解除市場管制的社會福利效果：疊代模型的分析

The Social Welfare Effect of Deregulation in the Goods Market: Analysis of an Overlapping-Generations Model

已有許多文獻探討解除市場管制對社會福利的影響，大多文獻都支持解除市場管制可以提高代表性個人的福利，可惜的是並沒有文獻在疊代模型中探討這個問題。本文在疊代模型中考慮獨佔性競爭的設定，得到以下幾點結論：（1）解除市場管制確實能提升年輕世代的福利、但卻會降低年長世代的福利；（2）疊代模型中，將所有世代的福利加總，無論是否考慮未來世代的福利，解除市場管制都能夠提高整體社會的福利；（3）僅考慮既存世代的福利之下，疊代模型中解除市場管制所能提升的整體福利不及代表性個人模型；（4）同時考慮既存世代與未來世代的福利時，疊代模型中解除市場管制所能提升的整體福利超過代表性個人模型；（5）疊代模型中，出生與死亡的機率越大，因市場管制而受害的人口比例將越低。 The recent economic literature argues that deregulation in the goods market has beneficial impacts on social welfare and that full deregulation is optimal for the infinitely-lived agent, yet no study has tried to estimate the welfare effect of deregulation in the model with new generations. This paper considers the degree of monopoly in an overlapping-generations model and offers the following conclusions. (1) Deregulation in the goods market is harmful to older generations, but is beneficial for younger generations. (2) Deregulation in the goods market raises total social welfare regardless of which future generations exist in the overlapping-generations model. (3)The welfare benefit of deregulation for the infinitely-lived agent is larger compared the overlapping-generations model that only contains current generations. (4) The welfare benefit of deregulation for the infinitely-lived agent is smaller than that in the overlapping-generations model that has future and current generations. (5) The higher the death and birth rates are, the lower the proportion is of the population harmed by regulation in the overlappinggenerations model.