本文以編算IC 產業上、中、下游各股價指數的方式，探討其間垂直分工特性之關聯性。 研究發現：IC 上、中、下游產業，長期間不具有穩定均衡關係。短期間，IC 設計及IC 封裝產業受到所有產業的影響，唯IC 製造業在短期內僅受其本身的影響。由因果檢定得 知，IC 上、中、下游三產業間並不具有任何領先－落後之關係。在衝擊反應分析中，IC 製造業的突發性衝擊，除了對其本身有較顯著且持續性的反應外，亦對其餘變數呈現越 來越顯著且延續長時期的正面影響，顯示出其最具影響力的角色。最後在變異數分解中 發現，IC 製造業外生性最強，對自身變異的解釋能力高，受其他IC 產業的影響程度相當 低，而IC 設計業及IC 封裝業發生變異時，受IC 製造業的解釋極強，且隨著期數的增加 而顯著提高，說明了IC 製造業之變動，在整體IC 產業中扮演著一個相當重要的要角； 換言之，IC 製造業足以做為其他IC 產業的變動指標。

The purpose of this study is to examine the interrelationships among the stock indexes of the upper, middle and lower stream of IC industry in Taiwan by using time series method. The results found that there is no long-term equilibrium relationship among the upper, middle and lower stream of IC industry in Taiwan. In the short-term, IC design and IC packaging industries have been influenced by all industries except manufacturing industry. From the causality test, there are no lead-lag relationship among the IC design, packaging and manufacturing industries. The empirical results of impulse response functions and variance decompositions point out that, comparing those IC industries, there is stronger sudden impulse to the exogenous in IC manufacturing industry. On the other hand, there are less and shorter impact of the exogenous disturbance in IC design and packaging industries.

IC 產業; 時間序列; 股價指數

IC industry; Time series; Stock index