我們把經濟體視為一個複雜適應系統(complex adaptive system), 強調系統中異質性(heterogeneous)agent的學習適應行為與agent之間的互動性交互作用, 此時主流經濟學裡的分析架構, 如:代表性個人模型(represesentive agent model)、理性預期(rational expectation)、固定點均衡分析(fixed-point equilibrium analysis)等將不再適用, 取而代之的是演化經濟學(evolutionary economics)的研究典範, 這樣的研究架構下, 並沒有適當的數學分析工具可資運用, 因此我們改以agent-based建模(agent-based modelng)的社會模擬(social simulation)來建構一個人工的經濟體(artificial economy), 以此為主要研究方法, 這就是agent-based計算經濟學(agent-based computational economics)或稱人工經濟生命(artificial economic life)。 本文中以股票市場為主要的研究課題, 我們以遺傳規劃(genetic programming)的人工智慧(artificial intelligence)方法來模擬股市中有限理性(bounded rational)異質交易者的交易策略學習行為, 建構出一個人工股票市場(artificial stock market), 在這樣的架構下, 我們成功地產生出類似真實股票市場的股價時間序列特性, 我們同時也檢定了人工股票市場中價量的因果關係, 說明了在沒有外生因素之下, 人工股票市場的複雜系統可自發地產生出雙向的價量因果關係, 進一步地, 我們研究下層agent(交易者)行為與上層股價時間序列行為的關聯性, 我們也發現個體的行為並不能直接加總或推論出複雜適應系統的總體行為, 這就是突現性質(emergent property)的發生, 最後, 本文描述了agent-based計算經濟學研究架構的優勢與缺點, 再附帶介紹一個用以進行agent-based建模相關研究的軟體程式庫-SWARM。

本文主要在探討影響台灣股票市場波動的因素，除了考慮以之前學者設定的 VAR(12)模型研究，另外以 SUR(5)模型來討論股市波動與基本面、交易面間的關係；最後，再以自我迴歸異質條件變異數模型來分析股市波動的特性。最重要的是，我們會根據誤差項的各類檢定結果來判定研究股市波動性質的最佳模型。 在聯立方程式的估計中，我們發現代表資訊到達指標的兩變數--週轉率與成交量成長率--會影響股票市場的波動。另外，我們找出交易面（成交量成長率）可能會影響基本面（匯率），這也就是說，在研究股市波動時，我們不需要特別區分變數的屬性。 在 GARCH 模型及 TGARCH 模型中，我們仍然可發現週轉率與成交量成長率會影響股市條件平均數或條件變異數；除此之外，好壞消息對股市日報酬率條件變異數（條件波動）應有不同的影響效果（壞消息的影響力較快反應）。而股市自身風險係數雖然統計檢定上不顯著異於零，但若未加入條件平均數的估計式，則可能會使模型得到較差的誤差項檢定結果，顯見股市自身風險應為影響投資人設定期望報酬率水準的重要因素之一。 從上述估計結果，我們可以知道，若散戶投資人能正確解讀市場上出現的各種新資訊之背後意義，將可使成交量成長率或週轉率（大部份可能代表無意義或不正確的交易行為）的變動幅度降低，進而有效地減少股票市場中股價異常波動的現象。 / My essay's topic focuses on discussing the factors that influence stock market volatility in Taiwan's stock market. Besides VAR(12) model as previous researchers have studied, I tries to set up SUR(5) models analyzing the relationship among the stock market volatility、the foundamental variables'volatilities and trading activities; Then I cited ARCH models ( autoregressive conditional heteroskedisticity models ) to find out the characteristics of stock market volatility. Most important of all, according to each misspecification test ( residual test ), I would specify the better models to describe the stock market volatility. In the estimations of system equations ( VAR(12)and SUR(5)models ), first I found that turnover rate and the growth rate of trading volume, which represent the information arrival indexes, could effect stock return's monthly conditional variance. Second, I especially found out the evidence that trading activities (trading volume growth) would probably have an impact on the macroeconomic variable ( exchange rate volatility ). It shows that we don't need to distinguish the attributes of those factors which could influence stock market volatility. In GARCH and TGARCH model, the positive influences of turnover and trading volume growth on daily stock return's conditional mean and conditional variance ( conditional volatility ) are still obvious, Within these TGARCH model, I discovered that bad news and good news could have different influences on stock market volatility ( the impact of bad news which resulted in downward movements of stock market volatility appeared faster that the good news'which caused upward movements). Stock market's self-risk(σ_t-1^{^2}) is statistically insignificant different from zero in GARCH models, but when I omitted this variable in daily stock return's conditional mean estimation equation, standardized residual might not obey the assumption of normal distribution. It apparently told us that the stock market's self-risk term ( σ_t-1^{^2} ) is one of the critical factors which influences investors to estimate expected return level. From those results above, we realized that if investors could precisely understand the real meanings of new information conveying in the stock market, it might decrease the levels of turnover and trading volume growth ( which could sometimes represent meaningless or inexact trading activities ), then effectively reduce the abnormal volatility phenomenon in stock market.

本文主要探討新股初次上市(櫃)前後期間的股價反應，並藉由觀察準上市(櫃)公司正式上市(櫃)前於興櫃市場交易的股價反應，來驗證興櫃市場的價發現機能。實證結果顯示，上市(櫃)申請日起至興櫃市場最後交易日止期間平均持有報酬47.01%、上市(櫃)首日異常報酬為58.37%、正式掛牌上市(櫃)第二交易日起至一年後的報酬表現，新上櫃股票報酬為14.01%普遍優於新上市的-1.23%。 興櫃市場的價格發現機能相關研究方面，興櫃市場的價格發現機能相關研究的結論為:IPO首日超額報酬在興櫃市場就已經能率先適當反應，興櫃市場是有價格發現機能的，IPO首日超額報酬存在，很有可能是因為承銷價低估。 / This research aims to investigate the performance of IPO stocks during their offering. Our sample consists of IPO announced from March 1, 2005 to February 28, 2010 drawn from the Taiwan Economic Journal. The empirical results show that (1) the return from the day applying to TWSE or OTC to the last trading day on emerging stock market is 47.01%. (2)The IPOs market adjusted return on the first trading day is 58.37%. (3) The performance of IPO stocks listed on OTC is better than stocks listed on TWSE after their offering. We also observed the stock price before listing to test price discovery function of emerging stock market. Our research show that stocks price on emerging stock market has appropriately reacted before listing. Emerging stock market has price discovery mechanism.

知訊者與非知訊者資訊不對稱之議題在學術殿堂一直廣為學者所研究討論，且各國證管機關為了維持證券市場公平性、保護非知訊者權益並且維持股票市場的穩定運作，適度的資訊揭露以維持證券市場的公平性一直都是各國證券交易所重視的政策目標。 是故，本研究利用代理人基人工股票市場來探討資訊揭露對於金融市場之影響。在此架構下之交易者皆已有限理性方式來呈現。他們是以遺傳規劃(genetic programming)之方式來學習並修正他們對於未來之金融市場之預期。在透過即時的模擬價格之資訊揭露，我們嘗試探討此資訊揭露之金融政策措施對於市場之波動性、市場之流動性之影響。 / The topic of asymmetric information between the informed traders and uninformed traders has been widely discussed by researchers in academics. To maintain the fairness of securities market, an appropriate information disclosure is quite important for authorities of securities regulation to protect the rights and interests of uninformed traders, and to maintain the operations of securities market stable. Based on these reasons, we construct an agent-based artificial stock market to investigate how information disclosure affects a financial market. In this framework of artificial stock market, all traders are characterized by bounded rationality. The traders are able to learn and adjust their predictions of financial market by means of a genetic programming algorithm. We try to understand how market transparency affects the volatility and the liquidity of a securities market.

A stochastic model for the dynamics of a limit order book is evaluated and tested on empirical data. Arrival of limit, market and cancellation orders are described in terms of a Markovian queuing system with exponentially distributed occurrences. In this model, several key quantities can be analytically calculated, such as the distribution of times between price moves, price volatility and the probability of an upward price move, all conditional on the state of the order book. We show that the exponential distribution poorly fits the occurrences of order book events and further show that little resemblance exists between the analytical formulas in this model and the empirical data. The log-normal and Weibull distribution are suggested as replacements as they appear to fit the empirical data better.

Em um contexto de demandas sociais tendencialmente crescentes, uma das alternativas para o aumento da arrecadação de receitas pelo Estado reside no manejo de aplicações financeiras. Os investimentos financeiros estatais, a rigor, já acontecem, mas nem sempre o objetivo claro e explícito de obtenção de resultados financeiramente interessantes e, eventualmente ou mesmo por isso , sob gestão economicamente ineficiente. Às vezes, até se enxerga o foco na obtenção de rendimentos relevantes na ação estatal, mas sem uma disciplina específica, o que pode abrir espaço a uma gestão de ativos desqualificada ou mesmo fraudulenta, com sérios prejuízos aos cofres públicos e, em situações extremas, ampliação ainda maior das despesas públicas. O objetivo desta tese, portanto, é reconhecer que nem sempre o Estado atua na economia com propósito interventivo e que, na qualidade de investidor institucional vale dizer, de ente que tem o dever de proceder aos investimentos e às aplicações financeiras que digam com as melhores práticas de administração dos ativos públicos , precisa atuar sob o jugo de normas jurídicas claras, que permitam ao Estado ampliar suas receitas dentro de limites razoáveis de exposição a risco financeiro e disponibilizem aos órgãos de fiscalização e controle da Administração Pública as ferramentas necessárias para, também quanto a esse aspecto, aferir a eficiência da ação estatal. Para tanto, têm-se como pressupostos o anacronismo da resistência cultural às aplicações financeiras dos entes da Administração Pública e a noção de que quaisquer ferramentas de obtenção de receitas pelo Estado estão sujeitas a algum grau de risco. Com base nas bem-sucedidas experiências nacionais e internacionais, será possível concluir, ao final, que é admissível, do ponto de vista constitucional e legal, a ação do Estado como investidor nos mercados financeiro e de capitais e que é viável a formulação de parâmetros gerais para a disciplina jurídica do Estado investidor. / In a context of growing social demands, financial investments become one of the alternatives for the State to increase its revenues. State investments, as a matter of fact, already do happen, but not always with the clear and explicit objective of obtaining financially interesting earnings, often due economically inefficient management. Sometimes it is possible to see in government investments some focus on obtaining relevant income, but not under a specific regulation, which can lead to an unqualified or even fraudulent management that may cause serious damage to the exchequer and, in extreme situations, expansion of the government spending. Hence the intent of this thesis is to acknowledge that the State does not always act in the economy with regulatory purposes and that, as an institutional investor i.e., an organization which has the duty of making financial investments in accordance to the best practices in public asset management , it must be framed by clear legal rules, which should allow the State to maximize its revenues within reasonable limits of financial risk exposure and the oversight and control agencies to assess the State efficiency and compliance. It is assumed that the cultural resistance to state financial investments is anachronistic as well as every state means of obtaining revenues is subject to some level of financial risk. Based on well succeeded experiences in Brazil and abroad, it will be possible to conclude, in the end, that it is constitutionally and legally admissible that the State acts as an investor in financial and stock markets and that it is possible to suggest some standards on legal regulation for this issue.

Em um contexto de demandas sociais tendencialmente crescentes, uma das alternativas para o aumento da arrecadação de receitas pelo Estado reside no manejo de aplicações financeiras. Os investimentos financeiros estatais, a rigor, já acontecem, mas nem sempre o objetivo claro e explícito de obtenção de resultados financeiramente interessantes e, eventualmente ou mesmo por isso , sob gestão economicamente ineficiente. Às vezes, até se enxerga o foco na obtenção de rendimentos relevantes na ação estatal, mas sem uma disciplina específica, o que pode abrir espaço a uma gestão de ativos desqualificada ou mesmo fraudulenta, com sérios prejuízos aos cofres públicos e, em situações extremas, ampliação ainda maior das despesas públicas. O objetivo desta tese, portanto, é reconhecer que nem sempre o Estado atua na economia com propósito interventivo e que, na qualidade de investidor institucional vale dizer, de ente que tem o dever de proceder aos investimentos e às aplicações financeiras que digam com as melhores práticas de administração dos ativos públicos , precisa atuar sob o jugo de normas jurídicas claras, que permitam ao Estado ampliar suas receitas dentro de limites razoáveis de exposição a risco financeiro e disponibilizem aos órgãos de fiscalização e controle da Administração Pública as ferramentas necessárias para, também quanto a esse aspecto, aferir a eficiência da ação estatal. Para tanto, têm-se como pressupostos o anacronismo da resistência cultural às aplicações financeiras dos entes da Administração Pública e a noção de que quaisquer ferramentas de obtenção de receitas pelo Estado estão sujeitas a algum grau de risco. Com base nas bem-sucedidas experiências nacionais e internacionais, será possível concluir, ao final, que é admissível, do ponto de vista constitucional e legal, a ação do Estado como investidor nos mercados financeiro e de capitais e que é viável a formulação de parâmetros gerais para a disciplina jurídica do Estado investidor. / In a context of growing social demands, financial investments become one of the alternatives for the State to increase its revenues. State investments, as a matter of fact, already do happen, but not always with the clear and explicit objective of obtaining financially interesting earnings, often due economically inefficient management. Sometimes it is possible to see in government investments some focus on obtaining relevant income, but not under a specific regulation, which can lead to an unqualified or even fraudulent management that may cause serious damage to the exchequer and, in extreme situations, expansion of the government spending. Hence the intent of this thesis is to acknowledge that the State does not always act in the economy with regulatory purposes and that, as an institutional investor i.e., an organization which has the duty of making financial investments in accordance to the best practices in public asset management , it must be framed by clear legal rules, which should allow the State to maximize its revenues within reasonable limits of financial risk exposure and the oversight and control agencies to assess the State efficiency and compliance. It is assumed that the cultural resistance to state financial investments is anachronistic as well as every state means of obtaining revenues is subject to some level of financial risk. Based on well succeeded experiences in Brazil and abroad, it will be possible to conclude, in the end, that it is constitutionally and legally admissible that the State acts as an investor in financial and stock markets and that it is possible to suggest some standards on legal regulation for this issue.

The aim of the diploma is to introduce provide information about financial system of Russia. It includes a description and classification of Russian financial markets, development of the whole system and describe a current financial position during the crisis. Diploma also includes Regulation and Supervision part, which is relatively important due to a present situation in the financial world. In terms of practical part basing on technical and fundamental analyses the author tends to forecast the probable future trend of development of the Russian Trade System RTS. The diploma is made for a wide range of prospective readers, who even might not be interested in Finance.

Economic bubbles are playing an increasingly significant role in the current global economy. We believe these bubbles are to a certain extent dominating the real economy, and, therefore, research based on this specific economic phenomenon is becoming increasingly popular and important. The focus of this master's thesis is based upon analysis of stock price bubbles. This thesis contains author analyzed historical cases representative of stock price bubbles; summarizations of their traditional features; common factors causing their formation; and reasons leading to their bursting. Solutions to the dilemma of stock price bubbles are discussed in depth, and emphasis is placed upon clearly deciphering different theoretical approaches regarding this phenomenon-not only from the efficient market hypothesis viewpoint but also from the perspective of behavioral finance. The research contains testing and measuring methodologies of stock price bubbles, and the author's view concerning them is strongly supported by the results within the empirical data-testing chapter. Upon reading, one can expect to achieve a basic overview of this forefront science.

Cette thèse étudie le lien entre les caractéristiques des conseils d’administration des banques acquéreuseset la performance boursière à court terme de celles-ci, analysée grâce à la méthodologie d’étude d’événement.L’objectif étant de vérifier si la structure des conseils contribue à l’atténuation des conflits d’intérêts àl’occasion des opérations de fusions-acquisitions (F&A) et crée, par conséquent, de la valeur. Deux effets ontété mis en avant. Le premier suppose une influence directe de chacune des caractéristiques du conseil sur lesrendements anormaux de l’acquéreur ; tandis que le second, introduit l’effet médiateur de la prime de contrôlepayée, en considérant que la structure du conseil influence le pouvoir de négociation de ses membres et leurengagement dans l’intérêt des actionnaires. Pour ces deux effets, nous contrôlons certains déterminants de laperformance relatifs à la transaction et aux banques impliquées.Nos résultats indiquent que les marchés financiers ont des attentes vis-à-vis des conseils lors de cesopérations, car nous avons relevé une incidence favorable sur les rendements anormaux de la présence depersonnalités extérieures en proportion significative au conseil de l’acquéreur et de l’absence de dualité dedirection dans celui-ci. Par ailleurs, en contrôlant le choix de la méthode de paiement, nous avons égalementrelevé que l’utilisation du cash est fortement associé à des rendements positifs pour l’acquéreur. / This thesis analyzes the relationship between Board characteristics of acquiring Banks and short termStock Market reactions, measured with the Event Study Methodology. We examine if Board structure helps tolower conflict of interests during Mergers and Acquisitions, and creates Shareholder value. Two effects areanalysed. The first one supposes a direct influence of Board characteristics on the acquirer’s abnormal returns.The second one introduces a mediating effect of the premium, considering that Board structure affects itsmembers’ commitment. For both effects, we control some performance determinants relative to transactionand involved banks.Our results indicate that Financial Markets expect that Boards play an important role in acquisitions. Wefind a favourable impact of outside dominated Boards and the absence of duality on the acquirer's abnormalreturns. In addition, by controlling the method of payment, we obtain a significant and positive correlationbetween use of cash and acquirer's returns.