• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 2
  • Tagged with
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 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

O Programa Bolsa Fam?lia estimula a migra??o dos trabalhadores de baixa renda ao mercado informal?

Godward, Carlos David 11 August 2017 (has links)
Submitted by Caroline Xavier (caroline.xavier@pucrs.br) on 2017-10-24T11:35:35Z No. of bitstreams: 1 DIS_CARLOS_DAVID_GODWARD_COMPLETO.pdf: 1317478 bytes, checksum: b5114678f308871a52be8844a408fe66 (MD5) / Approved for entry into archive by Caroline Xavier (caroline.xavier@pucrs.br) on 2017-10-24T11:35:49Z (GMT) No. of bitstreams: 1 DIS_CARLOS_DAVID_GODWARD_COMPLETO.pdf: 1317478 bytes, checksum: b5114678f308871a52be8844a408fe66 (MD5) / Made available in DSpace on 2017-10-24T11:36:01Z (GMT). No. of bitstreams: 1 DIS_CARLOS_DAVID_GODWARD_COMPLETO.pdf: 1317478 bytes, checksum: b5114678f308871a52be8844a408fe66 (MD5) Previous issue date: 2017-08-11 / Conditional Income Transfer Programs, Bolsa Fam?lia Program in Brazil, became an innovative instrument for reducing social inequality in many countries, specifically, in Latin America, where they were widely adopted. These programs have proven effective in several aspects such as reducing poverty and inequality, improving schooling rates, etc. An aspect that has remained unmentioned of these programs was their potential to encourage targeted workers of the program to migrate to the informal labour market in order to remain "invisible" to program managers and, thus, receive the benefits even when they do not qualify according to program standards. This study applies VECM (Vector Error Corrector Model) to show this issue may be occurring in the six Brazilian state capitals, included in the IBGE Monthly Employment Survey, from the creation of the program, in 2004, until March 2016. / Os Programas de Transfer?ncia de Renda Condicionada, Programa Bolsa Fam?lia no Brasil, foram uma forma inovadora de reduzir a desigualdade social em muitos pa?ses, principalmente da Am?rica Latina. Estes programas se mostraram eficientes em v?rios aspectos, como reduzir a pobreza, a desigualdade, melhorar ?ndices de escolaridade, etc. Mas, um aspecto pouco mencionado destes programas, ? o potencial de incentivar os trabalhadores - alvo do programa - a migrar para o mercado laboral informal, com o objetivo de ficarem ?invis?veis? aos gestores do programa e, assim, receberem os benef?cios, ainda que n?o se qualifiquem a eles, pelos n?veis de renda definidos pelo programa. Este trabalho utiliza o VECM (modelo Vector Corretor de Erros) para mostrar que este fato pode estar ocorrendo nas seis capitais do Brasil, que conformaram a Pesquisa Mensal de Emprego do IBGE, desde a cria??o do programa at? mar?o de 2016.
2

Previs?o do ?ndice bovespa por meio de redes neurais artificiais: uma an?lise comparada aos m?todos tradicionais de s?ries de tempo

Souza, Renata Laise Reis de 20 December 2011 (has links)
Made available in DSpace on 2014-12-17T13:53:32Z (GMT). No. of bitstreams: 1 RenataLRS_DISSERT.pdf: 1647146 bytes, checksum: 4d5eb3f745488991eeacb24559330562 (MD5) Previous issue date: 2011-12-20 / Forecast is the basis for making strategic, tactical and operational business decisions. In financial economics, several techniques have been used to predict the behavior of assets over the past decades.Thus, there are several methods to assist in the task of time series forecasting, however, conventional modeling techniques such as statistical models and those based on theoretical mathematical models have produced unsatisfactory predictions, increasing the number of studies in more advanced methods of prediction. Among these, the Artificial Neural Networks (ANN) are a relatively new and promising method for predicting business that shows a technique that has caused much interest in the financial environment and has been used successfully in a wide variety of financial modeling systems applications, in many cases proving its superiority over the statistical models ARIMA-GARCH. In this context, this study aimed to examine whether the ANNs are a more appropriate method for predicting the behavior of Indices in Capital Markets than the traditional methods of time series analysis. For this purpose we developed an quantitative study, from financial economic indices, and developed two models of RNA-type feedfoward supervised learning, whose structures consisted of 20 data in the input layer, 90 neurons in one hidden layer and one given as the output layer (Ibovespa). These models used backpropagation, an input activation function based on the tangent sigmoid and a linear output function. Since the aim of analyzing the adherence of the Method of Artificial Neural Networks to carry out predictions of the Ibovespa, we chose to perform this analysis by comparing results between this and Time Series Predictive Model GARCH, developing a GARCH model (1.1).Once applied both methods (ANN and GARCH) we conducted the results' analysis by comparing the results of the forecast with the historical data and by studying the forecast errors by the MSE, RMSE, MAE, Standard Deviation, the Theil's U and forecasting encompassing tests. It was found that the models developed by means of ANNs had lower MSE, RMSE and MAE than the GARCH (1,1) model and Theil U test indicated that the three models have smaller errors than those of a na?ve forecast. Although the ANN based on returns have lower precision indicator values than those of ANN based on prices, the forecast encompassing test rejected the hypothesis that this model is better than that, indicating that the ANN models have a similar level of accuracy . It was concluded that for the data series studied the ANN models show a more appropriate Ibovespa forecasting than the traditional models of time series, represented by the GARCH model / Nas organiza??es, a previs?o constitui a base para a tomada de decis?es estrat?gicas, t?ticas e operacionais. Na economia financeira, diversas t?cnicas t?m sido usadas a fim de prever o comportamento de ativos no decorrer das ?ltimas d?cadas. Assim, existem diversos m?todos para auxiliar na tarefa de previs?o de s?ries temporais, entretanto, t?cnicas de modelagem convencionais como modelos estat?sticos e aqueles baseados em modelos matem?ticos te?ricos t?m produzido previs?es insatisfat?rias, aumentando o n?mero de estudos em m?todos mais avan?ados de previs?o. Dentre estes, as Redes Neurais Artificiais (RNA) s?o um m?todo relativamente recente e promissor para a previs?o em neg?cios que se revela uma das t?cnicas que tem causado muito interesse no ambiente financeiro e tem sido utilizado com sucesso em uma ampla variedade de aplica??es de sistemas de modelagem financeiro, provado em muitos casos sua superioridade sobre os modelos estat?sticos ARIMA-GARCH (OLIVEIRA,2007). Nesse contexto, o presente trabalho teve por objetivo analisar se as RNAs s?o um m?todo mais adequado para a previs?o do comportamento de ?ndices em Mercados de Capital do que m?todos tradicionais de an?lise de s?ries temporais. Para tanto, foi desenvolvido um estudo quantitativo que, a partir de ?ndices econ?mico financeiros, elaborou dois modelos de RNA do tipo feedfoward de aprendizado supervisionado, cujas estruturas consistiram em 20 dados na camada de entrada, 90 neur?nios em uma camada oculta e um dado como camada de sa?da (?ndice Ibovespa). Estes modelos utilizaram BackPropagation, fun??o de ativa??o de entrada baseada na tangente Sigmoid e uma fun??o de sa?da linear. Visto o intuito de analisar a ader?ncia do M?todo de Redes Neurais Artificiais ? realiza??o de previs?es do Ibovespa, optou-se por realizar tal an?lise por meio da compara??o de resultados entre este e o M?todo de previs?o em s?ries temporais GARCH, desenvolvendo-se um modelo GARCH (1,1). Uma vez aplicadas ambas as metodologias (RNA e GARCH) e desenvolvidos os modelos, realizou-se a an?lise dos resultados obtidos comparando-se os resultados das previs?es com os dados hist?ricos e estudando-se os erros de previs?o por meio do MSE, RMSE, MAE, Desvio Padr?o, U de Theil e teste abrangente da previs?es. Verificou-se que os modelos desenvolvidos por meio de RNAs apresentaram menores MSE, RMSE e MAE que o modelo de controle e o teste U de Theil indicou que os tr?s modelos estudados apresentam erros menores que os de uma previs?o ing?nua. Embora a RNA baseada em retornos tenha apresentado valores dos indicadores de precis?o inferiores aos da RNA baseada em pre?os, o teste abrangente de regress?es rejeitou a hip?tese de que este modelo seja superior que aquele, indicando que os modelos de RNA apresentam um n?vel semelhante de precis?o. Concluiu-se que, para a s?rie de dados estudada neste trabalho, as Redes Neurais artificiais se mostram um modelo mais adequado de previs?o do que os modelos tradicionais de s?ries temporais, representado neste pelo m?todo GARCH

Page generated in 0.0917 seconds