Abstract In this paper we ask the following question: Is the optimal Earned Income Tax Credit (EITC) schedule a trapezoid, as widely used by policy-makers, or is it a triangle? We show that a trapezoid is optimal only when the wage distribution among the working poor is even with a discrete jump for higher wage groups. Since this pattern is not in line with the observed wage distributions of countries, we conclude that the optimal schedule is a triangle. Our simulations show that the use of a trapezoid implies a substantial loss in terms of Social Welfare.

中文翻译：

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最佳收入所得税抵免 (EITC) 计划：梯形还是三角形？

摘要 在本文中，我们提出以下问题：最优收入所得税抵免 (EITC) 计划是决策者广泛使用的梯形还是三角形？我们表明，只有当工作穷人的工资分配与较高工资组的离散跳跃一致时，梯形才是最佳的。由于这种模式与观察到的国家工资分布不符，我们得出最佳时间表是三角形的结论。我们的模拟表明，梯形的使用意味着社会福利方面的重大损失。