nÃo hà / The study involves the application of time series techniques to investigate the phenomenon of the War Tax generated by the financial and tax benefits granted in a general way by the Federal District and municipalities seeking new investments for the development of their region in order to leverage through the collection of the Tax on Circulation of Goods and Services Transport and Communications - ICMS. The investigation includes the three major economies of the Northeast: CearÃ, Pernambuco and Bahia. From monthly data for the Industrial Production Average - PIM and the total collection of VAT between 2004 and 2010 models were estimated vector autoregressive econometric and tests of Granger causality and that although there is a causal relationship between the amount produced in the three economies, the argument does not hold a Tax War. / O estudo consiste na aplicaÃÃo de tÃcnicas de sÃries temporais para investigar o fenÃmeno da Guerra Fiscal gerado pelos os benefÃcios fiscais e financeiros concedidos de forma generalizada pelos Estados, Distrito Federal e MunicÃpios que buscam novos investimentos para o desenvolvimento de sua regiÃo com o intuito de alavancar a arrecadaÃÃo atravÃs do Imposto sobre a CirculaÃÃo de Mercadorias e ServiÃos de Transportes e ComunicaÃÃes â ICMS. A investigaÃÃo compreende as trÃs principais economias da regiÃo Nordeste: CearÃ, Pernambuco e Bahia. A partir de dados mensais para a ProduÃÃo Industrial MÃdia â PIM e para a arrecadaÃÃo total do ICMS entre 2004 e 2010 foram estimados modelos vetoriais autorregressivos e realizados testes economÃtrico como de causalidade de Granger que muito embora exista uma relaÃÃo de causalidade entre o montante produzido nas trÃs economias, nÃo se sustenta o argumento de Guerra Fiscal.

O nexo causal entre desenvolvimento financeiro e crescimento econômico vem ganhando destaque na literatura desde o início dos anos 1990. As principais linhas teóricas nessa área buscam demonstrar qual a significância da relação e o sentido da causalidade, se houver. Causalidade unidirecional no sentido do desenvolvimento financeiro para o crescimento econômico, bicausalidade entre ambos, e causalidade reversa, no sentido do crescimento para o desenvolvimento financeiro, são as principais hipóteses testadas nas pesquisas empíricas. O presente trabalho de tese tem por objetivo avaliar o nexo causal entre crédito (como um indicador do desenvolvimento financeiro) e crescimento no setor agropecuário brasileiro. O crédito rural como proporção do PIB agropecuário cresceu substancialmente desde meados da década de 90, passando de 15,44% em 1996 para 65,24% em 2014. Ao longo do período 1969-2014, a razão média anual entre crédito rural e PIB agropecuário foi de 43,87%. No mesmo período, o produto agropecuário cresceu em média 3,76% ao ano. Questiona-se se no mercado rural o crédito causa o crescimento agropecuário, se ocorre causalidade reversa ou se se opera a hipótese de bicausalidade. Para avaliar o nexo causal entre essas duas variáveis econômica foram empregados quatro procedimentos metodológicos: teste de causalidade de Granger em uma representação VAR com a abordagem de Toda e Yamamoto, teste de causalidade de Granger em um modelo FMOLS (Fully Modified OLS), teste de causalidade de Granger em um modelo ARDL (Autoregressive-Distributed Lag) e teste de causalidade de Granger no domínio da frequência, com o uso do método de Breitung e Candelon. Os resultados mostram de forma uniforme a presença de causalidade unidirecional do crédito rural para o crescimento do produto agropecuário. Causalidade reversa, no sentido do crescimento agropecuário para o crédito rural, não foi detectada de forma significativa em nenhum dos quatro métodos empregados. A não detecção de bicausalidade pode ser uma evidência do impacto da forte política de subsídio governamental ao crédito rural. A decisão do Governo quanto ao montante anual de crédito rural disponível a taxas de juros subsidiadas pode estar impedindo que o desempenho do setor, medido pela sua taxa de crescimento, exerça uma influência significativa na dinâmica do crédito rural. Os resultados também abrem a possibilidade a testar a hipótese de exogeneidade do crédito rural, o que seria uma extensão direta dos resultados obtidos. / The finance and growth nexus has gained great attention in economic literature since the early 1990s. The main theoretical lines in this area try to demonstrate if the relationship between financial development and economic growth is significant, and what is the direction of causality, if any. Causality running from financial development to economic growth, bi-causality, and reverse causality, from finance to economic growth, are the main hypotheses tested in empirical research. This thesis aims to assess the causal link between credit (as an indicator of financial development) and growth in Brazilian rural sector. The ratio of rural credit to agricultural GDP has grown substantially since the mid-90s, going from 15.44% in 1996 to 65.24% in 2014. Over the period 1969-2014, the ratio of rural credit to agriculture GDP was 43.87% on average. In the same period, agricultural GDP grew 3.76% on average per year. We question whether there is causality running from rural credit to agricultural growth, if reverse causality occurs or if the bi-causality hypothesis operates in Brazilian rural market. To evaluate the causal link between these two economic variables, four methodological procedures were employed: Granger causality test in a VAR framework using Toda and Yamamoto approach, Granger causality test in a FMOLS (Fully Modified OLS) model, Granger causality test in an ARDL (Autoregressive Distributed-Lag) model and Granger causality test in the frequency domain, using Breitung and Candelon method. The results uniformly show the presence of causality running from rural credit to agricultural growth. Reverse causality, from agricultural growth to rural credit, was not significantly detected in any of the four methods. The failure to detect bi-causality may be an evidence of the impact of government\'s subsidy policy on rural credit. The government\'s decisions on the annual amount of rural credit available at subsidized interest rates may be preventing the sector\'s performance, as measured by its growth rate, to significantly influence the dynamics of rural credit. The results also open the possibility to test the exogeneity hypothesis of rural credit.

O objetivo desta dissertação será analisar a dinâmica do processo de integração financeira entre o mercado acionário brasileiro e o norte americano. Buscaremos identificar a relação de interdependência entre os dois mercados acionários ao longo do tempo por meio de testes de cointegração, e de causalidade de Granger com rolling windows, e através de um modelo de correção de erros estimado por meio do filtro de Kalman. Por fim, verificaremos se as séries temporais obtidas nos procedimentos iterativos possuem relação com a volatilidade ou quantidade de negócios dos contratos analisados. Evidenciamos nesta dissertação que a relação de integração financeira observada apresenta caráter variável ao longo do tempo. Isso vale tanto para a relação de cointegração, quanto para a relação de causalidade de Granger entre as séries temporais observadas. Evidenciamos também que a volatilidade das séries apresenta uma relação positiva e significativa com a relação de cointegração observada através dos testes de cointegração por meio de rolling windows. / The aim of this dissertation is to analyze the dynamics of financial integration between the Brazilian and the North American stock market. We will seek to identify the interdependence relationship between the two stock markets over time using rolling cointegration tests, rolling Granger causality tests, and estimating an error correction model using Kalman filter. Finally, we look if the time series obtained in the iterative procedures are related to volatility or quantity of trades from the contracts. We show in this dissertation that the financial integration relationship observed has a time varying character over time. This goes for both the cointegration relationship, and for the Granger causality relationship between the observed time series. We show also that the volatility of the time series has a positive and significant relationship with the cointegration relationship observed through the rolling cointegration tests.

This work analyzes an interrelationship between stock indices S&P 500, FTSE 100, DAX, HSI, Nikkei, BSI and PX in a time period from September 2004 till March 2010. Such an interrelationship has already been examined and a dominating position of American indices has been found. This influence was stronger during a financial crisis. Because the examined time period covers both financial crisis and the period before, the work studies their interrelationship in the whole period and at the end in the time period before financial crisis. The influence of one stock index on the other can be cause by several factors: (i) dominance of influencing stock index, (ii) efficient market and (iii) financial crisis. As the reaction of stock index is evoked from new information, the intention of this work is to take into account nonsychronous trading of stocks exchanges. Therefore I explored those exchange stocks closing earlier than the others start in two ways by respecting the time lag and by non-respecting the time lag. The interrelationship between the indices was modeled with help of VAR models and proved by Granger causality test.

The aim of this study was to investigate the influence of free information on the Internet on decreasing sales of printed newspapers. I tested the main hypothesis that the increase in Internet daily visits in the previous period has an impact on the sales of the printed journal in the following period . Another researched phenomenon was the influence of previous rising visitors of web news on subsequent revenue from advertising in print version. These effects I researched on -month and quarterly data in panel of eight czech dailies for the period from 2006 to 2012. The result is that we could not confirm the effect of Granger causality between web pages and his dailies itself nor on a monthly or quarterly basis. When it comes to examining the impact of Internet visits to newspapers revenue from advertising, on the contrary, here we confirmed Granger causality on quarterly data from past revenues from advertising to the current Internet visits . This means that the Internet visits will decrease when there is increased advertising income of newspapers in the previous quarter, which is , however, difficult to interpret in economic terms . The main benefit of this work is that the effect of preceding of webiste visits and newspaper circulations was not confirmed.

In the recent years, there has been growing talk of investing in commodities in the financial markets. In the past, the commodity markets served for purposes of the producers and the end-users of commodities. With gradual innovation of the financial markets in the 19th and 20th century the modern commodity markets evolved and became more standardized. This process was accompanied by the increasing interest of financial speculators. In contrast with the commercial participants, the goal of these new investors in the commodity markets is not to hedge against adverse changes in commodity prices but to profit on the price movements of commodities. The inflow of this group was intensified by the development of new financial instruments enabling these investors to enter the commodity markets. It is undisputable that speculators have positive effect on the markets, by providing liquidity and lowering transaction costs. What remains to be answered is the real effect which the speculators have on the commodity prices, and if their action does not create distortion in the commodity prices. The price development on the commodity markets during the recent financial crisis gives strong arguments in the hands of those accusing the speculators of the negative impact on the commodity prices, which sometimes lead to creation of price bubbles. The goal of this thesis will be the analysis of the effect of speculators on the commodity markets, and if this prejudice is justified.

This research addressed two main issues that have become evident in studies of interstate cooperation. The first issue has to do with the relationship between cooperation and conflict. Can they be represented on a single, uni-dimensional continuum, or are they better represented by two theoretically and empirically separable dimensions? Granger causality tests were able to clarify the nature of cooperative events. The second issue is related to factors that might facilitate or discourage cooperation with other countries as a foreign policy tool. Factors used to explain cooperation and conflict include domestic variables, which have not been fully accounted for in previous empirical analyses. It is hypothesized that economic variables, such as inflation rates, GDP, and manufacturing production indices affect the likelihood of cooperative event occurrences. The effect of political dynamics, such as electoral cycles, support rates and national capability status, can also affect the possibility of cooperative foreign policies. The domestic factors in panel data was tested with Feasible Generalized Least Square (FGLS) in order to take care of heteroscedasticity and autocorrelations in residuals. The individual case analysis used linear time series analysis.

Redes complexas aplicadas em sinais de atividade cerebral mostraram a presença de anormais padrões de conectividade em pacientes que sofriam com doenças e outros distúrbios psiquiátricos. Logo, passou-se a cogitar a influência dessas estruturas na causa desses problemas e o que leva ao desenvolvimento desses padrões anormais. Do ponto de vista teórico, vários trabalhos mostram como a topologia de uma rede pode alterar um processo que se sustenta nela, por exemplo o modo como a rede influencia a propagação de falhas de um sistema, a sincronização ou processos de dispersão. Nesse sentido, o objetivo do trabalho é caracterizar as redes funcionais de pacientes durante episódios de crises de epilepsia, fazendo um paralelo entre a estrutura dessas redes e os processos dinâmicos envolvidos na crise, em especial a sincronização. Para isto, dados reais foram analisados e as redes inferidas em um primeiro passo. Depois, simulações de sistemas artificiais usando os parâmetros obtidos das análises, mostram o impacto dessas redes nos processos dinâmicos. Os resultados apontam para estruturas que podem aumentar a sincronização e a influência do modo de acoplamento nesses sistemas. / Complex networks applied to brain activity signals show the presence abnormal of connectivity patterns in patients suffering with diseases and others psychiatric disorders. From this, some authors began to question the influence of these structures in the cause of these problems and how it leads to the development of these abnormal patterns. From a theoretical point of view, several studies show how the topology of a network can change a process that maintains it, for example how a network influences the propagation of a system failure, synchronization or diffusion processes. In this sense, the objective of this study is to characterize the functional networks of patients during episodes of seizures, making a parallel between the structure of these networks and the dynamic processes involved in the epilepsy, in particular the synchronization. For this, real data were analyzed and the inferred networks in a first step. And then, artificial simulations using the parameters obtained from the analysis were employed to show the impact of these networks in dynamic processes. The results indicate structures that can enhance the synchronization and the influence of the coupling mode on these systems.

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

Soil moisture influences the water and energy cycles of terrestrial environments, and thus plays an important climatic role. However, the behavior of soil moisture at large scales, including its impact on atmospheric processes such as precipitation, is not well characterized. Satellite remote sensing allows for indirect observation of large-scale soil moisture, but validation of these data is complicated by the difference in scales between remote sensing footprints and direct ground-based measurements. To address this problem, a method, based on information theory (specifically, mutual information), was developed to determine the useful information content of satellite soil moisture records using precipitation observations. This method was applied to three soil moisture datasets derived from Advanced Microwave Scanning Radiometer for EOS (AMSR-E) measurements over the contiguous U.S., allowing for spatial identification of the algorithm with the least inferred error. Ancillary measures of biomass and topography revealed a strong dependence between algorithm performance and confounding surface properties. Next, statistical causal identification methods (i.e. Granger causality) were used to examine the link between AMSR-E soil moisture and the occurrence of next day precipitation, accounting for long term variability and autocorrelation in precipitation. The probability of precipitation occurrence was modeled using a probit regression framework, and soil moisture was added to the model in order to test for statistical significance and sign. A contrasting pattern of positive feedback in the western U.S. and negative feedback in the east was found, implying a possible amplification of drought and flood conditions in the west and damping in the east. Finally, observations and simulations were used to demonstrate the pitfalls of determining causality between soil moisture and precipitation. It is shown that ignoring long term variability and precipitation autocorrelation can result in artificial positive correlation between soil moisture and precipitation, unless explicitly accounted for in the analysis. In total, this dissertation evaluates large-scale soil moisture measurements, outlines important factors that can cloud the determination of land surface-atmosphere hydrologic feedback, and examines the causal linkage between soil moisture and precipitation at large scales.