Utilitarianism, Egalitarianism, and the Timing Effect in Social Choice Problems
推导了两个关于社会选择函数的定理，表明线性条件与帕累托最优结合导致功利主义，而凹性条件与帕累托最优及无关选项独立性结合则导致功利主义或平等主义，并解释了这些条件在不确定性解决前后对社会福利分析的影响。
Two theorems are derived about social choice functions, which are defined on comprehensive convex subsets of utility allocation space. Theorem 1 asserts that a linearity condition, together with Pareto optimality, implies that a social choice function must be utilitarian. Theorem 2 asserts that a concavity condition, together with Pareto optimality and independence of irrelevant alternatives, implies that a social choice function must be either utilitarian or egalitarian. These linearity and concavity conditions have natural interpretations in terms of the timing of social welfare analysis (before or after the resolution of uncertainties) and its impact on social choices.