Housing prices are of crucial importance in financial stability management. The severe financial crises that originated in the housing market in the US and subsequently spread throughout the world highlighted the crucial role that the housing market plays in preserving financial stability. After the severe housing market crash, many financial institutions in the US suffered from high default rates, severe liquidity shortages, and even bankruptcy. Against this background, researchers have sought to use econometric models to capture and forecast prices of homes. Available empirical research indicates that nonlinear models may be suitable for modelling price cycles. Accordingly, this thesis focuses primarily on using nonlinear models to empirically investigate cyclical patterns in housing prices. More specifically, the content of this thesis can be summarised in three essays which complement the existing literature on price modelling by using nonlinear models. The first essay contributes to the literature by testing the ability of regime switching models to capture and forecast house prices. The second essay examines the impact of banking factors on house price fluctuations. To account for house price characteristics, the regime switching model and generalised autoregressive conditionally heteroscedastic (GARCH) in-mean model have been used. The final essay investigates the effect of structural breaks on the unit root test and shows that a time-varying GARCH in-mean model can be used to estimate the housing price cycle in the UK.

In the present paper we study switching state space models from a Bayesian point of view. For estimation, the model is reformulated as a hierarchical model. We discuss various MCMC methods for Bayesian estimation, among them unconstrained Gibbs sampling, constrained sampling and permutation sampling. We address in detail the problem of unidentifiability, and discuss potential information available from an unidentified model. Furthermore the paper discusses issues in model selection such as selecting the number of states or testing for the presence of Markov switching heterogeneity. The model likelihoods of all possible hypotheses are estimated by using the method of bridge sampling. We conclude the paper with applications to simulated data as well as to modelling the U.S./U.K. real exchange rate. (author's abstract) / Series: Forschungsberichte / Institut für Statistik

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.

In the present paper we discuss Bayesian estimation of a very general model class where the distribution of the observations is assumed to depend on a latent mixture or switching variable taking values in a discrete state space. This model class covers e.g. finite mixture modelling, Markov switching autoregressive modelling and dynamic linear models with switching. Joint Bayesian estimation of all latent variables, model parameters and parameters determining the probability law of the switching variable is carried out by a new Markov Chain Monte Carlo method called permutation sampling. Estimation of switching and mixture models is known to be faced with identifiability problems as switching and mixture are identifiable only up to permutations of the indices of the states. For a Bayesian analysis the posterior has to be constrained in such a way that identifiablity constraints are fulfilled. The permutation sampler is designed to sample efficiently from the constrained posterior, by first sampling from the unconstrained posterior - which often can be done in a convenient multimove manner - and then by applying a suitable permutation, if the identifiability constraint is violated. We present simple conditions on the prior which ensure that this method is a valid Markov Chain Monte Carlo method (that is invariance, irreducibility and aperiodicity hold). Three case studies are presented, including finite mixture modelling of fetal lamb data, Markov switching Autoregressive modelling of the U.S. quarterly real GDP data, and modelling the U .S./U.K. real exchange rate by a dynamic linear model with Markov switching heteroscedasticity. (author's abstract) / Series: Forschungsberichte / Institut für Statistik

In the present paper we discuss the problem of estimating model likelihoods from the MCMC output for a general mixture and switching model. Estimation is based on the method of bridge sampling (Meng and Wong, 1996), where the MCMC sample is combined with an iid sample from an importance density. The importance density is constructed in an unsupervised manner from the MCMC output using a mixture of complete data posteriors. Whereas the importance sampling estimator as well as the reciprocal importance sampling estimator are sensitive to the tail behaviour of the importance density, we demonstrate that the bridge sampling estimator is far more robust in this concern. Our case studies range from computing marginal likelihoods for a mixture of multivariate normal distributions, testing for the inhomogeneity of a discrete time Poisson process, to testing for the presence of Markov switching and order selection in the MSAR model. (author's abstract) / Series: Report Series SFB "Adaptive Information Systems and Modelling in Economics and Management Science"

O objetivo geral deste trabalho é testar se a informação contida em dados de microestrutura de mercado contribui para uma melhor explicação do comportamento dos preços dos títulos negociados na BMF&BOVESPA. O primeiro ensaio testa a hipótese de que o volume gera informação sobre o movimento dos preços quando os traders possuem informações diferentes sobre o comportamento dessa variável. Em uma abordagem de microestrutura de mercado, os traders não informados observam apenas as estatísticas diárias de preço e volume, e os traders informados conhecem o comportamento dos preços e volumes tick-by-tick. Aplicando o algoritmo do tick-test, os traders informados observam o volume de ordens de compras e vendas diárias. O teste empírico é feito utilizando modelos markov-switching, e os resultados revelam que os traders informados apresentam estimações melhores. No segundo ensaio, buscam-se evidências de que traders informados preferem atuar no mercado de opções pela possibilidade de alavancar seus ganhos. O objetivo é identificar se o volume no mercado de opções revela o comportamento dos preços das ações. Os resultados obtidos, utilizando opções de PETR4 e VALE5, corroboram a hipótese que o volume no mercado de opções não transmite informação sobre o comportamento do preço da ação. O terceiro ensaio utiliza dados tick-by-tick para estimar a probabilidade de informação privilegiada (PIN) para ações do IBRX. O PIN é uma proxy para informação privada e é incorporado ao método de Fama e French (1993) para separar os portfolios e explicar seus retornos. A combinação do PIN com as variáveis valor de mercado e índice book-to-market possibilita, para alguns portfolios, aumento do retorno e diminuição do risco. A significância das variáveis na explicação dos retornos é testada utilizando modelos de markov-switching. Os resultados permitem concluir que o PIN é um fator importante na explicação dos retornos dos portfolios. / The general objective is to test whether the information contained in data of microstructure market contributes to a better explanation of the behavior of stock prices negotiated in BMF&BOVESPA. The first essay tests the hypothesis that volume generates information on price movements when traders have different information on the behavior of this variable. In a model of market microstructure, non-informed traders observe only the daily statistics on price and volume, while informed traders know the behavior of tick-by-tick prices and volumes. Applying the tick-test algorithm, informed traders observe the volume of buy orders and daily sales. The empirical test is carried out by using markov-switching models, and the results reveal that informed traders show better estimates. In the second essay, we look for evidence that informed traders prefer to trade in options market due to its possibility of leveraging their revenue. The objective is to identify whether volume in the options market is revealing of the behavior of stock prices. The results obtained using options from PETR4 and VALE5 concur to the hypothesis that volume in options market does not transmit information on the behavior of stock price. The third essay makes use of tick-by-tick data to estimate the probability of privileged information (PIN) to IBRX stocks. PIN is a proxy to privilege information and is incorporated to Fama French (1993) method to separate portfolios and explain their returns. The combination of PIN with variables of market value and book-to-market index allows some portfolios to increase return and diminish risk. The significance of these variables in explaining returns is tested using markov-switching methods. The results demonstrate that PIN is an important factor in explaining portfolio returns.

O objetivo geral deste trabalho é testar se a informação contida em dados de microestrutura de mercado contribui para uma melhor explicação do comportamento dos preços dos títulos negociados na BMF&BOVESPA. O primeiro ensaio testa a hipótese de que o volume gera informação sobre o movimento dos preços quando os traders possuem informações diferentes sobre o comportamento dessa variável. Em uma abordagem de microestrutura de mercado, os traders não informados observam apenas as estatísticas diárias de preço e volume, e os traders informados conhecem o comportamento dos preços e volumes tick-by-tick. Aplicando o algoritmo do tick-test, os traders informados observam o volume de ordens de compras e vendas diárias. O teste empírico é feito utilizando modelos markov-switching, e os resultados revelam que os traders informados apresentam estimações melhores. No segundo ensaio, buscam-se evidências de que traders informados preferem atuar no mercado de opções pela possibilidade de alavancar seus ganhos. O objetivo é identificar se o volume no mercado de opções revela o comportamento dos preços das ações. Os resultados obtidos, utilizando opções de PETR4 e VALE5, corroboram a hipótese que o volume no mercado de opções não transmite informação sobre o comportamento do preço da ação. O terceiro ensaio utiliza dados tick-by-tick para estimar a probabilidade de informação privilegiada (PIN) para ações do IBRX. O PIN é uma proxy para informação privada e é incorporado ao método de Fama e French (1993) para separar os portfolios e explicar seus retornos. A combinação do PIN com as variáveis valor de mercado e índice book-to-market possibilita, para alguns portfolios, aumento do retorno e diminuição do risco. A significância das variáveis na explicação dos retornos é testada utilizando modelos de markov-switching. Os resultados permitem concluir que o PIN é um fator importante na explicação dos retornos dos portfolios. / The general objective is to test whether the information contained in data of microstructure market contributes to a better explanation of the behavior of stock prices negotiated in BMF&BOVESPA. The first essay tests the hypothesis that volume generates information on price movements when traders have different information on the behavior of this variable. In a model of market microstructure, non-informed traders observe only the daily statistics on price and volume, while informed traders know the behavior of tick-by-tick prices and volumes. Applying the tick-test algorithm, informed traders observe the volume of buy orders and daily sales. The empirical test is carried out by using markov-switching models, and the results reveal that informed traders show better estimates. In the second essay, we look for evidence that informed traders prefer to trade in options market due to its possibility of leveraging their revenue. The objective is to identify whether volume in the options market is revealing of the behavior of stock prices. The results obtained using options from PETR4 and VALE5 concur to the hypothesis that volume in options market does not transmit information on the behavior of stock price. The third essay makes use of tick-by-tick data to estimate the probability of privileged information (PIN) to IBRX stocks. PIN is a proxy to privilege information and is incorporated to Fama French (1993) method to separate portfolios and explain their returns. The combination of PIN with variables of market value and book-to-market index allows some portfolios to increase return and diminish risk. The significance of these variables in explaining returns is tested using markov-switching methods. The results demonstrate that PIN is an important factor in explaining portfolio returns.

O objetivo geral deste trabalho é testar se a informação contida em dados de microestrutura de mercado contribui para uma melhor explicação do comportamento dos preços dos títulos negociados na BMF&BOVESPA. O primeiro ensaio testa a hipótese de que o volume gera informação sobre o movimento dos preços quando os traders possuem informações diferentes sobre o comportamento dessa variável. Em uma abordagem de microestrutura de mercado, os traders não informados observam apenas as estatísticas diárias de preço e volume, e os traders informados conhecem o comportamento dos preços e volumes tick-by-tick. Aplicando o algoritmo do tick-test, os traders informados observam o volume de ordens de compras e vendas diárias. O teste empírico é feito utilizando modelos markov-switching, e os resultados revelam que os traders informados apresentam estimações melhores. No segundo ensaio, buscam-se evidências de que traders informados preferem atuar no mercado de opções pela possibilidade de alavancar seus ganhos. O objetivo é identificar se o volume no mercado de opções revela o comportamento dos preços das ações. Os resultados obtidos, utilizando opções de PETR4 e VALE5, corroboram a hipótese que o volume no mercado de opções não transmite informação sobre o comportamento do preço da ação. O terceiro ensaio utiliza dados tick-by-tick para estimar a probabilidade de informação privilegiada (PIN) para ações do IBRX. O PIN é uma proxy para informação privada e é incorporado ao método de Fama e French (1993) para separar os portfolios e explicar seus retornos. A combinação do PIN com as variáveis valor de mercado e índice book-to-market possibilita, para alguns portfolios, aumento do retorno e diminuição do risco. A significância das variáveis na explicação dos retornos é testada utilizando modelos de markov-switching. Os resultados permitem concluir que o PIN é um fator importante na explicação dos retornos dos portfolios. / The general objective is to test whether the information contained in data of microstructure market contributes to a better explanation of the behavior of stock prices negotiated in BMF&BOVESPA. The first essay tests the hypothesis that volume generates information on price movements when traders have different information on the behavior of this variable. In a model of market microstructure, non-informed traders observe only the daily statistics on price and volume, while informed traders know the behavior of tick-by-tick prices and volumes. Applying the tick-test algorithm, informed traders observe the volume of buy orders and daily sales. The empirical test is carried out by using markov-switching models, and the results reveal that informed traders show better estimates. In the second essay, we look for evidence that informed traders prefer to trade in options market due to its possibility of leveraging their revenue. The objective is to identify whether volume in the options market is revealing of the behavior of stock prices. The results obtained using options from PETR4 and VALE5 concur to the hypothesis that volume in options market does not transmit information on the behavior of stock price. The third essay makes use of tick-by-tick data to estimate the probability of privileged information (PIN) to IBRX stocks. PIN is a proxy to privilege information and is incorporated to Fama French (1993) method to separate portfolios and explain their returns. The combination of PIN with variables of market value and book-to-market index allows some portfolios to increase return and diminish risk. The significance of these variables in explaining returns is tested using markov-switching methods. The results demonstrate that PIN is an important factor in explaining portfolio returns.

A presente dissertação de conclusão de mestrado tem por objetivo contribuir com a literatura existente que versa acerca da estimação da Taxa de Câmbio Real (RER) através de fundamentos econômicos. O objetivo deste trabalho é utilizar o instrumental teórico de modelos com mudança de regime (Markov Switching) aplicado sobre os fundamentos que determinam a RER em um modelo de Cointegração. O modelo teórico utilizado para a estimação foi o proposto por Montiel (1999), modelo este que é mais indicado para países em desenvolvimento, para o período de 1994 até 2005. Os resultados obtidos na estimação da Taxa de Câmbio Real foram contundentes em demonstrar que havia três regimes distintos (definidos como sendo regimes de estabilidade, transição e risco extremo) na determinação da RER, indicando que havia uma relação não linear entre está última e os fundamentos econômicos. Verificou-se ainda que a magnitude e os sinais dos parâmetros dos fundamentos estimados para cada regime distinto eram diferentes, sugerindo que a RER reagia de maneira distinta a choques nos fundamentos econômicos de acordo com o regime que a economia se encontrava. Os coeficientes obtidos nas estimações foram utilizados para estimar uma Taxa de Câmbio de Equilíbrio, sendo possível identificar os desvios (misalignments) da taxa observa com relação à taxa estimada a parti r de 1994. / The present dissertation aims to contribute with the studies over Real Exchange Rate in Brazil and the impact of the economic fundamentals on its determination. The main purpose of the dissertation is to use the Markov Switching framework over the fundamentals in the estimation of the Real exchange Rate to the period between 1994 and 2005, using a model based on Montiel (1999), which is more appropriate to developing countries. The results show strong evidences that there are different regimes (interpreted as stability, transition and extremely risk), which can be understood as a non linear relationship between the Real Exchange Rate and the fundamentals. In other words, it was possible to show that the impact of the fundamentals over the Real Exchange Rate is submitted to three different regimes, where the magnitude and signal of their coefficients are different in each regime. The parameters of the model were used to estimate an Equilibrium Real Exchange Rate, which was possible to demonstrate the misalignments after 1994.

A presente dissertação de conclusão de mestrado tem por objetivo contribuir com a literatura existente que versa acerca da estimação da Taxa de Câmbio Real (RER) através de fundamentos econômicos. O objetivo deste trabalho é utilizar o instrumental teórico de modelos com mudança de regime (Markov Switching) aplicado sobre os fundamentos que determinam a RER em um modelo de Cointegração. O modelo teórico utilizado para a estimação foi o proposto por Montiel (1999), modelo este que é mais indicado para países em desenvolvimento, para o período de 1994 até 2005. Os resultados obtidos na estimação da Taxa de Câmbio Real foram contundentes em demonstrar que havia três regimes distintos (definidos como sendo regimes de estabilidade, transição e risco extremo) na determinação da RER, indicando que havia uma relação não linear entre está última e os fundamentos econômicos. Verificou-se ainda que a magnitude e os sinais dos parâmetros dos fundamentos estimados para cada regime distinto eram diferentes, sugerindo que a RER reagia de maneira distinta a choques nos fundamentos econômicos de acordo com o regime que a economia se encontrava. Os coeficientes obtidos nas estimações foram utilizados para estimar uma Taxa de Câmbio de Equilíbrio, sendo possível identificar os desvios (misalignments) da taxa observa com relação à taxa estimada a parti r de 1994. / The present dissertation aims to contribute with the studies over Real Exchange Rate in Brazil and the impact of the economic fundamentals on its determination. The main purpose of the dissertation is to use the Markov Switching framework over the fundamentals in the estimation of the Real exchange Rate to the period between 1994 and 2005, using a model based on Montiel (1999), which is more appropriate to developing countries. The results show strong evidences that there are different regimes (interpreted as stability, transition and extremely risk), which can be understood as a non linear relationship between the Real Exchange Rate and the fundamentals. In other words, it was possible to show that the impact of the fundamentals over the Real Exchange Rate is submitted to three different regimes, where the magnitude and signal of their coefficients are different in each regime. The parameters of the model were used to estimate an Equilibrium Real Exchange Rate, which was possible to demonstrate the misalignments after 1994.