多数表决规则;二是集体选择必须符合连续性假设,也就是说,集体选择是一个持续的独立决策流;三是少数派的偏好比多数派的偏好更为强烈,这暗含了偏好强度的差异性。根据这种逻辑,可以设计一个以公路修缮为主题的简单互投赞成票模型。这个模型的基本结论是:每个个体的理性行动导致了集体的非理性行动,集体的财政开支将超出合理的水平,其根本原因是多数表决规则的采用及由此造成的互投赞成票。通过概括和推广,这个简单互投赞成票模型可以应用于许多现实的集体决策情形中。

The methodological foundation of logrolling model in public choice theory is the individualism hypothesis. There are fundamental differences between the individualism as a methodology and the individualism as a norm for organizing social activities. There are several necessary factors in the logic of proving logrolling: first, it must contains majority vote rule; second, collective choice must be identified with continuity hypothesis, this is, collective choice is a stream of independent strategic decision-making; third, the preferences of minority are much stronger than that of majority, which implies the differences of preference strength. According to this logic, it is possible to design a simple logrolling model which is schemed by building roads. The basic conclusions of this model are: the rational activities of every individual will lead to the collective irrational activities; the collective expenditure will exceed reasonable level, and its root cause is the use of majority rule and its resulting logrolling. Through the generalization and its expanding use, the simple logrolling model can be used to many actual situations of collective strategic decision-making.