The contrarian model assumes that inferior (superior) past performance can be used as a good indicator of future superior (inferior) performance. In this regard, recent research has integrated the relevance of business magazine cover stories as a possible indicator of this performance, serving as a signal to investors to adopt a particular contrarian investment strategy. This research study replicates with extension a United States-based study that examined whether cover stories acted as effective contrarian indicators. Cover stories from the Financial Mail were collected for a ten-year period to determine whether the nature of the content (classified as either negative, positive or neutral) can act as a useful predictor of future investment performance. The event study method was used to establish whether this future performance was contrarian or momentum in nature, by adjusting the featured company holding-period returns with three benchmark measures: the FTSE-JSE All Share index; a sector-specific index; and an industry-size-matched (ISM) peer company. Statistical tests suggested that while positive stories provided evidence of momentum holding-period return (HPR) performance, negative stories showed weak evidence of contrarian performance for a two-year period. However, when HPR was adjusted for sector or ISM index, most of the abnormal returns dissipated, with only weak evidence of contrarian performance for positive stories and momentum performance for negative stories. The results validated those of the United States-based study, that suggested that magazine cover stories do not function as suitable indicators of either momentum or contrarian performance. Copyright / Dissertation (MBA)--University of Pretoria, 2010. / Gordon Institute of Business Science (GIBS) / unrestricted

Background: In financial markets, decisions to buy or sell securities are highly influenced by the aim of making a profit and avoiding losses. The signals that insider transactions send to external investors can significantly impact those decisions. The signals can differ depending on the type of transaction, within which sector, and the company's size. Purpose: The purpose of this thesis is to investigate whether insider transactions employ a more potent influence when buying or selling stocks. A partial purpose is distinguishing between small- and mid-cap stocks and between the technology and industrial sectors on the Nasdaq Stockholm Stock Exchange. Methodology: A quantitative approach was utilised with the event Study model. Hypotheses were constructed, and statistical tests in STATA were conducted to determine if the results were significant. The insider trading that was analysed took place between 2018-2023. Thirty-one companies are in the industrial sector, and twenty-eight are in the technology sector, with 3601 insider transactions employed. Conclusion: The results showed the existence of signalling effects and the possibility of achieving abnormal returns, especially if shorting when insiders are selling, particularly technology stocks, with the most prominent returns from mid-cap firms. However, the results contradict most previous research proposing that purchase transactions yield higher abnormal returns and have a more substantial signalling effect.

The study aims to detect the influence of the initial cross-listing of Taiwanese enterprises on the variety of the stock price of the listing company and its rival firms. However, the limitations from the Taiwanese authorities on the local company¡¦s direct listing in the oversea market are not a few. Accordingly, I employ GDR instead of direct international listing to delve the phenomenon of information content and intra-industry transfer derived from a company¡¦s initial GDR offering. Recent studies focusing on the same issue rarely inspect the situation of Taiwanese industries. Thus, the research intends to excavate the effect and the aftermath of a Taiwanese firm¡¦s initial GDR offering on its local market price as well as on the one of its rival company that concurrently does not have GDR offering. To delineate the complication of the issue, the study develop three trajectories mainly based on various approaches, including reference review, event study method, and multi-regression analysis. The first aspect attends to the research result of event study method and multi-regression analysis that exposes the stock price of the GDR offering company has abnormally positive rise accompanying with the announcement of its GDR offerings, particularly in the period before the announcement. That reflects the investors regard the GDR offering as a positive news for a company while the situation turns out to be the opposite for the rival firms. The research also finds that industry differences might dominate the consequence of the GDR offering. Hence, the exemplary simples are divided into the ¡§hi-tech¡¨ industry group and the ¡§non hi-tech¡¨ industry group. Based on the reference review of Melvin and Valero-Tonone¡]2005¡^ and the outcome of the multi-regression analysis, the influence of GDR offering on both industry group will be carefully scrutinized. In addition, the study places another attention on the discussion of intra-industry transferring and the contagion effect of the GDR offering on the offering company and its rival firm. Although Taiwanese enterprises offer GDR mainly in four main trade locations from London, Luxembourg, New York, and NASDAQ, the study exposes that the trade location has less influence on a company¡¦s and its rival firm¡¦s SCAR variation. That implies that Taiwanese investors might recognize the fact of a company¡¦s GDR offering in the oversea market, whereas, they seldom be aware of the trivial differentiation of the disparate trade location. In conclusion, the GDR offering of Taiwanese enterprises indeed encompasses information content that might motivate the alteration of the stock price in Taiwan stock market. Besides, the action of GDR offering supplies intra-industry information transferring effect. Even though the strategy of offering GDR of a Taiwanese company does not rely on consulting the action of its rival firms, in reality and according to the application of game theory, the implementing efficiency of a company¡¦s strategies might probably be impinged by its opponents¡¦ behavior. In other words, while a company offers GDR, its rival firms should propose expedients to reduce the damage that might be caused by the issue information.

根據效率市場假說（Efficient-market hypothesis，EMH），倘若市場是具有效率性的，投資者無法預測股票未來的走勢，包括專業的基金經理人員。但是，在許多財經新聞媒體、商業報紙與商業週刊中，發現證劵經理人或分析師在金融市場中大膽的預測股票未來的走向。這些資訊吸引許多投資者紛紛進場投資，期許能獲得更多利潤。然而，投資者卻忽視發佈的資訊時間點的重要性，幾乎很難求證此消息是否真實。本研究希望探討投資機構之研究彙報能否為投資者帶來異常報酬，並印證市場效率性是否存在。本研究資料透過公開的資訊網站Yahoo Finance收集美國道瓊工業30成份股的資料之金融研究機構建議操作方向，利用事件研究法(Event Study Method)來進行分析。實證結果發現事件發生時，不論是推薦買進或賣出，平均異常報酬率（AAR）有顯著的異於零的報酬率，證實金融研究機構所建議的操作方向的確吸引到市場的注意，造成股價異常波動。而累計平均異常報酬率（CAAR）則是顯示事件發生後約4週，建議買進的事件會出現相當利潤。除此之外，本研究亦針對不同金融研究機構的績效分別進行討論，然而並無發現各金融研究機構有顯著的差異。 / According to the Efficient-Market hypothesis (EMH), if the market is to have efficiency, the investor or professional fund managers cannot predict the future trends of a stock. However, in many financial news media, business newspapers and Business Week, we can find securities managers or analysts in the financial markets boldly predicting the future direction of a stock. This information attracts many investors who enter into investments, hoping to gain more profit. However, investors have neglected the importance of published information at a point in time, and in hindsight, it was hard to verify whether or not this news is true. The present study is to investigate that the mechanism of investment research reports can bring abnormal returns for investors, and confirm the existence of market efficiency. The studies suggested actions of directing public information through research institutions news site Yahoo Finance and collected 30 constituent stocks of the Dow Jones Industrial, to analyze the use of the event study method. The empirical results show when the event occurred, whether it was a buy or sell recommendation, the average abnormal return rate（AAR）has a phenomenal rate of return difference from zero, confirming that the proposed research institutions operating direction did attract the market's attention, resulting in abnormal fluctuations of the stock price. The cumulative average abnormal return rate（CAAR） is a show about four weeks after the incident that recommends buying the event will be quite profitable. In addition, this study discussed separately the performance of different research institutions, however, it found no significant differences between various research institutions. / 目錄 摘要.............................................................................................................Ⅰ Abstract........................................................................................................Ⅱ 目錄............................................................................................................Ⅲ 圖目錄..........................................................................................................Ⅴ 表目錄..........................................................................................................Ⅵ 第壹章 緒論....................................................................................................1 第一節 研究動機.................................................................................................1 第二節 研究目的................................................................................................2 第三節 研究架構.................................................................................................3 第四節 研究貢獻.................................................................................................3 第貳章 文獻回顧.................................................................................................3 第一節 效率市場理論..............................................................................................3 第二節 效率市場層面..............................................................................................5 第三節 專家推薦層面..............................................................................................7 第四節 綜合評析..................................................................................................8 第參章 資料來源與研究方法.........................................................................................8 第一節 資料來源..................................................................................................8 第二節 研究方法.................................................................................................10 第肆章 實證分析.................................................................................................11 第一節 資料敘述.................................................................................................11 第二節 模型設計.................................................................................................13 第三節 結果分析.................................................................................................20 第伍章 結論與建議...............................................................................................33 第一節 結論....................................................................................................33 第二節 後續研究建議.............................................................................................35 參考文獻.........................................................................................................36 中文部分.........................................................................................................36 英文部分.........................................................................................................37 附錄.............................................................................................................38 附錄一 道瓊30成分股中之各證劵彙報建議買進(Upgrade)之個股平均異常報酬（AAR）與累計平均異常報酬（CAAR）圖..................38 附錄二 道瓊30成分股中之各證劵彙報建議賣出(Downgrade)之個股平均異常報酬（AAR）與累計平均異常報酬（CAAR）圖................45 附錄三 篩選後，各家金融研究機構發佈彙報之建議買進(Upgrade)之個股平均異常報酬（AAR）與累計平均個股異常報酬（CAAR）圖........52 附錄四 篩選後，各家金融研究機構發佈彙報之建議賣出(Downgrade)之個股平均異常報酬（AAR）與累計平均個股異常報酬（CAAR）圖......57 圖目錄 圖1. Fama et.al.之資本市場效率分成三種假說特性.......................................................................5 圖2. 事件研究法模型的時間線圖.......................................................................................15 圖3. 道瓊30成分股之全部研究彙報建議買進(Upgrade)的平均個股異常報酬（AAR）圖............................................28 圖4. 道瓊30成分股之全部研究彙報建議買進(Upgrade)累計平均個股異常報酬（CAAR）圖..........................................28 圖5. 道瓊30成分股之全部研究彙報建議賣出(Downgrade)的平均個股異常報酬（AAR）圖...........................................29 圖6. 道瓊30成分股之全部研究彙報建議賣出(Downgrade)累計平均個股異常報酬（CAAR）圖........................................29 表目錄 表1. 道瓊30工業指數之成分股（Dow Jones Industrial Index of 30 stocks, ^DJI）.........................................9 表2. 所有金融研究機構有給予道瓊30成分股的總發佈彙報次數................................................................12 表3. 道瓊30篩選後之金融研究機構與彙報發佈次數.........................................................................13 表4. 道瓊30成分股中個別證劵建議買進(Upgrade)的平均個股異常報酬（AAR）...................................................24 表5. 道瓊30成分股中個別證劵建議賣出(Downgrade)的平均個股異常報酬（AAR）.................................................25 表6. 道瓊30成分股中個別證劵建議買進(Upgrade)的累計平均個股異常報酬（CAAR）...............................................26 表7. 道瓊30成分股中個別證劵建議賣出(Downgrade)的累計平均個股異常報酬（CAAR）.............................................27 表8. 篩選後，各家金融研究機構發佈彙報之建議買進(Upgrade)的平均個股異常報酬（AAR）.........................................30 表9. 篩選後，各家金融研究機構發佈彙報之建議賣出(Downgrade)的平均個股異常報酬（AAR）.......................................31 表10. 篩選後，各家金融研究機構發佈彙報之建議買進(Upgrade)的累計平均個股異常報酬（CAAR）...................................32 表11. 篩選後，各家金融研究機構發佈彙報之建議賣出(Downgrade)的累計平均個股異常報酬（CAAR）.................................33

Les carteres d'aliances importen? Com afecten els recursos als quals les empreses accedeixen per diverses aliances estratègiques simultànies amb socis diferents a la creació de valor i a l'apropiació de valor? Les carteres d'aliances expliquen l'heterogeneïtat entre empreses respecte del valor que capten quan entren en noves aliances estratègiques? Aquesta tesi doctoral es basa en la teoria dels recursos i en la bibliografia sobre el comportament estratègic i les dinàmiques competitives, i presenta un model teòric que es refereix a la creació de valor i l'apropiació en empreses que accedeixen a recursos a través de diverses aliances simultànies amb socis diferents. El model mostra que la creació de valor en les carteres d'aliances és una funció del valor creat per combinacions sinergètiques de recursos que impliquen recursos als quals tenen accés diferents socis, com també del valor destruït a causa de la incompatibilitat entre la combinació de recursos d'una empresa focal i els recursos dels seus socis. Sobre la base d'aquest model teòric, s'han desenvolupat diverses hipòtesis en un ambient marginal en què una empresa connectada multilateralment afegeix una nova aliança estratègica a la seva cartera d'aliances. Per comprovar aquestes hipòtesis, s'ha emprat la metodologia de l'event study i s'han utilitzat dades de la indústria de els línies aèries globals sobre acords de code share subscrits entre 1994 i 1998. Els resultats mostren que el mercat recompensa les empreses que formen aliances amb socis que tenen recursos complementaris i poden aportar recursos que no només es poden combinar amb els recursos propis de l'empresa sinó també amb els relacionals i que també són compatibles amb els dels socis que formen l'aliança. D'altra banda, els resultats també mostren que el mercat penalitza les empreses que formen aliances que aporten recursos incompatibles amb les carteres d'aliances, atès que creen un conflicte competitiu amb alguns dels socis existents. Els resultats de la part empírica d'aquesta anàlisi abonen la tesis que les carteres d'aliances afecten els resultats de les empreses que entren en aliances estratègiques. Aquest estudi conclou que els recursos als quals es té accés per mitjà d'aliances entre empreses s'han d'avaluar no tan sols per les seves característiques pròpies y diàdiques sinó també en el context de les carteres d'aliances. / ¿Importan los portafolios de alianzas? ¿Cómo afectan los recursos a los que acceden las empresas por varias alianzas estratégicas simultáneas con socios diferentes a la creación de valor y a la apropiación de valor? Los portafolios de alianzas ¿explican la heterogeneidad entre empresas con respecto al valor que captan cuando entran en nuevas alianzas estratégicas? Esta tesis doctoral se basa en la teoría de los recursos y en la bibliografía sobre el comportamiento estratégico y las dinámicas competitivas, y presenta un modelo teórico que se refiere a la creación de valor y apropiación en empresas que acceden a recursos a través de varias alianzas simultáneas con socios diferentes. El modelo muestra que la creación de valor mediante un portafolio de alianzas es una función del valor creado por combinaciones sinergéticas de recursos que implican recursos a los cuales acceden diferentes socios, así como del valor destruido a causa de la incompatibilidad entre la combinación de recursos de una impresa focal y los recursos de sus socios. Sobre la base de este modelo teórico, se han desarrollado varias hipótesis en un ambiente marginal en el que una empresa conectada multilateralmente añade una nueva alianza estratégica a su cartera de alianzas. Para comprobar estas hipótesis se ha empleado la metodología del event study, y se han utilizado datos de la industria global de las aerolíneas sobre acuerdos de code share suscritos entre 1994 y 1998. Los resultados muestran que el mercado recompensa a las empresas que forman alianzas con socios que tienen recursos complementarios y pueden aportar recursos que no sólo pueden combinarse con los recursos propios de la empresa sino también con los relacionales y que también son compatibles con los de los socios que forman la alianza. Por otra parte, los resultados también muestran que el mercado penaliza a las empresas que forman alianzas que aportan recursos que son incompatibles con los portafolios de alianzas, en el sentido de que crean un conflicto competitivo con algunos de los socios existentes. Los resultados de la parte empírica de este análisis abonan la tesis de que los portafolios de alianzas afectan a los resultados de empresas que entran en alianzas estratégicas. Este estudio concluye que los recursos a los que se accede a través de las alianzas entre empresas han de evaluarse no sólo por sus características propias y diádicas sino también en el contexto de los portafolios de alianzas. / Do alliance portfolios matter? How do resources accessed from multiple simultaneous strategic alliances with different partners affect value creation and value appropriation? Do alliance portfolios explain heterogeneity across firms with respect to the value that they derive from entering into new strategic alliances? This dissertation builds on insights from the resource-based view of the firm and the strategic behaviour and competitive dynamics literature and advances a theoretical model that addresses value creation and appropriation in firms that access resources through multiple simultaneous inter-firm alliances with different partners. The model illustrates that value creation on the alliance portfolio level is a function of the value created from synergistic resource combinations involving resources accessed from different partners as well the value destroyed by incompatibilities between a focal firm's resource combinations and those deployed by its partners. Based on this theoretical model, empirically testable hypotheses are developed in a marginal setting, in which a multilaterally connected firm adds one new strategic alliance to its alliance portfolio. The hypotheses are tested using an event study method approach and data from the global airline industry on code share agreements formed between 1994 and 1998. The results show that the market on one side rewards firms entering into strategic alliances with partners that possess complementary resources and that contribute resources that cannot only be combined with firms' own but also existing relational resources and that are compatible with the firms' alliance portfolios. On the other side, results show that the market penalizes firms entering into alliances that contribute resources that are alliance portfolio incompatible in the sense that they create a competitive conflict with some of the existing alliance partners. The findings of the empirical part of this dissertation support the view that alliance portfolios affect the performance of firms entering into strategic alliances. This study concludes that resources accessed through inter-firm alliances should not only be evaluated on their standalone and dyadic attributes but also in the context of alliance portfolios.