本文使用2000年至2016年的UN Comtrade電腦產品進口資料來推估電腦產品品質指數。由於電腦產品品質與電腦產品價格會有內生性問題，因此本文利用兩階段最小平方法估計電腦產品之需求函數，得出電腦產品之品質指數。實證發現中國出口至非洲及大洋洲之電腦產品品質有增加的趨勢，本文進一步將電腦產品出口量考慮進來後，發現中國在電腦產品加權品質上被日本超越。其後本文定義出不同類型出口產品，發現在中國持續出口產品品質表現最好，退出出口產品品質表現最差；而日本的各個出口類型沒有顯著差異。而本文也計算不同出口類型對電腦產品品質成長率的貢獻，並發現持續出口類型的貢獻最大。

This paper aims to estimate the computer products’ quality index, applying the import data of computer products from UN Comtrade for the period 2000 to 2016. Due to the problem of endogeneity, we use the two-stage least squares method to estimate the demand function. The residuals of the estimated demand function are constructed as the quality index. We find that the quality of computer products exporting from China to Africa and Oceania increases over time. Besides, the weighted average quality index of Japan surpass the weighted average quality index of China.
We also find that, for China’s computer products, the quality of continuing exporting goods is the highest, while the quality of the goods that exit the destination countries is the lowest. For Japan’s computer products, there is no significant difference between the types of export.
At last, we calculated the contributions of different types of exporting goods to the quality growth of computer products, and we find that continuing exporting goods contributes the most.

1. 李浩仲與翁培真 (2015), “台灣出口產品品質的演進”,《經濟論文叢刊》, 43, 1-51。
2. 楊子菡與廖月波 (2004), “產品生命週期與產業空洞化―臺灣電子電器業之實證研究”,《臺灣經濟預測與政策》, 35, 67-89。
3. 蔡東杰 (2004), “東亞雁行結構的調整與變遷”,《全球政治評論》, 7, 1-18。
4. 陳宏易與黃登興 (2009), “亞洲地區產業競爭優勢的更迭:雁型理論的再驗證”,
《經濟論文叢刊》, 37, 185-211。
5. 林培州 (2003), “台灣製造業廠商進出市場與產業生產力之成長分析”, 《經濟論文叢刊》, 31, 279-319。
6. Schott, P. K. (2004), “Across-Product Versus Within-Product Specialization In International Trade”, The Quarterly Journal of Economics, 119, 647-648.
7. Hummels, D. & Klenow, P. J. (2005), “The Variety and Quality of a Nation’s Exports”, American Economic Review, 95, 704-723.
8. Jarreau, J. & Poncet, S. (2012), “ Export Sophistication and Economic Growth: Evidence from China”, Journal of Development Economics, 97, 281-292.
9. Hallak, J. C. & Schott, P. K. (2011), “Estimating Cross-Country Differences In Product Quality”, The Quarterly Journal of Economics, 126, 417-474.
10. Hallak, J. C. & Sivadasan, J. (2013), “Implications for quality choice and conditional exporter premia”, Journal of International Economics, 91, 53-67.
11. Crozet, M., Head, K. & Mayer, T. (2012), “Quality Sorting and Trade: Firm-level Evidence for French Wine”, Review of Economic Studies, 79, 609-644.
12. Mazzeo, M. J. (2002), “Product choice and oligopoly market structure”, The Rand Journal of Economic, 33, 221-242.
13. Berry, S. T. (1994), “Estimating Discrete-Choice Models of Product Differentiation”, The Rand Journal of Economic, Vol. 25, No. 2, 242-262.
14. Khandelwal, A. (2010), “The Long and Short (of) Quality Ladders”, Review of Economic Studies, 77, 1450-1476.
15. Pula, G. & Santabárbara, D. (2012), “Is China UP Climbing Up The Quality Ladder? ”, No 1310, Working Paper Series from European Central Bank.
16. Feenstra, R. C. (1994), “New Product Variaties and the Measurement of International Prices”, The American Economic Association, Vol. 84, No. 1, 157-177.
17. Disney, R., Haskel, J. & Heden, Y. (2000), “Restructuring and Productivity Growth in UK Manufacturing”
18. Foster, L., Haltiwanger, J. C. & Krizan, C. J. (2001), “Aggregate Productivity Growth. Lessons from Microeconomic Evidence”, National Bureau of Economic Research, 303-372.
19. Law, D. & McLellan, N. (2005), “The Contribution from Firm Entry, Exit and Continuation to Labor Productivity Growth in New Zealand”, New Zealand Treasury Working Paper, No. 05/01.
20. Broda, C., & Weinstein, D. E. (2006), “Globalization and the Gains from Variety”, The Quarterly journal of economics, 121(2), 541-585.