京都大学 / 新制・課程博士 / 博士(経済学) / 甲第24374号 / 経博第661号 / 新制||経||302(附属図書館) / 京都大学大学院経済学研究科経済学専攻 / (主査)教授 西山 慶彦, 教授 江上 雅彦, 教授 秋田 祐哉 / 学位規則第4条第1項該当 / Doctor of Economics / Kyoto University / DGAM

Magister Commercii - MCom / The efficient market hypothesis (EMH) is a controversial theory in Finance. Advocates of the EMH argue that it provides a basis for understanding financial markets while critics suggest that the hypothesis is unreasonable in its assumptions of the real function of these markets. Although the EMH may not be perfect, it provides a sufficient baseline against which financial markets may be analysed. Over the past couple of years, academics have broadly examined the EMH in both developing and developed financial markets. However, limited research has been done on African markets. Therefore, this study examines the weak-form EMH of the Johannesburg Stock Exchange (JSE) after 2008 to ascertain the impact the 2008 global financial crisis had on its efficiency. This study analysed the JSE using weekly and monthly returns of the three major indices (RESI 10, FINI 15, INDI 25) as well as the individual companies under these indices from 30th January 2009 to 30th January 2019. Analysis was carried using various statistical tests i.e., runs test, variance ratio test, unit root tests, and a GARCH model which revealed mixed results. Results of the unit root tests (ADF and PP) confirm that the JSE is weak-form efficient when both the weekly and monthly data of the indices and individual companies are analysed. The results of the runs test reveal that all the weekly and monthly data apart from the weekly data of the companies under RESI 10 index exhibit weak-form efficiency. The variance ratio test confirms weak-form inefficiency when weekly data is used while the monthly data confirms weak form efficiency of the JSE and shows that the market moves from periods of efficiency to periods of relative predictability. The results of the GARCH model on the other hand confirm the weak-form efficiency of the JSE when both the weekly and monthly data of the indices are analysed.

This thesis investigates the price discovery process between the stock and the credit default swap market (CDS). We link the financial theory of efficient markets and the underlying models and conditions involved in CDSs, the stock market and financial crashes. This study uses publicly listed firms and the European market CDS series to construct a matched stock portfolio and uses financial data collected between the years 2019 to 2021. The purpose is to better understand the price discovery process during a potential new type of crisis in modern financial history. It could potentially allow portfolio managers, traders, arbitrageurs and stakeholders who monitor systematic indices to gauge the level of risk in the overall economy. It can also better inform regulators about how the CDS and the stock market reacted to each other during the COVID-19 pandemic. This deductive and quantitative research is based on secondary data gathered from the Eikon financial database. It uses a vector autoregressive model to test a hypothesis regarding the price discovery process between the stock and CDS portfolios.  Our results show that when using only the variables for the CDS and stock market, both variables cause each other, which is to say a feedback effect is present between the CDS Europe index and the matched portfolio of stocks. When adding the three control variables, the stock variable no longer causes the CDS variable, while the CDS variable still causes the stock variable. We conclude that the European credit default swap index leads the matched portfolio of stocks in the price discovery process with our chosen variables.

This study addresses the empirical question of heterogeneous market efficiency characteristics, specifically as they are attributable to divergent levels of professional securities analyst attention. As a significant group of information intermediaries, analyst institutions conceivably influence, in a profound manner, the efficiency with which security prices respond to new information. Consistent with this notion is the hypothesis that the securities of firms which are neglected in terms of analyst coverage exhibit price inefficiencies relative to their closely followed counterparts. Two market efficiency constructs with respect to annual earnings announcements are examined in this study. Preannouncement information efficiency is guaged by the degree to which security prices appear to lead or anticipate the information content of subsequent public earnings releases. Such price behavior is indicative of the market's ability to acquire and, process interim, signals that are relevant to the determination of proper and timely security valuations. Postannouncement, or semi-strong-form, efficiency is in turn referenced by the relative absence of anomalous "drifting" patterns in postdisclosure returns. The presence of significant drifts is inconsistent with a market that adjusts quickly and unbiasedly to signals that are transmitted publicly. Sample firms taken from the NYSE are ranked into three groups according to their relative following by the professional securities analyst community. Analyst attention is surrogated by the number of investment houses providing annual earnings per share forecasts for companies listed in the Institutional Brokers Estimate System (IBES) computer file. The delineation of the three attention concentration groups' relative efficiency profiles is accomplished by means of two uniquely derived metrics that restate cumulative abnormal returns (CAR's) into an ordered domain of pre- and postannouncement efficiency structures. The CAR's are derived from dailly price data immediately surrounding annual earnings announcement dates for the calendar years ended 1976 through 1982. Owing to the nonnormal distributional properties of the inefficiency metrics, two nonparametric procedures are employed to detect group mean differences. The results overwhelmingly indicate that both pre- and postannouncement efficiency are positively associated with professional analyst attention. Moreover, the detected efficiency differences cannot be attributed to firm size effects or to the extent of the market's forecast error -- two factors that have previously been established in the empirical literature to be associated with event period CAR magnitudes. / Ph. D.

Whether insiders can use informational advantage when purchasing or selling their company stocks to generate cumulative abnormal returns (CAR) has shown different results in several markets. The Swedish market is yet to be extensively examined, and this thesis aims to understand how insiders in the OMXS30 companies perform when testing CAR and if there exists an information asymmetry. A predicted return is generated through the market model to calculate CAR, and the same index OMXS30 is combined with stock return data. We conducted an event study through Stata to match the transactions with a particular trading day to see how the insiders' transaction yielded CAR. We find that significant CAR exists for all insider groups for various event windows and find a difference in significant CAR for both genders and insider positions. The results were robust when we changed to a new market index as the independent variable in our regression analysis. The results align with previous literature, stating that insiders generated significant CAR from insider trading and differences between insider position and gender (Jeng et al. 2003; Jiang & Zaman, 2010; Lasfer & Ye, 2023). The findings can be used for regulatory purposes when investigating information asymmetry.

Purpose: The purpose of this paper is to examine if underlying psychological factors have an impact on shareholders' investment decisions and if forecasting quarterly reports have an impact on shareholders' investment decisions. Methods: The study combines an application of two different methods, survey and an event study. The purpose of the survey was to investigate if psychological factors interfere with shareholders' investment decisions. The Event study is designed to measure equity market reaction to the forecasts and if any changes occurred in the companies' share price. Theoretical: This study is based on established theories in the fields of behavioral finance, the efficient market hypothesis and the economic man. Conlusion: Underlying psychological factors have a certain impact on the shareholders' investment decisions. Both events study and survey, in particularly the part of the survey, which includes forecasts, showed that the shareholders are not affected by the forecasts published by market analysts.

published_or_final_version / Architecture / Master / Master of Philosophy

Syfte: Studiens syfte var att undersöka om det uppstår onormal avkastning för målföretagets aktieägare vid offentliggörandet av företagsförvärv på den svenska aktiemarknaden, samt att undersöka om den svenska aktiemarknaden är effektiv enligt den effektiva marknadshypotesen. Metod: I uppsatsen tillämpades en eventstudie för att studera den onormala avkastningen. Datainsamlingen har skett från Thomson Reuters Eikon, Orbis, Zephyr och Retriver. Studiens dataunderlag har analyserats och presenterats i figurer och tabeller. Resultatet bygger på hypotesprövning och signifikanstest av framräknade onormala avkastningar.  Resultat & slutsats: Resultatet visade att målföretagens aktieägare vid offentliggörandet av företagsförvärv i genomsnitt erhöll en hög positiv onormal avkastning under perioden 2011 till 2016, samt att den svenska aktiemarknaden var effektiv. Detta genomsnittliga värde var statistiskt signifikant på signifikansnivån 0,01 procent. Förslag till fortsatt forskning: Ett förslag till vidare forskning är att undersöka ett längre tidsspann, vilket kan öka populationens storlek. Vidare forskning kan även undersöka om olika faktorer i företagsförvärvet kan förklara de erhållna onormala avkastningarna.  Uppsatsens bidrag: Studien bidrar med relevant information till företagsledningar, finansanalytiker och företagsintressenter. Detta eftersom studiens resultat skapar förståelse för företagsförvärv i en svensk kontext och kan därför ligga till grund för beslutsfattande, värderingar och beräkningar av framtida företagsförvärv. / Aim: The aim of the study is to examine if the target company shareholders receive an abnormal return on the day of the announcement, on the Swedish stock market. The study also examines if the Swedish stock market is efficient according to the efficient market hypothesis. Method: The study was conducted according to the event study methodology. The data was collected from Thomson Reuters Eikon, Orbis, Zephyr and Retriever. The findings in the study was displayed and analysed in figures and tables. Hypothesis test and test of significance were used to investigate the aim of the study. Findings and conclusions: For the time period studied, 2011 to 2016, the target company shareholders on average received a high positive abnormal return on the day of the announcement, which was significant on the one percent level. The findings also indicates that the Swedish stock market is efficient according to the efficient market hypothesis. Suggestions for future research: One suggestion for future research could be to expand the time interval, which could increase the size of the population. Future research could also take the characteristics of the acquisition in consideration in an attempt to explain the abnormal returns found in this study.  Contribution of the thesis: This study’s findings are relevant for the chairmen of the board, finance analysts and corporate stakeholders. The findings in this study provides an understanding of the nature of acquisitions on the Swedish stock market, which can be used for decision making, evaluations and calculations of future acquisitions.

Efficient Market Hypothesis (EMH) has been the central assumption of financial modelling in the previous decades. At its core, it is a statement about the efficient incorporation of available information in the prices of assets, rendering each price a 'true' representation of the asset's intrinsic value. The notion of informationally efficient financial markets has been, since its formulation, entrenched in the very core of our understanding of how asset pricing works, yet, with ever so increasing frequency, when subjected to empirical scrutiny, it fails to prove its explanatory and predictive prowess. New academic strands emerged have emerged as a result, attempting to explain those empirical short-comings, with rather mixed results. The new models and theories often either explain a singular anomaly, rather than pro- viding a generalized and consistent theoretical framework, or are exclusive with the general state of financial markets, which tends to be efficient and rational. This thesis shall explore the relationship of information and financial mar- kets, taking into account developments that have occurred since the inception of the EMH. Subsequently it will present a new theoretical model for asset pric- ing and ipso facto the efficiency of financial markets, based on meta-analysis of information, along...

Bakgrund: Det finns olika investeringsstrategier som investerare kan använda sig av, att investera i låga multiplar är en strategi som har studerats väl. Genom att använda sig av låga multiplar kan investerare finna undervärderade bolag som på sikt genererar en överavkastning gentemot marknaden.  Syfte: Studiens syfte är att analysera hur väl P/E, P/B, P/S, EV/EBIT, EV/EBITDA och EV/S multiplarna skulle kunna appliceras som investeringsstrategi på Stockholmsbörsen. Vidare ämnar studien åt att analysera om det är möjligt att generera en högre avkastning än vad indexet OMXSPI har avkastat under tidsperioden 2008-2018. Metod: Studien använder sig av en kvantitativ forskningsstrategi där två portföljer för respektive multipel har sammanställts. Portföljerna viktas om årligen och både den verkliga och den ackumulerade avkastningen beräknas fram. Vidare utvärderas portföljerna enligt utvärderingsmåtten Sharpekvot, M^2, Treynorkvot och Jensens Alpha. Resultat: Investeringsstrategin är implementerbar för tre av sex multiplar. Låga P/B, EV/EBIT och EV/EBITDA genererade en överavkastning och slog både index samt respektive hög portfölj. Medan för de resterande multiplarna P/E, P/S och EV/S resulterade det i att investeringsstrategin inte är implementerbar. EV/S hade den högsta riskjusterade överavkastning och presterade bäst av samtliga sex multiplar. Studieresultatet för samtliga multiplar kan statistiskt säkerställas med en signifikansnivå på 5%. Den månatliga portföljavkastningen är inte slumpmässig, utan marknadsavkastningen har en viss påverkan. / Background: There are several investment strategies investors can use, where the strategy to invest in low multiples is well studied. By using low multiples investors can find undervalued companies to generate an excess return. Previous studies have been focusing on the P/E and EV/EBITDA- multiples, and not as much on other used multiples in relative valuation. Therefore an interest exists to also analyze multiples such as P/B, P/S, EV/EBIT and EV/S. Purpose: The study’s purpose is to analyze how well the multiples P/E, P/B, P/S, EV/EBIT, EV/EBITDA and EV/S can be applied as an investment strategy in the Stockholm Stock Exchange. Furthermore the study aim to analyze the possibility to generate a higher return than the index OMXSPI during the time period 2008-2018. Method: The study uses a quantitative research strategy, where two portfolios for each multiple has been created. The portfolio has been reinvested once a year, both the real and accumulated return was calculated. Also, the portfolios’ performance has been evaluated by adjusting it to risk by using the Sharpe ratio, M^2 , Treynor ratio and Jensen’s Alpha. Result: The investment strategy can be implemented for three of six multiples. The low P/B, EV/EBIT and EV/EBITDA generated a higher return than both index and their respective high portfolio. The other multiples P/E, P/S and EV/S cannot be used as an investment strategy. The high EV/S portfolio had the highest risk adjusted excess return meanwhile P/S had the highest accumulated return. The result of all multiples has been found to be statistically significant, therefore the market return has an effect on the portfolios’ monthly return.