中文摘要
创业活动的税收待遇如何影响创办企业的决策？我们在波兰一项重大税制改革的背景下研究这一问题：该改革对企业主引入了单一税，而雇员的税收待遇保持不变。采用双重差分方法，并使用涵盖波兰全体纳税人的数据，我们发现，收入分布顶端的税率差异每增加1个百分点，改革五年后个体经营者占比便增加0.9%。这一增长主要由从受雇就业转向个体经营所驱动，尤其是单人个体经营（即不雇用从属劳动者的个体经营）。此外，这些转变发生在人力资本密集型行业。总体而言，我们发现高收入纳税人对个体经营吸引力提升作出了强烈反应，纷纷创办企业；这种行为表现出相当强的持续性，并随时间累积，且其中很大一部分可能反映的是收入重新分类，而非真正的创业活动。
Abstract
How does the tax treatment of entrepreneurial activity affect the decision to start a business? We study this question in the context of a major tax reform in Poland that introduced a flat tax for business owners, leaving the taxation of employees unchanged. Using a difference-in-differences approach and data on the universe of Polish taxpayers, we find that a 1 percentage point increase in the tax differential at the top of the income distribution leads to a 0.9% increase in the share of self-employed five years after the reform. The increase is primarily driven by transitions from employment to self-employment, in particular, solo self-employment (self-employment without dependent workers). Moreover, the transitions occur in industries with a high human-capital component. Altogether, we find that high-income taxpayers respond strongly to the increased attractiveness of self-employment by starting a business, that such behavior shows considerable persistence, that it accumulates over time, and much of it is likely to reflect income reclassification rather than genuine entrepreneurial activity.