The great recession of 2008-2010 has impacted the world's economy, which has begun with the sub-prime crisis in the US subprime mortgage market and subsequently spread to the world economy through the contagion effect. Moreover, the influence of the recession on the other nation's economy has been markedly differentiated, depending on their vulnerability to financial system problems (credit crunch, liquidity inflows). Some countries were hit very hard and experienced a drop in GDP, rising unemployment, etc. However, other countries were affected slightly, or the direct effects on them were not visible. Similarly, Central and Eastern Europe (CEE) countries have experienced a very differentiated course of the crisis. As a result of the recession, economic policymakers have tightened financial supervision and regulatory frameworks. This study adopts seven Eastern and Central European Countries (Poland, including Czech Republic, Hungary, Romania, Slovakia, Lithuania and Bulgaria) and analyzes the effect of recession on the stock market of the selected countries. The relevant leading stock market indices of individual countries are adopted as an indicator of the development of the financial market. Monthly data for January 2000-May 2021 is used, and this period is further divided into two samples...

Orientador: Marco Eustáquio de Sá / Resumo: As relações entre vigor de sementes e desempenho em campo ainda não estão totalmente esclarecidas, sendo questionável se estes efeitos se estendem até estádios fenológicos mais avançados e se afetam a produção da cultura. Diante disso, objetivou-se avaliar os efeitos na produção de mudas e de plantas de couve-flor com uso de doses de produto à base de Bacillus subtilis no tratamento de sementes. O estudo foi realizado no ano de 2019, sendo o delineamento experimental de blocos casualizados (campo) e delineamento inteiramente casualizado (análises laboratoriais) em esquema fatorial 2 x 5 x 2 com quatro repetições. O primeiro fator foi cultivar: Sharon e Barcelona, os tratamentos foram constituídos do tratamento de sementes com produto à base de B. subtilis (FMT001) em cinco doses (0, 100, 200, 300 e 400 mL por 10 kg de sementes) e o terceiro fator foi localidade: Ilha Solteira/SP e Junqueirópolis/SP. Foram avaliados o vigor das sementes e as características produtivas da cultura: massas da parte aérea, raiz e inflorescência, número de folhas, diâmetro da inflorescência, produtividade e teor de macronutrientes das inflorescências. Os resultados mostraram que as doses de 200 e 400 mL favorecem o aumento da porcentagem de plântulas fortes dos cultivares Barcelona e Sharon, respectivamente. Em Ilha Solteira, o cultivar Barcelona expressou incremento na massa de parte aérea e de raiz nas doses de 100, 200 e 300 mL, em Junqueirópolis, o cultivar Sharon apresentou aumento na massa da... (Resumo completo, clicar acesso eletrônico abaixo) / Mestre

Orientador: Giuseppina Pace Pereira Lima / Resumo: O cozimento além de facilitar a digestibilidade e a palatabilidade dos vegetais, pode alterar a biodisponibilidade de micronutrientes. As couves-flores são normalmente consumidas após processamento térmico e apresentam níveis elevados de compostos bioativos que influenciam na saúde humana, especialmente na prevenção as doenças crônicas. Estes compostos possuem atividade antioxidante que confere proteção e auxilia o organismo humano a eliminar os radiacias livres, componentes centrais das regulações metabólicas induzidas por doenças crônicas. Desta forma, o objetivo deste estudo foi avaliar o efeito do tempo e tipo de cozimento (fervura, vapor e micro-ondas) sobre as características bioquímicas de quatro genótipos de couve-flor colorida (‘Verde di Macerata’, ‘Cheddar’, ‘Forata’ e ‘Graffiti’). Em um primeiro momento, foi determinado o perfil físico-químico das couves-flores coloridas. Os floretes foram submetidos aos tratamentos térmicos por 5 e 10 min e após foram realizadas as análises físico-químicas. O processamento em ebulição resultou em perdas significativas de sólidos solúveis totais e carboidratos solúveis totais, diferentemente dos métodos onde foram utilizadas menores quantidades de água para o processamento das inflorescências (i.e., micro-ondas e vapor). Os métodos a vapor e micro-ondas resultaram em valores superiores de sólidos solúveis, independente do genótipo analisado. O cozimento dos floretes em ebulição reduziu significativamente os teores da maioria dos co... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The cooking process, besides facilitating the digestibility and palatability of vegetables, can alter the bioavailability of micronutrients. The cauliflowers are usually consumed after a thermal process and present high levels of bioactive compounds that positively affect the human health, particularly in chronic disease prevention. The compounds possess antioxidant activity that provides protection and assists the human organism in eliminating free radicals, central compounds in metabolic regulations induced by chronic diseases. Thus, the objective of this study was to evaluate the effect of time and cooking procedure (boiling, steaming and microwaving) over the biochemical characteristics of four genotypes of colored cauliflowers (‘Verde di Macerata’, ‘Cheddar’, ‘Forata’ e ‘Gradffiti’). Firstly, the physicochemical profile of the colored cauliflowers was determined. The cauliflowers were subjected to the thermal processes for 5 and 10 minutes and physicochemical analysis were performed. The boiling process resulted in significant losses of total soluble solids and total soluble carbohydrates, unlike the methods where smaller amounts of water were used for processing the inflorescences (i.e., microwaving and steaming). The steaming and microwaving methods resulted in superior values of soluble solids, independently of the analyzed genotype. The cooking of the inflorescences by boiling reduced significantly the contents of the majority of the analyzed chemical compounds (titr... (Complete abstract click electronic access below) / Doutor

The objective of this thesis is to develop alternative forms of Dynamic Stochastic General Equilibrium (DSGE) models for forecasting the South African economy and, in turn, compare them with the forecasts generated by the Classical and Bayesian variants of the Vector Autoregression Models (VARs). Such a comparative analysis is aimed at developing a small-scale micro-founded framework that will help in forecasting the key macroeconomic variables of the economy. The thesis consists of three independent papers. The first paper develops a small-scale DSGE model based on Hansen's (1985) indivisible labor Real Business Cycle (RBC) model. The results suggest that, compared to the VARs and the Bayesian VARs, the DSGE model produces large out-of-sample forecast errors. In the basic RBC framework, business cycle fluctuations are purely driven by real technology shocks. This one-shock assumption makes the RBC models stochastically singular. In order to overcome the singularity problem in the RBC model developed in the first paper, the second paper develops a hybrid model (DSGE-VAR), in which the theoretical model is augmented with unobservable errors having a VAR representation. The model is estimated via maximum likelihood technique. The results suggest DSGE-VAR model outperforms the Classical VAR, but not the Bayesian VARs. However, it does indicate that the forecast accuracy can be improved alarmingly by using the estimated version of the DSGE model. The third paper develops a micro-founded New-Keynesian DSGE (NKDSGE) model. The model consists of three equations, an expectational IS curve, a forward-looking version of the Phillips curve, and a Taylor-type monetary policy rule. The results indicate that, besides the usual usage for policy analysis, a small-scale NKDSGE model has a future for forecasting. The NKDSGE model outperforms both the Classical and Bayesian variants of the VARs in forecasting inflation, but not for output growth and the nominal short-term interest rate. However, the differences of the forecast errors are minor. The indicated success of the NKDSGE model for predicting inflation is important, especially in the context of South Africa - an economy targeting inflation. / Thesis (PhD (Economics))--University of Pretoria, 2008. / Economics / unrestricted

The 2008/9 financial crisis intensified the search for realistic return models, that capture real market movements. The assumed underlying statistical distribution of financial returns plays a crucial role in the evaluation of risk measures, and pricing of financial instruments. In this dissertation, we discuss an empirical study on the evaluation of the traditional portfolio risk measures, and option pricing under the hybrid Brownian motion model, developed by Shaw and Schofield. Under this model, we derive probability density functions that have a fat-tailed property, such that “25-sigma” or worse events are more probable. We then estimate Value-at-Risk (VaR) and Expected Shortfall (ES) using four equity stocks listed on the Johannesburg Stock Exchange, including the FTSE/JSE Top 40 index. We apply the historical method and Variance-Covariance method (VC) in the valuation of VaR. Under the VC method, we adopt the GARCH(1,1) model to deal with the volatility clustering phenomenon. We backtest the VaR results and discuss our findings for each probability density function. Furthermore, we apply the hybrid model to price European style options. We compare the pricing performance of the hybrid model to the classical Black-Scholes model. / Dissertation (MSc)--University of Pretoria, 2017. / National Research Fund (NRF), University of Pretoria Postgraduate bursary and the General Studentship bursary / Mathematics and Applied Mathematics / MSc / Unrestricted

The research aims to investigate the relationship between economic freedom, political freedom and economic growth. The Arab Spring placed renewed interest on the topic of freedom, yet current economic conditions seemingly contradicted the established theory. The largest free economies were being outperformed by those with less political and economic freedom.Three objectives were specified to answer the research question. The first objective aimed to determine the association between economic freedom, political freedom and economic growth, for which Spearman’s correlation was used. The second objective aimed to investigate causal relationships between the variables, for which Granger’s causality was employed. The third objective aimed to examine complex relationships between the variables, for which vector autoregression was used.Economic growth was weakly correlated with the independent variables. Civil liberties, political rights and economic freedom, however, had strong correlations with each other. Economic freedom and economic growth had bi-directional Granger-causality. Political rights Granger-caused economic freedom whilst civil liberties Granger-caused political rights and economic freedom. Using vector autoregression, the model consisting of economic growth, economic freedom and civil liberties had the greatest explanatory power towards economic growth. Existing theory therefore remains valid: political freedom enhances economic freedom, which, in turn, enhances economic growth.The relationship between economic freedom, political freedom and economic growth / Dissertation (MBA)--University of Pretoria, 2012. / Gordon Institute of Business Science (GIBS) / unrestricted

Orientador: Jose Roberto Sanches Mantovani / Banca: Rubén Augusto Romero Lázaro / Banca: Marcos Julio Rider Flores / Banca: Roberto de Souza Salgado / Banca: Ivan Nunes da Silva / Resumo: Nesta pesquisa tem-se por objetivo resolver de forma descentralizada os problemas de despacho e planejamento ótimo de fontes de potência reativa (POVAr) no contexto de sistemas com múltiplas áreas ou regiões interligadas. Na solução descentralizada o problema de otimização é dividido em subproblemas associados a cada área. Os operadores regionais resolvem, coordenadamente, subproblemas de menor dimensão utilizando os dados de rede de suas áreas e informações de fronteira associadas às linhas de interligação. Para conseguir este objetivo, esta pesquisa está dividida em 4 etapas principais: i) formalizar os problemas de planejamento e de despacho ótimo de potência reativa, ii) determinar a viabilidade da aplicação de duas diferentes técnicas de decomposição para resolver o problema de despacho ótimo de potência reativa multi-área, iii) propor várias metodologias para lidar com variáveis discretas no problema de despacho e planejamento ótimo de potência reativa em SEP multi-área, e iv) propor um método de análise multi-área para o problema de planejamento ótimo de reativos sob contingências. Para mostrar o funcionamento e a eficiência das metodologias propostas, vários sistemas multi-áreas são utilizados: o sistema IEEE RTS-96 com 3 e 5 áreas e um sistema interligado conformado por 3 áreas do sistema IEES RTS-96 e duas áreas do sistema IEEE de 118 barras / Abstract: This research has been aimed at solving the decentralized problem of reactive power sources optimal planning (VAr planning) in the context of systems with multiple interconnected areas. In the decentralized solution, the optimization problem is divided into subproblems associated with each area. The regional operators solve, coordinately, smaller subproblems using the network data from their areas and border information associated with the tie-lines. To propose a method to the decentralized VAr planning problem, four basic aspects are covered. First, formalize the problems of planning and optimal dispatch of reactive power. Second, the viability of applying two different decomposition techniques to solve the problem of optimal reactive power dispatch, as well as its convergence properties, are analyzed. Third, several techniques for handling discrete variables in the decentralized VAr planning problem are proposed and tested. Fourth, a decentralized approach to the VAr planning under contingency in multi-area systems is provided. To show the operation and efficiency of the proposed methodologies, several multi-area systems are used: the IEEE RTS-96 system with 3 and 5 areas and an interconnected system formed by three areas of the IEEE RTS-96 and two areas of the IEEE 118 bus system / Doutor

Real estate industry plays a significant role in high speed of economic development in China. However, with increasingly high housing price and scare land resources, real estate development is caught in a vicious circle. A large number of families could not afford their housing while housing prices have no trend to decrease which leads to huger gap between the rich and the poor and causes indirectly instability of society. Therefore, creating a healthy and stable real estate investment market is extremely urgent. The purpose of the thesis is to research the relationship between leading index of macro economy prosperity and real estate investment based on the reality. We found that leading indicator Granger causes real estate investment while real estate investment Granger causes leading indicator at the same time. Based on that, this paper also forecasts the real estate investment with VAR models in the following 7 years which was proved to a circle of real estate market. In the light of our research, some target suggestions are pointed out at last.

The continuous integration infrastructure (CI servers) is commonly used as a shared test environment due to the need for collaborative and distributive development for the software products under growing scale and complexity in recent years. To ensure the stability of the CI servers, with the help of the constantly recorded measurement data of the servers, fault prediction is of great interest to software development companies. However, the lack of fault data is a typical challenge in learning the fault patterns directly. Alternatively, predicting the standard observations that represent the normal behavior of the CI servers can be viewed as an initial step toward fault prediction. Faults can then be identified and predicted by studying the difference between observed data and predicted standard data with enough fault data in the future. In this thesis, a long short-term memory (LSTM), a bidirectional LSTM (BiLSTM), and a vector autoregressive (VAR) models are developed. The models are compared on both one-step-ahead prediction and iteratively long-range prediction up to 60 steps (corresponds to 15 minutes for the CI servers analyzed in the thesis). To account for the uncertainties in the predictions, the LSTM-based models are trained to estimate predictive variance. The prediction intervals obtained are then compared with the VAR model. Moreover, since there are many servers in the CI infrastructure, it is of interest to investigate whether a model trained on one server can represent other servers. The investigation is carried out by applying the one-step-ahead LSTM model on a set of other servers and comparing the results. The LSTM model performs the best overall with only slightly better than the VAR model, whereas the BiLSTM model performs the worst in the one-step-ahead prediction. When taking the uncertainties into account, the LSTM model seems to estimate the assumed distribution the best with the highest log-likelihood. For long-range prediction, the VAR model surprisingly performs the best across almost all range lengths. Lastly, when applying the LSTM one-step-ahead model on the other servers, the performance differs from server to server, which indicates that it is less likely to achieve competitive performance when applying the same model on all servers.

Real estate industry plays a significant role in high speed of economic development in China. However, with increasingly high housing price and scare land resources, real estate development is caught in a vicious circle. A large number of families could not afford their housing while housing prices have no trend to decrease which leads to huger gap between the rich and the poor and causes indirectly instability of society. Therefore, creating a healthy and stable real estate investment market is extremely urgent. The purpose of the thesis is to research the relationship between leading index of macro economy prosperity and real estate investment based on the reality. We found that leading indicator Granger causes real estate investment while real estate investment Granger causes leading indicator at the same time. Based on that, this paper also forecasts the real estate investment with VAR models in the following 7 years which was proved to a circle of real estate market. In the light of our research, some target suggestions are pointed out at last.