We study optimal nonlinear taxation of single and married households. Taxes on couples depend on the earnings of both spouses and are an example of multidimensional tax schedules. We develop novel analytical techniques to study properties of such taxes. We show that the optimal marginal taxes for married individuals are generally lower than for single individuals because resource sharing in couples provides socially valuable redistribution. Under realistic assumptions, the optimal tax rates for married individuals increase with the correlation of spousal earnings, the marginal tax rates for one spouse increase (decrease) in the earnings of the other if both spouses have low (high) earnings, and the primary earner faces lower marginal taxes than the secondary earner.

中文翻译：

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夫妻的最佳税收

我们研究单身家庭和已婚家庭的最佳非线性税收。夫妻税取决于配偶双方的收入，是多维税表的一个例子。我们开发了新颖的分析技术来研究此类税收的性质。我们表明，已婚个体的最佳边际税通常低于单身个体，因为夫妻资源共享提供了具有社会价值的再分配。在现实的假设下，已婚个人的最佳税率随着配偶收入的相关性而增加，如果配偶双方的收入都较低（高），则配偶一方的边际税率会增加（减少）另一方的收入，并且主要收入者面临的边际税低于次要收入者。