本研究以Fama-French(1993)所提出的三因子模型及Carhart(1997)四因子模型為基礎,將其改寫為PSTR架構,並以投資者情緒代理變數-券資比作為轉換變數,評估股價報酬的非線性動態效果:四個依時變動的風險溢酬,以及券資比對股價報酬所產生的門檻效果。實證期間為2008年第1季至2015年第2季,實證對象為台灣50之成分股, 在扣除金融股及資料不足之公司後,計有34家公司。 實證結果顯示: 一、小規模公司較大規模公司具有超額報酬;成長型的公司較價值型的公司具有超額報酬。 二、四個風險溢酬均是顯著異於零,且隨個別公司在不同時間的券資比而變動,而非傳統三因子或四因子模型所主張的「固定值」。 三、當公司股票的券資比處於很高的水準時,投資規模小及高成長的公司更具有額外報酬;在公司股票的券資比處於中度水準時,投資價值型及法人持股比率未偏高的股票更具有額外報酬。
This thesis rewrite the four-factor model, developed by Carhart(1997), as a panel smooth transition regression(PSTR) framework, and uses margin balance/ financing balance ratio as the transition variable in the framework, to evaluate the nonlinear path of stock returns and four time-varying risk premiums. Sample period span from 2008:Q1 to 2015:Q2. Sample objects are 34 companies listed on FTSE TWSE Taiwan 50 Index. The empirical results can be summarized as follows: 1.Holding growth stocks can lead to higher returns than the value; holding small size stocks can lead to excess returns than big size. 2.In the PSTR model, four risk premiums vary with time and across stocks, depending margin balance/ financing balance ratio in different regimes, not constant obtained from the traditional three-factor model and four-factor model. 3.When the company stock’s margin balance/ financing balance ratio is at a high level, owned small size and growth stocks can lead to excess returns; when the ratio is at a medium level, owned value stocks and corporate ownership ratio isn’t high can lead to excess returns.