臺灣資訊電子業供應網絡之垂直資訊移轉

Abstract

投資者藉由觀察一家公司發布之資訊，預測其他公司未來之經營成果與現金流量，使兩公司之股價產生關聯即為資訊移轉效果。過去國內、外研究均顯示，產業內具有水平之資訊移轉效果，且具有直接供需關係之上、下游廠商或上、下游產業亦具有垂直資訊移轉效果。環顧國內、外文獻，多階層之供應網絡垂直資訊移轉尚無人研究。同產業供應網絡內之廠商彼此皆具有直接或間接之供需關係，因此投資者可能透過觀察下游公司發布之資訊，預測上游公司未來經營成果暨現金流量，使兩公司股價產生關聯，發生垂直資訊移轉效果。資訊電子產業素來具有技術密集之特性，其要求技術專精導致細膩專業之分工，因此具有綿密的供應網絡，故本研究針對資訊電子產業供應網絡探討垂直資訊移轉效果是否存在。 本研究以民國九十六年四月至民國九十七年三月間資訊電子產業供應網絡最下游領導公司發布之月營收資訊，觀察該公司與供應網絡上游之上市、櫃公司是否具有垂直資訊移轉效果，且該效果是否會隨著供需關係改變方向與大小。同時本研究亦探討垂直資訊移轉效果是否具有稀釋性，即上游公司與下游發布公司之距離是否會對垂直資訊移轉效果產生影響。最後亦探討供應網絡內上游與下游發布公司連結緊密程度對垂直資訊移轉效果之影響。 實證結果發現資訊電子產業供應網絡內具有垂直之資訊移轉效果，且方向與大小隨公司間供需關係而定。本研究亦發現資訊電子產業供應網絡內垂直資訊移轉效果具有稀釋性，當上游公司與下游發布公司距離越遠，垂直資訊移轉效果越小。而本研究未發現上游與下游發布公司連結緊密程度會影響垂直資訊移轉效果之證據。

Information transfer means that information disclosed by one firm can have effect on the stock prices of other related firms. Prior studies found intra-industry horizontal information transfer and vertical information transfer between retailer and suppliers. In an industry, up-stream firms supply goods to down-stream firms, thus creating a supply network. The announcements of operation results by down-stream firms may provide information that investors can use to revise their assessments of the up-stream firms’ future operating results and cash flows. Therefore, the stock prices of the up-stream firms may change as a result of the announcements. The characteristics of complicated technology in the information electronics industry causes division of labor, hence the information electronics industry has a lengthy supply network. This paper investigates the extent of intra-industry vertical information transfers associated with the monthly sales announcements of a sample of Taiwan’s information electronics companies. We assess vertical information transfers and their degree by examining the association between the monthly sales announcements of down-stream announcing firms and up-stream firms. Also we investigate the distance dilution effect of vertical information transfers. Last, we assess the effect of connection degree between down-stream announcing firm and up-stream firms. We find vertical information transfers do exist in the information electronics industry, and the amount of information about depends on the supply and demand relationship between firms. We also find that the longer distance between the announcing firm and up-stream firms, the weaker the vertical information transfer effect. However, we do not find the effect of connection degree on vertical information transfers.