This dissertation consists of 3 essays that examine the impact of electronic screen trading in futures markets. The research provides empirical evidence on increasingly significant issues given the rapid global advances in technology used in securities markets. Each essay addresses the scarcity of conclusive research in order to aid researchers, regulators, exchange policy makers and systems builders as they confront issues related to electronic trading systems.

Le thème central de cette thèse est l'analyse économique du marché du haut débit et plus particulièrement l'économie des infrastructures de l'information. Les infrastructures de l'information désignent des réseaux numériques qui permettent de délivrer des services de communication et d'information exigeant des débits de transmission de données de plus en plus élevés. Cette thèse s'articule autour de trois problématiques. La première partie est consacrée à la demande de services haut débit et plus particulièrement aux inégalités d'accès à ces services. À partir d'une base de données regroupant des informations sur plus de 5600 ménages français, on propose deux analyses économétriques de la fracture numérique. La seconde partie est consacrée aux politiques de dégroupage. Tout d'abord, à partir d'une analyse économétrique portant sur 14 pays européens, on cherche à déterminer si le niveau du tarif de dégroupage a influencé positivement ou négativement la pénétration du haut débit. Ensuite, on propose un modèle dans lequel le concept de l'échelle d'investissement développé par Cave (2006) est analysé formellement. La troisième partie est consacrée aux exclusivités de distribution de contenus audiovisuels. À partir d'un modèle théorique, on analyse dans quels cas une firme verticalement intégrée, présente sur le marché du haut débit et également sur celui de la distribution de contenus, est incitée à réserver l'exclusivité de la distribution de son contenu à ses abonnées haut débit.

This thesis contributes to the econometric literature in two ways. Firstly, it introduces a new multivariate count model that presents advances in several aspects. Our multivariate time series count model can deal with issues of discreteness, overdispersion (variance greater than the mean) and both cross- and serial correlation, all at the same time. We follow a fully parametric approach and specify a marginal distribution for the counts where, conditionally on past observations the means follow a vector autoregressive process (VAR). This enables to attain improved inference on coefficients of exogenous regressors relative to the static Poisson regression, while modelling the serial correlation in a flexible way. The method is also innovative in the use of copulas, which builds the dependence structure between variables with given marginal distributions. This makes it possible to model the contemporaneous correlation between individual series in a very flexible way. Secondly, this thesis introduces a new approach to estimate the multivariate reduced rank regressions when the normality assumption is not satisfied. We propose to use the copula tool to generate multivariate distributions and, we show that this method can be applied in multivariate settings. In terms of financial literature, this thesis provides two contributions. Firstly, with our multivariate count model we analyze diverse market microstructure issues about the submission of different types of orders by traders on stock markets. With this model, we can fully take into account the interactions between submissions of the various types of orders, which represent an advantage with respect to univariate models such as the autoregressive conditional duration model. Secondly, it contributes to portfolio research proposing a new dynamic optimal portfolio allocation model in a Value-at-Risk setup. This model allows for time varying skewness and kurtosis of portfolio distributions and the model parameters are estimated by weighted maximum likelihood in an increasing window setup. This last property allows us to have more accurate portfolio recommendations in terms of the amount to invest in the risk-free interest rate and in the risky portfolio.

This thesis analyzes the timing issue related to informed trades under two different market frameworks. Firstly, the issue under the competitive market framework is analyzed. In financial market, a widely accepted assumption that competitive informed traders elect to trade immediately upon receiving their private information is now questioned. We propose a competitive rational expectations model to demonstrate that under some situations informed traders tend to trade late on their information because of the fear of adverse effect on prices from their informed trades. This phenomenon from delayed informed trades leads to the following: Price volatility will increase and adjacent price changes may exhibit positive serial correlation. Secondly, we turn to the alternative framework, i.e., a market microstructure framework. A large number of market microstructure models had already investigated the timing issue of informed trades. Most of them found that the competition among informed traders will make the informed traders incline to trade early than late on their information and the market therefore becomes more efficient. We develop a market microstructure model with competitive, risk averse informed traders and uninformed market makers. It is found that when the mass of informed traders is larger or the precision of private information is higher, the market becomes less efficient, that is, prices will delay revealing the private information and the market will postpone becoming liquid. Our results stand in contrast to those of other market microstructure models simply because informed traders in our model choose to trade late on their information. In conclusion, the thesis has proved that the timing to trade on their information is an important consideration for informed traders to determine their trading strategy maximizing their expected utility. Since this issue is seldom discussed in the previous literature, I deeply believe that there are many works to be done followed this work.

This dissertation is divided into an introductory chapter and four essays. Chapter one discusses the importance of the study and describes the development and growth of the market as well. The first part (Chapters 2 & 3) examines stock returns behaviour and trading activity around earnings announcements. The second part (Chapters 4 & 5) examines price impact asymmetry and the price effects of block trades in the market microstructure context. Each essay addresses some aspects of market microstructure and stock returns behaviour in order to aid researchers, investors and regulators to understand a market which lacks research coverage. The research provides empirical evidence on issues such as the efficiency of the market, information asymmetry, liquidity and price impact of block trades. In first part of the thesis, event study and regression analysis were used to measure the price reaction around earnings announcements and to examine trading activity, information asymmetry and liquidity. In second part the determinants of the price impact of block trades were examined with regard to trade size, market condition and time of the day effects using transaction data. Liquidity and information asymmetry issues of block trades were also studied in this part.

A complex system is one with many parts, whose behaviors are strongly dependent on each other. There are two interesting questions about complex systems. One is to understand how to recover the true structure of a complex system from noisy data. The other is to understand how the system interacts with its environment. In this thesis, we address these two questions by studying two distinct complex systems: dynamic systems and market microstructure. To address the first question, we focus on some nonlinear dynamic systems. We develop a novel Bayesian statistical method, Gaussian Emulator, to estimate the parameters of dynamic systems from noisy data, when the data are either fully or partially observed. Our method shows that estimation accuracy is substantially improved and computation is faster, compared to the numerical solvers. To address the second question, we focus on the market microstructure of hidden liquidity. We propose some statistical models to explain the hidden liquidity under different market conditions. Our statistical results suggest that hidden liquidity can be reliably predicted given the visible state of the market. / Statistics

The global foreign exchange market is the largest financial market with turnover in this market often outstripping the GDP of countries in which they are located. The dynamics in the foreign exchange market, especially price dynamics, have huge implications for financial asset values, financial returns and volatility in the international financial system. It is therefore an important area of study. Exchange rates have often departed significantly from the level implied by fundamentals and exhibit excessive volatility. This reality creates a role for central bank intervention in this market to keep the rate in line with economic fundamentals and the overall policy mix, to stabilize market expectations and to calm disorderly markets. Studies that attempt to measure the effectiveness of intervention in the foreign exchange market in terms of exchange rate trends and volatility have had mixed results. This, in many cases, reflects the unavailability of data and the weaknesses in the empirical frameworks used to measure effectiveness. This thesis utilises the most recent data available and some of the latest methodological advances to measure the effectiveness of central bank intervention in the foreign exchange markets of a variety of countries. It therefore makes a contribution in the area of applied empirical methodologies for the measurement of the dynamics of intervention in the foreign exchange market. It demonstrates that by using high frequency data and more robust and appropriate empirical methodologies central bank intervention in the foreign exchange market can be effective. Moreover, a framework that takes account of the interactions between different central bank policy instruments and price dynamics, the reaction function of the central bank, different states of the market, liquidity in the market and the profitability of the central bank can improve the effectiveness of measuring the impact of central bank policy in the foreign exchange market and provide useful information to policy makers.

This dissertation consists of 3 essays that examine the impact of electronic screen trading in futures markets. The research provides empirical evidence on increasingly significant issues given the rapid global advances in technology used in securities markets. Each essay addresses the scarcity of conclusive research in order to aid researchers, regulators, exchange policy makers and systems builders as they confront issues related to electronic trading systems.

O propósito dessa pesquisa é estudar a relação entre a revelação de informação corporativa e o comportamento de uma seleção de empresas com fortes políticas de revelação de informação e alto grau de capitalização do Mercado Acionário da Colômbia, para o ano 2014. Mediante esse estudo, é analisada a microestrutura utilizando informação de alta frequência e notícias corporativas publicadas na plataforma de Bloomberg Professional Services. A metodologia de análise para prover evidência da relação foi o estudo de eventos, testando a significância da diferença entre as médias e medianas pré-evento e pós-evento de alguns indicadores de liquidez, retorno e volatilidade. Os resultados permitem concluir que a disseminação de informação tem um impacto sobre a liquidez e a volatilidade do mercado. Percebe-se que no período posterior à publicação das notícias, o tamanho dos bid-ask spreads e a volatilidade do midquote diminui, os investidores negociam em média menores volumes e quantidade de operações e submetem menor quantidade de intenções de compra e venda. / The purpose of this investigation is to study the relationship between corporate disclosure and the behavior of a selection of companies, with strong disclosure policies and high market capitalization ratio of the Colombian Stock Market, for the entire year 2014. The idea of this investigation is to analyze the market microstructure using high frequency data and corporate information publicized through the Bloomberg professional services platform. The estimation technique to provide evidence of the relationship is the event study, testing the significance of the difference between the pre-event and post-event average and median of some indicators of return, liquidity and volatility. The results prove that the disemintation of information impact the market liquidity and volatility. It is noticed that in the post-event window, bid-ask spreads and volatility of the midquote decreases, traders negociate on average lower volums and number of transactions and submit fewer buy and sell order intentions.

This thesis consists of three essays examining the impact and consequences of the trading behaviour of a finely disaggregated category of investors in an electronic limit order book equity market, the Malta Stock Exchange (MSE). The three essays in market microstructure are closely related and examine how investor heterogeneity impacts the informational content of the limit order book, the informational content of individual trades, the price impact of investor trades, the aggressiveness of order submission strategies and the price discovery process within such a market. The first essay investigates the role of the financial intermediary in the price discovery process in a limit order market. We address this issue by analysing the trades of brokers within the Malta Stock Exchange by comparing the profitability of their individual trades and the impact of these trades on the price discovery process. The results of a Weighted Price Contribution methodology indicate that more active brokers that dominate the market in terms of volume and amount traded account for a significant portion of the price discovery process. We also find that the level of profitability of these brokers is directly proportional to the amount of volume traded and their relative share in the price discovery process. This appears to rule out the possibility of manipulative trades by these brokers in order to influence profitabilityThe second essay examines the price impact of the order flow emanating from finely disaggregated classes of investor with the aim of determining whether detectable differences exist in the extent to which orders emanating from particular groups of investors impact on the evolution of stock prices. On the aggregate stock level, results indicate price impact is inversely related to liquidity and as such the price impact of trades is of a higher magnitude and significance in stocks that are less liquid. Significantly, we find that stocks with higher liquidity and trading volume adjust quickly to price changes and the cumulative impact is realised earlier for these stocks. Similarly, for investor classes, our results show that the magnitude and significance of individual price impact increases as liquidity of the stocks declines, showing that as liquidity increases in the order book, the impact of information asymmetry begins to diminish. Institutional investors consistently have the highest significant impact on the evolution of prices across all the stocks. The final essay examines how investors structure their order submission choice in response to changes in the limit order book and market conditions (such as order depth, volatility, returns, and height of the limit order book). We identify 7 distinct investor classes who differ in their trading requirement and the information set available to them, and as such we expect that these investors will adopt different strategies to maximise their trades. The results show variability in the submission strategies adopted by investors as trade sides changes from buy to sell trades. It also indicate that investors have to balance between execution risk, the timely use of private information and the risk of being picked-off by other informed investors. In analysing the varied responses of these investors, we find that the order submission strategies adopted is most responsive to the risk of non-execution.