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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.
1

Modelo de previsão aplicado ao mercado de transporte rodoviário do açúcar no estado de São Paulo / Prediction model applied to the road transport market of sugar in the State of São Paulo

Costa, Gilberto Fernandes da 29 April 2014 (has links)
A pesquisa tem como objetivo obter previsões para o mercado de fretes do açúcar para exportação no Estado de São Paulo. Para cumprir tal objetivo, utilizou-se a metodologia Box- Jenkins de séries temporais. O período compreendido na pesquisa foi janeiro de 2006 a setembro de 2013. Foram delimitadas no Estado de São Paulo nove regiões para análise: Ribeirão Preto, Jaú, Araraquara, Presidente Prudente, Araçatuba, Piracicaba, São José do Rio Preto, Pirassununga e Assis. Essas regiões também foram agregadas com o objetivo de obter previsões para o Estado de São Paulo. As previsões foram realizadas fora da amostra correspondendo ao período de outubro de 2012 a setembro de 2013. Os modelos estimados, de forma geral, obtiveram um bom desempenho considerando os cinco primeiros meses de previsão, como o ocorrido nas regiões de Jaú, Araraquara, Piracicaba, Pirassununga e Assis. Dentre as nove regiões analisadas, os modelos ajustados para as Regiões de Piracicaba e Assis apresentaram melhores desempenhos, fato este comprovado pelos menores valores do Erro Quadrático Médio e Soma do Quadrado dos Desvios. Considerando os resultados gerais das nove regiões e da análise do Estado de São Paulo de forma agregada, houve predomínio do emprego do modelo ARIMA como melhor método para a realização de previsões para o mercado de fretes do açúcar. Não obstante, as previsões geradas pela metodologia Box- Jenkins, no curto prazo, constituem em boa ferramenta de auxílio para tomada de decisões e planejamento dos agentes envolvidos no mercado do açúcar. / The research aims to obtain predictions for the freights market of sugar for export in the State of São Paulo in Brazil. A Box-Jenkins time series methodology was used to fulfill this objective. The survey was performed from January 2006 through September 2013. Nine regions in São Paulo State were placed for analysis: Ribeirão Preto, Jaú, Araçatuba, Araraquara, Piracicaba, São José do Rio Preto, Pirassununga, Presidente Prudente and Assis and also these regions were aggregated in order to obtain estimates for the State of São Paulo. The predictions were made out of the sample corresponding to the period from October 2012 to September 2013. The estimated models generally presented good performance considering the five first months of forecast, as occurred in the regions of Jaú, Araraquara, Piracicaba, Pirassununga and São José do Rio Preto. Out of the nine regions analyzed, the models adjusted for the regions of Piracicaba and Assis showed better performances, proven by the lowest average square error and Sum of Squares of deviations. Considering the overall results of the nine regions and the analysis of the state of São Paulo aggregated, employment ARIMA model predominated as the best method for performing predictions for the freight market sugar. Nevertheless, the forecasts generated by the Box-Jenkins methodology, in a short term, constitute good tool to aid decision-making and planning of the agents involved in the sugar market.
2

Modelo de previsão aplicado ao mercado de transporte rodoviário do açúcar no estado de São Paulo / Prediction model applied to the road transport market of sugar in the State of São Paulo

Gilberto Fernandes da Costa 29 April 2014 (has links)
A pesquisa tem como objetivo obter previsões para o mercado de fretes do açúcar para exportação no Estado de São Paulo. Para cumprir tal objetivo, utilizou-se a metodologia Box- Jenkins de séries temporais. O período compreendido na pesquisa foi janeiro de 2006 a setembro de 2013. Foram delimitadas no Estado de São Paulo nove regiões para análise: Ribeirão Preto, Jaú, Araraquara, Presidente Prudente, Araçatuba, Piracicaba, São José do Rio Preto, Pirassununga e Assis. Essas regiões também foram agregadas com o objetivo de obter previsões para o Estado de São Paulo. As previsões foram realizadas fora da amostra correspondendo ao período de outubro de 2012 a setembro de 2013. Os modelos estimados, de forma geral, obtiveram um bom desempenho considerando os cinco primeiros meses de previsão, como o ocorrido nas regiões de Jaú, Araraquara, Piracicaba, Pirassununga e Assis. Dentre as nove regiões analisadas, os modelos ajustados para as Regiões de Piracicaba e Assis apresentaram melhores desempenhos, fato este comprovado pelos menores valores do Erro Quadrático Médio e Soma do Quadrado dos Desvios. Considerando os resultados gerais das nove regiões e da análise do Estado de São Paulo de forma agregada, houve predomínio do emprego do modelo ARIMA como melhor método para a realização de previsões para o mercado de fretes do açúcar. Não obstante, as previsões geradas pela metodologia Box- Jenkins, no curto prazo, constituem em boa ferramenta de auxílio para tomada de decisões e planejamento dos agentes envolvidos no mercado do açúcar. / The research aims to obtain predictions for the freights market of sugar for export in the State of São Paulo in Brazil. A Box-Jenkins time series methodology was used to fulfill this objective. The survey was performed from January 2006 through September 2013. Nine regions in São Paulo State were placed for analysis: Ribeirão Preto, Jaú, Araçatuba, Araraquara, Piracicaba, São José do Rio Preto, Pirassununga, Presidente Prudente and Assis and also these regions were aggregated in order to obtain estimates for the State of São Paulo. The predictions were made out of the sample corresponding to the period from October 2012 to September 2013. The estimated models generally presented good performance considering the five first months of forecast, as occurred in the regions of Jaú, Araraquara, Piracicaba, Pirassununga and São José do Rio Preto. Out of the nine regions analyzed, the models adjusted for the regions of Piracicaba and Assis showed better performances, proven by the lowest average square error and Sum of Squares of deviations. Considering the overall results of the nine regions and the analysis of the state of São Paulo aggregated, employment ARIMA model predominated as the best method for performing predictions for the freight market sugar. Nevertheless, the forecasts generated by the Box-Jenkins methodology, in a short term, constitute good tool to aid decision-making and planning of the agents involved in the sugar market.
3

Analýza vývoje míry nezaměstnanosti v ČR / Analysis of trend of unemployment rate in Czech Republic

Jeřábková, Věra January 2008 (has links)
The unemployment is one of the main economic indicators. Thanks to time series analysis and predicting values, we can take measures of eliminating negative aspects of the unemployment in the economy. This thesis is concentrated on connection between theory of unemployment with time series analysis of unemployment rate, especially based on Box-Jenkins methodology.
4

Analýza vývoje výroby a spotřeby elektrické energie v ČR / Analysis of production and consumption of electricity in Czech republic

Melichar, Vojtěch January 2008 (has links)
This master thesis is divided into two parts. First part focuses on production and consumption of electricity in the Czech republic, describing sources of the production and their progress since 1990, considering also the main electricity consumers. The end of the first part focuses on the Box-Jenkins methodology, time series of electricity consumption between 1981 and 2008 are created as well as forecasted up to 2011. The second part of this thesis describes the cluster analysis. This is used for finding similarities of the 27 states of the European Union. Cluster analysis is applied for years 1990 and 2007, for both electric power production and electric power consumption.
5

Analýza sňatečnosti a rozvodovosti v ČR a vybraných zemích EU / Analysis of nuptiality and divorce rate in Czech Republic and selected countries of European Union

Plocová, Michaela January 2012 (has links)
This thesis is focused on two demographic processes -- nuptiality and divorce rate. The goal of this thesis is to analyze past, present and future development of nuptiality and divorce rate in Czech Republic and to draw a comparison between this development and the development in selected countries of European Union. The evaluation of the past and present development is made by using selected indicators of nuptiality and divorce rate. The forecast of the future development is obtained by using the Box-Jenkins methodology. The comparison of nuptiality and divorce rate in Czech Republic and in selected countries of European Union (Italy, Netherlands, Slovakia, Spain and Sweden) is to be found in the last chapter of this thesis.
6

Analýza a srovnání časových řad pomocí statistických metod / Time Series Analysis and Comparison by Means of Statistical Methods

Kopecký, Radek January 2009 (has links)
The aim of the thesis mainly is to understand an issue of time series analysis. There are many methods in time series analysis, but purpose of this analysis persists the same, which is a construction of sufficient model of time series and his application in forecasting of time series. We have to make a basic identification of time series to establish right process in model constructing. The first and the second chapter is devoted to this basic identification. There are many methods, how we said before, for constructing of concrete model. In this thesis, exactly in the third chapter, we introduce one of the most flexible methodology of model constructing. That is The Box-Jenkins methodology, which was defined in 1976 by these men. In the last chapter we try to put to use insight in the issue of time series analysis for comparison and separation of the space of time series and this comparison use for the right interpretation of the parameters of time series model. The diploma project was supported by project from MSMT of the Czech Republic no. 1M06047 "Centre for Quality and Reliability of Production".
7

Vliv chyb v modelu regrese / Influence of errors to regression model

Poliačková, Vlasta January 2013 (has links)
Title: Influence of errors to regression model Author: Bc. Vlasta Poliačková Department: Department of Probability and Mathematical Statistics Supervisor: doc. RNDr. Petr Lachout, CSc. Supervisor's e-mail address: Petr.Lachout@mff.cuni.cz Abstract: The submitted work deals with the regression model, and the influence of errors to regression. Thesis describes different types of violations of assumptions re- quired to the error term and their impact to the properties of the regression model. In the next part, there are discussed various statistical approaches applicable in the case of violation assumptions of regression model such as heteroscedasticity or autocor- relation of the residuals. In the application part, there is used mainly knowledge of Box - Jenkins methodology. In this section it is described in detail how to build a Box - Jenkins models and forecasts of future values for various real financial time series. In processing of the data are used models of ARMA, ARIMA and SARIMA. In an example, forecasts of the models are compared to real future values of the time series. Keywords: regression, violation of assumptions, error term, Box-Jenkins methodo- logy, time series
8

Odhady časových řad pomocí modelů neuronových sítí / Time series annalyze by neural networks models

Jiráň, Robin January 2017 (has links)
This thesis deals about using models of neural networks like alternative of time series model based on Box-Jenkins methodology. The work is divided into two parts according to the model construction method. Each of the parts contains a theory that explains the individual processes and the progress of the model construction. This is followed by two experiments demonstrating the difference in approach to the design of a given model and creating a forecast by estimated values. for the following year. The last part expertly evaluates the quality of the predictions and considers the use of neural networks against prediction models as an alternative to Box-Jenkins methodology based models
9

Výstavba lineárnych stochastických modelov časových radov triedy SARIMA – automatizovaný postup / Construction of Linear Stochastic Models of SARIMA Class Time Lines – Automatized Method

Trcka, Peter January 2015 (has links)
This work concerns the creation of automatized procedure of ARIMA and SARIMA class model choice according to Box-Jenkins methodology and in this connection, also deals with force testing of unit roots and analysis of applying of informatics criteria when choosing a model. The goal of this work is to create an application in the environment R that can automatically choose a model of time array generating process. The procedure is verified by a simulation study. In this work an effect of values of generating ARMA (1,1) model processes parameters is examined, for his choice and power of KPSS test, augmented Dickey-Fuller and Phillips-Peron test of unit roots.
10

Analýza vývoje průměrné mzdy v České republice / Analysis of average wage in Czech Republic

Zimmerhaklová, Tereza January 2010 (has links)
This thesis is focused on analysis of the development of gross month wage and in particular on development and examining seasonality. There are also described the institutions and their surveys of wages, such as the Czech Statistical Office, Ministry of Finance and the Ministry of Labor and Social Affairs, which administers the Information System of Average Earnings. The monthly income is compared between regions and between major classes KZAM. The development of time series is modeled by the Box-Jenkins methodology, further charts of seasonal values and seasonal indexes . For comparison the average relative wage growth in regions are used cartograms. The base for these analyses is data obtained from business statistical return systems and structural statistics from the site of the Czech Statistical Office and the Ministry of Labor and Social Affairs.

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