Productivity Growth and Structural Change in an Economy with Capital Accumulation

本文建構一兩部門新古典成長模型，並用以分析經濟成長中，生產要素的結構變遷。在經濟成長的過程中，勞動與資本等生產要素大量移出農業部門，並轉而投入非農業部門。本文的分析指出，當農業部門的生產力提升，農業部門會有多餘的勞動力與資本溢出，並將生產要素推向非農業生產部門。而非農業部門的生產力提高，會帶動兩部門的資本累積，由於資本與勞動的互補性，資本累積較快的部門將吸引較多勞動力。如果非農業部門的資本彈性較高，勞動和資本將會被拉向非農業部門。本文進一步利用此模型結合美國資料進行數量分析，發現在美國 1869—2011 年間的結構變遷中，農業生產力的「推力」以及非農業生產力的「拉力」都扮演了相當重要的角色，缺一不可。本文最後也應用此模型，討論潛在的資源錯置，並分析可能延緩或加速結構變遷的政策。This paper develops a two-sector neoclassical growth model to study structural transformation where labor and capital are reallocated out of agriculture. We find that advances in farming technology create a spillover of resources, pushing labor and capital out of agriculture. Non-agricultural productivity growth leads to capital formation in both sectors, and capital attracts labor due to complementarity. The agriculture share of labor and capital declines when capital is more elastic in the non-farm sector. Our quantitative analysis shows that productivity growth in both farm and non-farm sectors contributed significantly during the U.S. structural trans- formation for the period 1869–2011. We then extend the model to explore potential distortions and policies that may retard or fuel the transition