Abstract: Agricultural machinery subsidy is an efficiency enhancement policy with threshold effect, in which efficiency and fairness can hardly be obtained simultaneously. This paper analyzes the impact of agricultural machinery subsidy on agricultural production and rural labor transfer through theoretical model. Further, it studies the income distribution effect and mechanism by instrumental variable method and mediator method. The results show that agricultural machinery subsidy significantly reduces the Gini coefficient of farmers' income and improves the fairness of income distribution. The mechanism is that agricultural machinery subsidy improves the agricultural production efficiency, promotes the rural labor transfer, and improves the income of migrant workers, especially the relatively poor farmers, thus offsetting the threshold effect and making the income distribution effect of agricultural machinery subsidy both efficient and fair.

Key words: agricultural machinery subsidy, threshold effect, spillover effect, rural labor transfer, income distribution effect

摘要： 农机补贴是具有门槛效应的效率增益政策，通常效率与公平如鱼和熊掌不可兼得。本文通过理论模型分析了农机补贴对农业生产及农村劳动力转移的影响；并通过工具变量法和中介变量法研究了农机补贴的收入分配效应及其作用机制。研究发现，农机补贴显著降低了农户收入的基尼系数，提高了收入分配公平性；其作用机制是农机补贴提升了农业生产效率，促进了农村劳动力转移，提高了打工收入，尤其是相对贫困农户，溢出效应对冲了门槛效应，使得农机补贴的收入分配效应兼具了效率和公平。

关键词: 农机补贴, 门槛效应, 溢出效应, 农村劳动力转移, 收入分配效应