Bequest and Wealth Accumulation: Are Some Pieces of the Puzzle Missing?
评论Kotlikoff与Modigliani关于储蓄动机的争论，分析退休储蓄、预防性储蓄和计划遗赠对财富积累的贡献，并澄清估算差异，引入国际证据。
The lively debate between Laurence J. Kotlikoff and Franco Modigliani presented in the Spring 1988 issue of this journal concerns an old question: what is the main motivation for saving and therefore for the accumulation of wealth? More specifically, what are the respective contributions to aggregate wealth of 1) saving for retirement (also known as “hump” saving); 2) precautionary savings (and “unintended” bequests) due to uncertainty about the length of life; and 3) planned bequests? If Modigliani's life-cycle hypothesis is to be viewed as a close to approximation of reality, then the bulk of existing wealth should have resulted from some combination of hump and precautionary saving. Our comment on this dispute attempts to advance two issues. First, the controversy involves an enormous gap between empirical estimates of the share of “inherited wealth” in total accumulation, even though the estimates are often based on the same data. We hope to clarify why the estimates vary so widely. Second, the Kotlikoff/Modigliani dispute is presented as an American issue, with little extension abroad. We will present some results from other countries that bear on the controversy.