本文從Vernon (1966)的產品生命週期理論（the product cycle theory）著眼，來詮釋個別產業的空洞化。該理論描述產品經歷從新創、技術成熟、到生產標準化的階段，其生產地點隨產品生命階段之不同而持續移轉。對單一國家特定產業而言，其所生產的產品項目亦應不斷汰舊更新。當其產品更迭的速度減慢甚至停止時，代表其技術進步趨緩、生產活動減弱，就可能發生了產業空洞化。根據此一推論，本文修正應用Feenstra et al. (1999) CES出口函數模型指數分析法，觀察我國電子電器業在外人大量投資的1980年代與對外投資快速成長的1990年代，出口產品結構提升與產品更迭速度的變化，俾檢驗我國電子電器產業是否已出現空洞化。研究結果顯示，1990年代我國電子電器業在產品結構與更迭速度上並未惡化，在品質改善和產品更新速度上具有優勢的次產業（sub-industries）的比率與1980年代大致相同。但就整體產業觀察，1990年代產品品質雖仍持續提升，產品更新速度卻有減弱現象，值得注意。

This paper investigates whether the huge size of overseas direct investment of Taiwan's electric and electronics industry in the 1990s has caused its hollowing-out. According to Vernon's product life cycle theory, with the maturity of production technology, the production site of a product will move from where it is innovated, first to other developed countries, and then to developing countries. It also implies that the product content of an industry in a particular country will continue to change. If the product turmover of the industry slows down, it may indicate that hollowing-out has occurred. The product turmover index and the product mix index are computed for Taiwan's electric and electronics industry by applying the index model developed from a CES import function in Feenstra et al. (1999). The former is to measure the rate of entering new product areas in terms of dropping out of old products; and the latter is to measure the product structure change. We find that compared with product turnover in the 1980s, a period with large inward foreign direct investment, the hollowing-out effect does not seem to appear in the 1990s for the industry.