本文主要探討影響券商分析師所發布的研究報告目標價預測誤差的因素，以及了解券商目標價預測誤差是否會在不同的情況下有所不同，如券商國籍、分析產業。本文研究期間為2008年至2014年，目標價預測總共有效樣本有39,585筆，資料來源為CMoney，其中外資券商發布百分比共有30.16%，本土券商發布百分比有69.84%。電子業占總樣本百分比有63.21%，非電子業占總樣本百分比有36.79%。從分析師發布研究報告的趨勢來看，分析師把較多的資源以及心力在台灣電子業，因此本文亦想了解台灣分析師對於電子業的目標價預測能力使否顯著優於非電子業。此外，1998年全球大型投資銀行及專業券商因台股成交量日益龐大，大舉進入台灣市場，而外資券商所發布的研究報告，主要提供給三大法人，其買賣動向往往是市場中的焦點，因此外資券商目標價預測是否有比本土券商來的高，也是一門有趣的課題值得我們在本文探討。 本文利用Bonini et al.(2010)方法並加以修正，重新定義目標價預測誤差，差別在於本文所探討的目標價預測誤差為根據分析師所發布目標價，在一定的投資期間內與真實股價最接近的時點的誤差程度。最後從實證結果發現以下幾點結論：(一) 目標價的時效性在超過發布三個月後逐漸消失；(二) 電子業的目標價預測誤差大於非電子業；(三) 外資券商分析師目標價預測誤差大於本土券商；(四) 外資持股比重越高，會使目標價預測誤差縮小；(五) 動能表現會影響到分析師的目標價之判斷，且二者呈反向關係。

經濟預測一直是學界所非常重視的問題，舉凡失業率、消費者物價指數、貨幣供給量等等，都存在著某種程度的預測力。而本篇研究所探討的預測指標為違約利差。這個指標自1983年被Bernanke所提出來後，諸多學者在此概念下對其定義做改造，像是商業本票與國庫券間的利率差、Baa評級債券與國庫券之利率差、高殖利率債券與國庫券之利率差都屬於違約利差的一種。而我們這篇使用twA評級六個月期債券與六個月期國庫券之利率差和六個月期商業本票與六個月期國庫券間利率差去預測經濟成長率，我們發現此預測力並不彰顯。探究其原因可能是twA評級六個月期債券與六個月期國庫券之利率差變數不只包含了與經濟活動有關的違約風險部分，還包含了流動性風險、預付風險、稅務貼水、營運系統性風險等等。而商業本票與國庫券間利率無預測力的原因可能是金融替代品的增加、投資者對市場感知不正確或國庫券供需量可能會因政策施行(非景氣相關之政策)而變動所造成。最後我們將所有台灣的預測變數的預測值做簡單平均，再算出平均平方誤差。我們發現預測能力相較於自我迴歸模型來得差，但這相比於其他單一變數預測式所估計出來的預測誤差來得穩定。本研究中未能像Stock and Watson般使用上百條式子再做加權，因此這可能會是加權平均在台灣市場的例子中，預測能力輸給自我迴歸模型的主因。

本文應用向量自我迴歸模型與一般化預測誤差變異數分解，並將其估計結果導入網路拓樸與引力佈局模型的概念，來探討臺灣類股與國際股票市場之間報酬率的傳導結構與外溢效果。我們使用了 2001 年 7 月至 2015 年 10 月的臺灣加權股價指數、臺灣 19 個類股股價指數與國際間 43 個國家之主要股市指數來進行分析。我們發現，除了已開發國家之股市對臺灣類股有較大的影響外，部份亞洲發展中國家亦與臺灣類股之間有相當緊密的連結。另外，雖然國際股市對臺灣類股的外溢效果在 2013 年之後有所下降，但整體而言，臺灣類股受到國際股市的影響在過去十年之間大致呈現上升的趨勢。

本文旨在檢視股東會年報之資訊揭露是否具有預測價值，分別以年報資訊數量及品質二者與分析師盈餘預測誤差及分歧程度之關係探討之。研究結果顯示，年報揭露之資訊數量與資訊品質愈高，分析師盈餘預測誤差愈低，足見我國年報內容有助於提升分析師預測準確度。就年報揭露程度與分析師盈餘預測分歧程度之關聯性而言，本研究發現，年報資訊揭露數量愈多，分析師預測分歧性愈低；然本研究並未能證實，年報資訊揭露品質與分析師預測分歧性具有顯著的反向關係。換言之，資訊數量與預測分歧性具有較強的負向關聯性，而資訊品質則否。前述研究結果顯示，公司增加年報揭露項目，有助於提升各分析師對未來盈餘預測的共識，然經考量揭露內容的品質之後，其對預測分歧性的影響則較不明顯。推論原因，可能係年報揭露內容不足，使得分析師進行預測時尚須蒐集額外資訊以為彌補，以致降低年報揭露對預測分歧性的影響。

The asymptotic expression for the mean-squared prediction error is discussed for the near-unit-root models. We find the mean-squared prediction error based on the ordinary least square estimator is smaller than the one using pretest estimating under some certain conditions.

本研究從損益表角度切入，驗證分析師盈餘預測之修正與未預期盈餘組成項目變動之關係，是否有助於分析師預測公司未來盈餘的波動。實證結果顯示，分析師在不同時間點所做的預測修正與未預期盈餘組成項目變動顯著相關。分析師預測公司當期及次期盈餘時，會考量其未預期盈餘組成項目。此外，分析師預測修正與未預期盈餘組成項目之關連性與兩者之時距呈反向關係，亦即次期盈餘預測之修正與當期未預期盈餘組成項目之關係顯著較低。再者，分析師對當期（以月份為基礎）盈餘的累積預測修正與上一期的未預期盈餘組成項目息息相關，且隨著時間的推移，二者之關連程度愈趨明顯。整體而言，損益表盈餘組成項目之變動對分析師在不同時間點所做之盈餘預測，具有價值攸關性。 / This study examines whether earnings components can help financial analysts predict firms’ earnings by investigating the association between analysts’ forecast revisions and firms’ unexpected changes in earnings components. Our results show that analysts’ forecast revisions made in different time horizons are consistently associated with unexpected changes in earnings components. Financial analysts are able to incorporate current-year unexpected earnings components into their current and future earnings forecasts even before firms officially release this information. Current-year’s unexpected earnings components are, however, not fully incorporated into analysts’ forecasts of future earnings. Analysts appear to wait for more information releases regarding firms’ future earnings and delay their revisions of future earnings forecasts. This is consistent with the evidence that the cumulative revisions of current earnings forecasts are generally associated with its prior-year’s unexpected earnings components, and the association appears to be stronger as time progresses. Overall, this study provides evidence suggesting that earnings components do have value relevance and can help financial analysts identify firms’ earnings changes over time.

本研究主要探討公司設置獨立董監事及其專業性，對於分析師進行公司盈餘預測時是否會產生影響。由於上市櫃審查準則的規範，本研究將樣本分為兩群，第一群樣本為受此準則規範，須強制設置獨立董監事之IPO公司，第二群樣本為不受此準則規範之上市櫃公司，以研究透過獨立董監的設置，是否會對分析師行為產生影響。 研究結果發現，獨立董事的設置有助於降低分析師預測離散度，尤其是具有專業背景之獨立董事，對於降低分析師的預測誤差及預測離散度有顯著影響；在獨立監察人方面，僅具專業背景之獨立監察人對於提升分析師跟隨人數有顯著影響。另外，亦發現受規範公司樣本對於分析師預測行為之影響力明顯大於不受規範公司樣本，本研究推論其原因為國內除了新上市櫃有因應法規之需求而設置獨立董監事外，一般上市櫃公司並無強大誘因促使其設立獨立董監事，造成自願設置之樣本數量過少，而導致其實證結果不顯著。 / This study investigates the effect on the forecasting behavior of analysts through employing independent directors or independent supervisors and their professional background. According to the listed examination criterion of TSEC and OTC, the samples are classified into two groups: companies regulated by the law and non-regulated companies. The empirical results suggest that independent directors contribute to reducing forecasting dispersion of analysts. Furthermore, independent directors who have professional background contribute to reducing forecasting dispersion and forecasting error of analysts. In terms of independent supervisors, only people who have professional background are positively related with analyst following. The results also show that regulated companies have more significant influence on analysts than non-regulated companies do, indicating that in response to the listed examination criterion of TSEC and OTC, regulated companies have to employ independent directors and independent supervisors. On the other hand, there is no motive for non-regulated companies to employ independent directors and independent supervisors, resulting in no significant impact on forecasting behavior of analysts.

本論文分為兩部分，第一部份探討日經225和摩根台指成分股調整的價格變動效果。第二部份則是探討分析師對於股票被納入日經225和摩根台指的盈餘預測反應和絕對預測誤差。 / Two essays are comprised in this dissertation to examine the effects of changes in price and the analyst responses of earnings forecasts to stocks Indices adjustments. Stock markets vary in nature from one country to another and the characteristic of stock index adjustments also alter significantly. The analytical results can provide better information for investors and management to make better decisions. In the first essay, we examine price effects associated with changes in the composition of the Nikkei 225 Index and MSCI Taiwan Index. The analytical results show the price effects on stocks experiencing adjustments in the Nikkei 225 Index are consistent with the price pressure hypothesis. The price effects of composite stocks changed for the MSCI Taiwan Index are consistent with the downward sloping demand curve hypothesis. Based on classifying the characteristics of composite stocks into three categories, we find that large-scale added stocks dominate the price trend of the whole added sample in the Nikkei 225 Index. Also, added stocks with upwards revision earnings forecasts make more abnormal returns than the added stocks with downwards revision earnings forecasts in the Nikkei 225 Index during the post-announcement period. The electronic stocks earn larger abnormal returns than non-electronic stocks in the MSCI Taiwan Index. That can enable investors to profit by buying electronic stocks and added stocks with upwards revision earnings forecasts. The price reactions for the composite stocks in the Nikkei 225 Index and MSCI Taiwan Index around the Internet bubble burst have significantly difference. In the second essay, we study the earnings forecast changes and absolute forecast errors made by analysts of the Nikkei 225 Index and MSCI Taiwan Index. Depending on the properties of brokerage firms that analysts work for, we divide them into local analysts and foreign analysts to separate who are more accurate than one the other. The results show that in comparison with the matching firms in Japan, the magnitudes of mean forecast revisions and absolute forecast errors are smaller made by analysts focusing on firms newly added to the Nikkei 225 Index. For firms newly added to the MSCI Taiwan Index, the magnitude of changes in analysts EPS forecasts do not differ clearly from those of their peer groups. Absolute forecast errors made by analysts focusing on firms newly added to the MSCI Taiwan Index are smaller than those made by analysts focusing on the matching firms. This phenomenon demonstrates firms that are newly added to the Nikkei 225 Index and MSCI Taiwan index exhibit significantly improved performance. In terms of the relative accuracy of local and foreign analysts, the results display that the forecasts of foreign analysts are less accurate than those of local analysts in Japan and the forecasts of foreign analysts are more accurate than those of local analysts in Taiwan.

明天股票的價格是會漲還是會跌呢? 明天到底會不會下雨? 下期樂透開獎會是哪些號碼呢? 未來不知道會發生哪些事情? 大家總是希望能夠未卜先知、洞悉未來! 可是我們要如何進行預測呢? 本文比較了不同時間序列模型的預測績效, 而且測試預測的結合是否能夠改進預測的準確度? 時間序列模型的研究在近年來非常蓬勃地發展, 所以本文簡單介紹了時間序列模型(Time series models)當中的線性AR模型、非線性TAR模型、非線性STAR模型, 以及這些模型該如何來進行在樣本外的預測。 同時本文說明了預測的結合(Combined forecast)該如何進行? 預測結合的目的是希望能夠達到截長補短的效果! 除了傳統迴歸(Regression-based)方法和變動係數(Time-varying coefficients)方法外, 本文提出了兩種非迴歸類型的預測結合方法, 績效權數(Fitness weight)和支向機(Support Vector Machine)。 其中主要的焦點放在支向機, 因為迴歸方法可能會有共線性的問題, 支向機則是沒有這個問題。 本文實證的結果顯示, 在時間序列模型方面, 非線性模型的預測能力, 在大多數的情形底下, 都不如簡單的線性AR模型; 在預測結合的方面, 支向機的績效是和迴歸方法的績效是差不多的, 這兩者都比變動係數方法的績效來得穩固, 可是如果基底模型的預測值存在共線性的問題或樣本數目過少的問題, 那麼支向機的績效是優於迴歸方法的績效。 最後, 時間序列模型的預測績效會受到資料性質的影響, 而有極大的改變, 或許我們可以考慮使用比較保險的預測策略-預測結合, 因為預測結合的預測誤差範圍是小於時間序列模型的預測誤差範圍!

當企業的經營面臨不確定的情況時，使用穩健原則固然是可靠的，但是公司如果過度的使用穩健原則來操縱財務報表，將使資產和盈餘嚴重低估和扭曲，因此反而會降低財務報表的可靠性以及攸關性。公司的財務報表是財務分析師預測的來源之一，故當公司的盈餘由於受到管理當局對會計保守程度之操縱而有較大波動幅度時，若分析師相信公司當期盈餘是對未來盈餘的無偏誤預測指標，則財務分析師將會被誤導。因此，公司的會計保守程度對分析師盈餘預測的誤差和不同分析師間對盈餘預測意見不一致之程度應該有重大的影響。 　　本文以民國90年至94年之上市公司為研究對象，經由迴歸模型來分析公司會計保守性與分析師盈餘預測誤差與盈餘預測分歧程度間之關係，以檢視財務分析師是否能察覺保守性會計對公司盈餘的影響而反映於其盈餘預測中。結果發現會計保守性對分析師盈餘預測屬性均有正向影響，表示財務分析師在預測公司未來盈餘時會對管理當局所選擇的會計保守程度加以評估，並考量管理當局利用會計保守性進行盈餘管理的情形，進而影響其對公司未來盈餘的預測。 / Management may overuse accounting conservatism to manage the financial statements and undervalue assets and earnings and reduce the reliability and relevance of financial statements though conservatism is an increasing trend in accounting practice. The conservative information may lead analysts to biased forecast when a company’s earning has high volatility. Consequently, the extent of accounting conservatism should have significant effect on the analysts’ earnings forecast errors and forecast dispersion. This study examines the relationship of accounting conservatism and analysts’ annual earnings forecast errors and forecast dispersion by using a sample of listed firms in Taiwan. The results show that accounting conservatism has a positive relationship with the analyst earnings forecast errors and forecast dispersion. It implies that financial analysts may evaluate the extent of accounting conservatism and make adjustment in earnings forecast.