臺灣蘋果進口需求體系之估計

Modeling Import Demand for Apple in Taiwan

蘋果為臺灣重要的進口農產品。本文以一階差分近似理想需求模型估計臺灣在入會世界貿易組織前後、全球金融危機發生後、臺紐經濟合作協定生效後及COVID-19疫情後之美國、智利、日本、紐西蘭及其他國家（五國加總）的蘋果進口需求彈性。估計結果顯示日本蘋果及美國蘋果之進口需求彈性幾乎沒有結構性的轉變。日本蘋果長期呈現高單價。美國長期為臺灣所有蘋果進口份額最大的進口國，且與智利、日本等其他進口來源國的蘋果為互補關係。長期來講美國、智利及日本進口蘋果的自我價格彈性符合農產品之價格敏感度不高的特性。然而，臺灣消費者普遍對於各國進口蘋果的價格變化逐漸不具彈性，尤其對於智利蘋果的價格敏感度逐年降低。另外，本文發現入會世界貿易組織前後及簽訂臺紐經濟合作協定後容易造成蘋果進口需求體系的結構性轉變，尤其蘋果進口國間的互補關係明顯出現。另外，臺灣消費者的支出彈性在發生全球金融危機前較高，進口蘋果屬於奢侈財，而發生全球金融危機後支出彈性開始降低甚至小於1（約0.7），臺灣消費者的偏好逐漸將進口蘋果視為正常財。

Apple is a crucial agricultural import in Taiwan. This study applied a dynamic AIDS model to estimate the demand elasticity of apple imports from the USA, Chile, Japan, and New Zealand after three events. (i.e., the WTO members of Taiwan, the GFC, the NZTEC, and the COVID-19 pandemic). The results show nearly no structural change in elasticity for Japanese apples and USA apples. In the long run, the unit price of Japanese apples is relatively high, and the share of the USA is the largest. In addition, there is a complementary relationship between the USA and other apple importers. In general, the price elasticity of the USA, Chile, and Japan is consistent with the rule of lower price sensitivity of agricultural products. However, the price elasticity of imported apples gradually decreased, especially those from Chile. In addition, regional trade agreements (i.e., the WTO membership of Taiwan and the ANZTEC) are more likely to cause structural changes. The complementary relationship between apple importers is likely found later.