OPTIMAL MIGRATION: A WORLD PERSPECTIVE*
研究在加权全球福利最大化目标下，最优移民规模远高于当前水平，除非对富裕国家居民给予极高权重。
We ask what level of migration would maximize world welfare. Welfare is assumed to be a weighted average of the utilities of the world’s various citizens, but the weights are also country specific. Using a calibrated one‐sector model, we find that unless the weights are heavily biased toward the natives of rich countries, the extent of migration that would be optimal far exceeds the levels observed today. The claim remains true in a two‐sector extension of the model. All versions of the model assume that migration is the only redistributive tool.