台灣LED產業價值鏈、IPO時間與公司價值之研究

Abstract

過去文獻研究顯示公司IPO後短期與長期績效存在明顯的差異，而公司價值因產業別不同也會有明顯的變化。本文係研究我國LED產業價值鏈、公司IPO時間與股價淨值比間之關係。選取2001年至2007年間，在台灣證券交易所LED上市櫃公司為研究樣本，並按篩選標準選取，共533筆有效觀測樣本作為研究對象，包括上、中下游及相關應用企業共26家，運用迴歸分析法加以分析。研究內容中，首先將樣本資料依產業價值鏈及IPO時間分群，並將公司規模、股票指數報酬率、資產報酬率、負債比率、IPO時間及產業價值鏈為控制變數及預測變數，探討不同的產業價值鏈屬性及不同IPO時間長短與公司價值之間的關係。 本研究實證結果發現: 在台灣LED產業中，公司的產業價值鏈地位及IPO時間與股價淨值比呈顯著相關；IPO時間及產業價值鏈對於股價淨值比有交互作用關係存在。LED企業上市後，長期經營績效不一定比短期績效差，上游企業隨IPO時間的增長，股價淨值比明顯遞增，而中下游企業隨IPO時間的增長，股價淨值比緩慢遞減，這可能與台灣LED產業群聚網路發展及整合發揮綜效有關，也可能是該產業之上、中下游企業處於不同產品生命週期的階段，投資人給予不同評價。 從上面的結果發現，隨產業環境變化，其不同產業價值鏈地位之企業可能因經驗、技術累積而影響其公司價值，間接影響整個LED產業供應鏈的結盟發展。

Previous studies have shown there are substantial differences between short-run and long-run performances of firms in post-IPO. The value of the firms also undergoes obvious changes depending on their industries. This study examines the correlations between the Taiwanese LED industry, age of post-IPO, and P/B ratio of firms. The effective sample consists of 533 LED firms listed in the TWSE with regards to their IPO between 2001 and 2007. Twenty-six firms along the industry value chain are then evaluated using regression analysis. In the first step of this study the samples were categorized according to their industry value chain and age of post-IPO. In the second step P/B ratio was used as the dependent variable, and evaluated against various independent variables, including: firm size, stock index return, return on asset (ROA), debt ratio, age of post-IPO, and industry value chain as the independent variables. The empirical results of this study are as follows: 1) In the Taiwanese LED industry, a firm’s position in the industry value chain, and the age of post-IPO have joint effects on the P/B ratio. 2) The long-run performance is not always worse than the short-run performance after the LED firm’s IPO. The performance depends on the firm’s position in the industry value chain. For upstream firms, P/B ratio will increase significantly along with the increasing age of post-IPO. For mid and downstream firms, P/B ratio decreases slowly as time passes with the IPO. These characteristics could be related to the integration and synergy of industry clusters, or as the result of different evaluations by investors towards different products along the value chain at different stages of the product life cycle. The results indicate that the accumulation of experience and skills directly influence the firm’s value depending on their role in the value chain, and indirectly influence the development of the entire LED value chain.