Economic theory suggests that market economies are likely to underprovide innovation because of the public good nature of knowledge. Empirical evidence from the United States and other advanced economies supports this idea. We summarize the pros and cons of different policy instruments for promoting innovation and provide a basic "toolkit" describing which policies are most effective according to our reading of the evidence. In the short run, R&D tax credits and direct public funding seem the most productive, but in the longer run, increasing the supply of human capital (for example, relaxing immigration rules or expanding university STEM admissions) is likely more effective.

中文翻译：

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促进创新的政策工具包

经济学理论认为，由于知识的公共善性，市场经济可能无法充分提供创新。美国和其他发达经济体的经验证据支持这一观点。我们总结了促进创新的不同政策工具的利弊，并提供了基本的“工具包”，根据我们对证据的了解，描述了哪些政策最有效。在短期内，研发税收抵免和直接公共资金似乎最有成效，但从长远来看，增加人力资本的供应（例如放宽移民规定或扩大大学STEM入学率）可能更有效。