疊代研發模型中的最適補貼政策

THE OPTIMAL SUBSIDY POLICIES IN THE OVERLAPPING GENERATIONS MODEL WITH R&D

在研究發展Research and Development（R&D）的成長模型中，創新成功者以專利與商標的形式獲得獨占權，導致商品的售價大幅高於邊際成本，並使得商品的需求量大幅低於最適水準，進而帶來社會福利的損失。既存文獻在代表性個人的非疊代模型中，比較了各種補貼政策矯正社會福利損失的能力。而疊代的總體模型中，各世代持有的資產數目不同，政府的補貼措施會對各世代的財富造成不同的影響，形成跨代財富重新分配的現象。因此，本文採用世代交替的疊代模型作為分析的架構，比較利息補貼、最終財補貼、中間財補貼與研發補貼等四種補貼政策，而不同的補貼政策將形成不同的跨代財富重分配效果，進而對經濟成長與社會福利造成不同的影響。

In the Research and Development (R&D) model of economic growth, monopoly rights are granted to successful innovators in such forms as patents and trademarks. With monopoly protection, pricing rises high above marginal costs, and the demand for goods is far below the optimal level, finally, resulting in deadweight loss. With infinitely-lived representative households in non-overlapping-generation models, various studies have com-pared several subsidy policies to correct the distortion of the monopoly pricing. On the other hand, in overlapping-generation models, since the assets of generations differ, subsidy policies transfer the wealth among the generations, forming intergenerational wealth redistribution. Therefore, this paper addresses several subsidy policies in an overlapping-generation model, including subsidizing interest income, final output, intermediate goods, and R&D to further explore whether the effects of subsidy policies on economic growth and social welfare depend significantly on the subsidy policies giving rise to the intergenerational wealth redistribution.