SOCIAL SECURITY AND RETIREMENT DECISION: A POSITIVE AND NORMATIVE APPROACH*
分析社会保障制度导致提前退休的现象，指出虽然许多国家存在过度提前退休的偏差，但完全消除这一偏差（转向精算公平制度）并非正确选择，因为部分扭曲是次优最优，且从政治角度看可能不可行或削弱对养老金制度的支持。
Abstract Social insurance for the elderly is judged responsible for the widely observed trend towards early retirement. In a world of laissez‐faire or in a first‐best setting, there would be no such trend. However, when first‐best instruments are not available, because health and productivity are not observable, the optimal social insurance policy may imply a distortion on the retirement decision. The main point we make is that while there is no doubt that retirement systems induce an excessive bias towards early retirement in many countries, a complete elimination of this bias (i.e. a switch to an actuarially fair system) is not the right answer for two reasons. First, some distortions are second‐best optimal. This is the normative argument. Second, and on the positive side, the elimination of the bias might be problematic from a political perspective. Depending on the political process, either it may not be feasible or alternatively it may tend to undermine the political support for the pension system itself.