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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Analýza sezónnosti v českém stavebnictví / Analysis of Seasonality in the Czech Construction

Šimpach, Ondřej January 2010 (has links)
The output of the National economy of the Czech Republic is conditioned by a sum of important factors. There are sectors, which increased power during the last two decades, mainly due to expansion of modern technologies and knowledge workers. One of this is Construction. Construction is specific to its position in the economy and in particular is characterized by the greatest seasonality ever. However, this is not a problem for statistical analysis, rather a benefit. Modern approaches allow us to analyze seasonal fluctuations. From selected data we are able to construct evolutionary forecasts. The work will be performed for the most important indicators in the Czech Construction. The outcome of the paper will be conditional forecasts of these indicators. It will also make analyze of the relationship between these indicators and other variables that might affected it. The work is practical application of stochastic modeling approach by Box and Jenkins, augmented by more modern approaches, such as verification of Granger causality and co-integration and testing of seasonal unit roots by Hylleberg et al.
42

Caracterização e modelagem da atividade eletrofisiológica em pacientes com epilepsia / Characterization and modeling of electrophysiological activity in patients with epilepsy

Rodrigues Neto, Abner Cardoso 20 April 2016 (has links)
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.
43

O nexo causal entre crédito rural e crescimento do produto agropecuário na economia brasileira / The credit and growth nexus in Brazilian agricultural sector

Moura, Fábio Rodrigues de 28 April 2016 (has links)
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.
44

Role hollywoodského filmového průmyslu v průběhu hospodářského cyklu první dekády 21. století / The role of the Hollywood film industry during the business cycle in the first decade of the 21 century

Hanáčková, Michaela January 2011 (has links)
The aim of the thesis is to examine the relationship between the course of the business cycle and the cycle of the Hollywood film industry. In the introductory section are raised theoretical approaches to the economic cycle, which seeks to clarify the causes of decline of economic activity, and compares the different recommendations. The next section is devoted to clarify the specifics of the film industry and provides a better understanding of non-transparent processes within the industry. The analytical part tests the causal relationship between the economic situation of the individual and the Hollywood studios, based on a sample of 90 observations using the Granger causality test and VAR model. Prior to empirical testing is provided a comprehensive analysis of the industry cycles from the inception to the present and is compared to the economic activity of the country. Finally, the confirmation or refutation of dependence and the result is compared with economic theory.
45

Causalidade entre as taxas de crescimento dos paÃses desenvolvidos e emergentes / Causality enters the taxes of growth of the developed and emergent countries

JoÃo Francisco de Souza Filho 08 May 2008 (has links)
AtravÃs da utilizaÃÃo de instrumentais estatÃsticos e economÃtricos para a anÃlise de sÃries temporais, buscou-se verificar as relaÃÃes entre as taxas de crescimento dos paÃses desenvolvidos e emergentes. Para tanto, utilizou-se de uma amostra contendo a taxa real de crescimento econÃmico desses paÃses no perÃodo de 1970-2007. Com base nesse estudo, verificou-se que existe causalidade, no sentido Granger, do crescimento econÃmico dos paÃses desenvolvidos em direÃÃo aos paÃses emergentes. A funÃÃo de resposta a impulsos mostrou que a resposta dos paÃses emergentes a choques no crescimento dos paÃses desenvolvidos foi a mais significativa e duradoura. / Through the use of statistical and econometric instrumentals for the analysis of time series, this work aims to verify the relationships between the economic growth rate of developed and emergent countries. For so much, it was used of a sample containing the real economic growth rate of those countries in the period of 1970-2007. With base in this study, it was verified that causality exists, in the sense of Granger, of the economic growth rate of the countries developed towards the emerging countries. The impulse response function showed that the answer of the emerging countries to impacts in the economic growth of the developed countries was the most significant and durable.
46

Investigating the Long- and the Short-Run Diversification Potential of REITs for Private Investors / En studie av REITs långsiktiga och kortsiktiga diversifieringspotential för privatinvesterare

Granath, Klara, Carlsson, Charlotta January 2019 (has links)
Real estate is commonly viewed as a good diversification tool since the real estate market cycle exhibit low correlations to other asset classes. Moreover, Real Estate Investment Trusts (REITs) have become increasingly popular in the past decades since this investment form offers private investors a convenient way of diversifying stock portfolios with real estate. Some studies investigating the within-country diversification potential of REITs and stocks have been performed. These studies generally suggest poor diversification potential. Hence, we investigate the international diversification potential of REITs from Europe, Asia Pacific and the US for private investors holding European stocks from 2007 to 2019. For Europe and Asia Pacific, REIT markets with different maturity levels are included since emerging and developed REIT markets might have different characteristics affecting the diversification potential. We also examine which market leads which in terms of changes in returns. Moreover, the diversification potential of REITs may depend on the investment horizon, hence the long- and short-run perspectives for private investors are examined. The lesson learned from the Global Financial Crises and European Debt Crisis is that abnormal market conditions may change the behavior of assets on the financial markets, and significantly affect portfolio behavior. Hence, diversification potential in relation to crises is also considered. The methods employed are Johansen’s cointegration, Granger non-causality and DCC-GARCH. Our findings suggest long- and short-run diversification potential of international REITs for European stocks. Cross-regional combinations of REITs and stocks generally offer better diversification potential than within-regional combinations, and emerging REIT markets are preferred over their developed counterparts due to lower conditional correlations. Moreover, changes in stock market returns lead changes in REIT market returns, indicating that stock markets react more quickly to new information on the market. Long- and short-run diversification potential still exists during the crises although increased conditional correlations suggest higher interdependence in this period. However, there is no trend of increasing conditional correlations over the whole sample, suggesting the abnormal market conditions during the financial turmoil did not permanently change the diversification potential of REITs in stock portfolios.
47

股價報酬與經濟成長關係的跨國實證

林碧雯 Unknown Date (has links)
股價報酬與經濟成長的關係雖有許多理論上的支持,但進行跨國比較時仍未有理論能夠分辨,因而提出三個問題進行研究,想探討的也就是常聽到的這兩句話「股市是經濟的櫥窗」、「股市是經濟的先行指標」是否成立。   針對所提出問題的理論基礎先做清楚的釐清,發現消費與投資是影響經濟成長的重要因素;從制度面進行新的推論,找出「財產權保護」、「內部交易」兩變數做為分類的標準;將預計實證的結果分為「健全的股市制度」與「未成熟的股市制度」兩大類陳述。本文以股價指數(SI)代表金融面、工業生產(IP)代表實質面、財產權保護與內部交易兩制度變數做為分類的依據,針對二十四個國家進行跨國比較,研究期間最早從1981年1月到2000年12月,在此採用最一般化的模型以進行跨國比較,採用 Granger Causality 之因果關係檢定,將實證結果分為【第一階段】、【第二階段】、【第三階段】依序探討。   雖然並無直接的證據支持預計實證的結果,但經由三階段的分析仍可發現股價報酬與經濟成長的關係強弱、領先程度應該和市場健全發展有直接關係,雖然內部交易與財產權保護兩制度變數無法捕捉健全市場的全貌,但仍扮演一定的角色。唯有股價報酬與經濟成長的關係較強,才不容易形成泡沫危機;也唯有股價報酬領先經濟成長的時間較長,才有可能從政策面著手緩和景氣循環的波動,因此提供一個健全發展的金融環境非常重要。
48

Essays in time series econometrics and forecasting with applications in marketing

Ribeiro Ramos, Francisco Fernando, fr1960@clix.pt January 2007 (has links)
This dissertation is composed of two parts, an integrative essay and a set of published papers. The essay and the collection of papers are placed in the context of development and application of time series econometric models in a temporal-axis from 1970s through 2005, with particular focus in the Marketing discipline. The main aim of the integrative essay is on modelling the effects of marketing actions on performance variables, such as sales and market share in competitive markets. Such research required the estimation of two kinds of time series econometric models: multivariate and multiple time series models. I use Autoregressive Integrated Moving Average (ARIMA) intervention models and the Pierce and Haugh statistical test to model the impact of a single marketing instrument, mainly price promotions, to measure own and cross-short term sales effects, and to study asymmetric marketing competition. I develop and apply Vector AutoRegressive (VAR) and Bayesian Vector AutoRegressive (BVAR) models to estimate dynamic relationships in the market and to forecast market share. Especially, BVAR models are advantageous because they contain all relevant dynamic and interactive effects. They accommodate not only classical competitive reaction effects, but also own and cross-market share brand feedback effects and internal decision rules and provided substantively useful insights into the dynamics of demand. The integrative essay is structured in four main parts. The introduction sets the basic ideas behind the published papers, with particular focus on the motivation of the essay, the types of competitive reaction effects analysed, an overview of the time series econometric models in marketing, a short discussion of the basic methodology used in the research and a brief description of the inter-relationships across the published papers and structure of the essay. The discussion is centred on how to model the effects of marketing actions at the selective demand or brand level and at the primary demand or product level. At the brand level I discuss the research contribution of my work on (i) modelling promotional short-term effects of price and non-price actions on sales and market share for consumer packaged goods, with no competition, (ii) how to measure own and cross short-term sales effects of advertising and price, in particular, cross-lead and lag effects, asymmetric sales behaviour and competition without retaliatory actions, in an automobile market, (iii) how to model the marketing-mix effectiveness at the short and long-term on market shares in a car market, (iv) what is the best method to forecast market share, and (v) the study of causal linkages at different time horizons between sales and marketing activity for a particular brand. At the product or commodity level, I propose a way to model the flows of tourists that come from different origins (countries) to the same country-destination as market segments defining the primary demand of a commodity - the product
49

The relationship between advertising and household loans

Sahlin, Daniel, Sjögren, Gustav January 2008 (has links)
Advertising expenditures are increasing on a yearly basis. An interesting question emerges from this: What are the macroeconomic effects of increasing advertising spending? Does the aggregate consumption increase or does it only rearrange consumption between different products and markets? The relationship between advertising and consumption was found in the literature, this relationship was further developed and the relationship between advertising and household loans emerged as an interesting subject. An econometric analysis method was used to test the relationship between the aggregated advertising expenditure and the aggregated sum of household loans, in order to investigate whether advertising spending cause changes in the use of total household loans in Sweden. The research did not conclude that aggregate advertising spending causes changes in the use of total household loans in Sweden. However, evidence was found which supports that household loans cause advertising expenditures. An implication of the findings is that the relationship between aggregated sum of household loans and advertising might be as interrelated as between advertising and consumption, and should be further researched. Another implication is that it might not be appropriate to purely look at advertising and consumption to increase the further understanding of the two variables. Introducing household loans as a funding variable to the consumption function can be seen as a new and interesting approach.
50

A Study on Information Transmission and Volume-price Relationship in Taiwan Stock Index and Industrial Stock Index

Chang, Chen-wei 20 August 2007 (has links)
The purpose of this study is to research the volume-price relationship and information transmission among Taiwan Stock Index, Electronic Industry Index, Financial Industry Index and Plastic Industry Index. This study uses the time series methods of ADF unit root test, variance decomposition, Granger causality and impulse response analysis to proceed empirical research. It covers the period June 2, 2003, through December 29, 2006 and uses the daily data for sample. The empirical results can be summarized as follows¡G (1) All the trading volume and stock return series are trend stationary at level, therefore, they are integrated of order 0 ~ I (0). (2) The variance decomposition shows that the major change of every variable comes from by itself. The explanatory power of trading volume is higher than stock returns. Among the stock returns of Taiwan Stock Index, Electronic Industry Index, Financial Industry Index and Plastic Industry Index, Taiwan Stock Index has the highest explanatory power. (3) According to the Granger causality test, it expresses that trading volume leads stock returns. Taiwan Stock Index is the leading indicator of the Electronic Industry Index and Financial Industry Index. (4) As to the impulse response functions, neither persistent nor overall. The effect of shocks on all variables is transitory.

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