Taiwan is experiencing a decline in the number of doctoral students in higher education. How to provide incentives for students to pursue a doctoral degree is a widely discussed issue. This paper constructs an occupational choice model with heterogeneous individuals in an overlapping generations model rationally choosing to study abroad, enter domestic doctoral programs, or work in industry. The framework captures the features of the two-stage Ph.D. labor market and the spillover effect of knowledge production on the industry sector. We also highlight the productivity differential between overseas-trained professors and their domestic counterparts. The model is used to quantify the effects of various subsidies on higher education. Our quantitative analysis suggests that providing a subsidy to domestic doctoral students is more effective in boosting the number of doctoral students than subsidizing professors' research. Nevertheless, in fields with a relatively large productivity differential, this policy does not necessarily improve average welfare because of fewer overseas-trained professors and lower knowledge accumulation.
台灣高等教育面臨博士生數量下降和教師高齡化現象,而如何吸引學生攻讀博士學位成為廣泛討論的議題。本文建構一個跨期疊代的職業選擇模型,模型中異質性個人理性地選擇出國攻讀博士、留在國內就讀博士、或進入產業工作。此架構能捕捉博士勞動市場的兩階段供需特徵,也可描繪知識生產對產業的外溢效果。此外,本文並將國內外博士學位間知識生產力的可能差異納入考慮。我們依此模型對各種高等教育補貼進行量化分析,結果顯示補貼國內博士生獎助學金比補貼教授的研究更能有效地增加博士生數量。然而,補貼國內博士生會造成出國攻讀博士學位的人數減少,而當國內外博士學位的知識生產力差異較大時,此政策不一定能增加國內知識累積與平均福利水準。