Let there be m parallel machines and n jobs to be scheduled non-preemptively. A job j scheduled on machine i takes p_{i,j} time units to complete, where 1 ≤ i ≤ m and 1 ≤ j ≤ n. For a given schedule, the makespan is the completion time of a machine that finishes last. The goal is to produce a schedule of all n jobs with minimum makespan. This is known as the makespan problem on unrelated parallel machines (UPMs), denoted as R||C_{max}. In this thesis, we focus on subclasses of R||C_{max}. Our research consists of two components. First, a survey of theoretic results for R||C_{max} with a focus on approximation algorithms is presented. Second, we present exact polynomial-time algorithms and approximation algorithms for some subclasses of R||C_{max}. For instance, we present k-approximation algorithms on par with or better than the best known for certain subclasses of R||C_{max}.

This thesis presents three essays on Malaysia’s poverty profile based on the Household Expenditure Survey (HES). The first and second studies were motivated by the shortcomings of the official poverty lines and poverty measurements. There are several conceptual and measurement problems related to evaluating the extent of poverty in Malaysia. The first study offers several alternative regional poverty analyses based on the consumption expenditure approach with varying underlying assumptions. The poverty lines are estimated using Ravallion-Bidani and Kakwani-Sajaia approaches and the consumption pattern of the 10th and 20th percentile per capita expenditure (PCE) households. Regional poverty lines based on Kakwani-Sajaia and Ravallion-Bidani lower bounds produced robust poverty measurement rankings across regions in the country for both the 10th and 20th percentile PCE households. However, for the 10th percentile PCE, Ravallion’s upper bound poverty lines do not produce robust poverty rankings. In relation to the shortcomings of the official poverty measurements, the second study analyses the economies of scale in consumption, specifically amongst poor households. Using the 10th and 20th percentile PCE households, the household size economies are estimated using specifications proposed by Deaton-Paxson and Kakwani-Son. The findings show that the economies of scale indices are sensitive to the selection of methods and sample groups. Economies of scale in poor household consumption are present for food, housing, clothing, furnishing, personal goods and miscellaneous goods. This study further suggests that these indices be used as complementary to the existing national poverty measurements. The final study provides new insights into the limited urban poverty studies and to the new dimension of urban poverty. Using logistic regression, the determinants are analysed using the new poverty lines estimated in the earlier essay. The test of robustness of the determinants is conducted through re-estimating the logistic regression using a range of poverty lines. The findings show that education, locational dimension, foreign migrant workers and household size are significant determinants of poverty in the urban areas.

Submitted by RAUL DE SA DURLO null (durlo.raul@gmail.com) on 2016-11-29T01:51:08Z No. of bitstreams: 1 Durlo (2016) FINAL.pdf: 1806501 bytes, checksum: 74cd40ddb134f06e7c07175bed61a550 (MD5) / Approved for entry into archive by Felipe Augusto Arakaki (arakaki@reitoria.unesp.br) on 2016-12-02T11:59:30Z (GMT) No. of bitstreams: 1 durlo_rs_me_arafcl.pdf: 1806501 bytes, checksum: 74cd40ddb134f06e7c07175bed61a550 (MD5) / Made available in DSpace on 2016-12-02T11:59:30Z (GMT). No. of bitstreams: 1 durlo_rs_me_arafcl.pdf: 1806501 bytes, checksum: 74cd40ddb134f06e7c07175bed61a550 (MD5) Previous issue date: 2016-10-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Este trabalho tem como objetivo inferir sobre características e padrões espaços-temporais da criminalidade no contexto de uma grande cidade. O crime na sociedade é um problema complexo, que abrange um grande leque de interpretações e que passou a incorporar a agenda de pesquisa em economia principalmente após o trabalho seminal de Gary S. Becker (1968). De modo mais recente, é observado um crescente interesse nos aspectos geográficos da análise da criminalidade. Particularmente interessante é o fenômeno da criminalidade urbana, que em grandes centros apresentam padrões e dissimilaridades intra-regionais não negligenciáveis. A cidade de São Paulo é uma das grandes metrópoles mundiais, com quase 12 milhões de habitantes e com índices de criminalidade que impõem altos custos à qualidade de vida e ao bem-estar de seus habitantes. Neste trabalho, o fenômeno da criminalidade foi investigado do ponto de vista histórico e teórico, apontando os principais parâmetros para se interpretar o crime nas cidades. Posteriormente, discutiu-se a criminalidade no contexto do município de São Paulo com ênfase na década de 2000. Na abordagem empírica, as ocorrências de crimes contra pessoa e contra o patrimônio, registradas nos anos de 2003 e de 2013 nos distritos do município, foram relacionadas a varáveis socioeconômicas e de características do ambiente urbano por meio da metodologia SUR-espacial. Para comparabilidade entre Distritos Municipais e Distritos Policiais, foi formulada uma metodologia de agregação que os compatibilizassem em termos espaciais. Para detecção de não-aleatoriedade espacial nas ocorrências criminais foi calculada a estatística I de Moran. Os resultados corroboram com a hipótese de que o espaço urbano é importante para explicar a criminalidade em diversos aspectos, como por exemplo, as formas de uso do solo urbano, as condições de moradias e a proporção de empregos formais por moradores nos bairros. / The aim of this study is to infer about the crime and its spatial-temporal patterns and characteristics in the context of a big city. The crime in society is a complex issue, which covers a wide range of interpretations and began to incorporate the research agenda in economics especially after the seminal work of Gary S. Becker (1968). Recently, there has been a growing interest on geographical aspects in the analysis of crime. Particularly interesting is the urban crime phenomenon, which in large centers its patterns and intra-regional dissimilarities are not negligible. The city of São Paulo, in Brazil, is one of the world's great metropolises, with almost 12 million inhabitants and crime rates that impose high costs on the quality of life and well being of its inhabitants. In this study, the crime phenomenon was investigated by its historical and theoretical approach pointing out the main developments that account for interpreting the crime in cities. Thereafter, the crime was discussed in the São Paulo city context, with emphasis on 2000s. On the empirical approach, the criminal occurences against the person and the property in the years 2003 and 2013 by city districts were related with socioeconomic variables and urban environment features using the spatial-SUR methodology. In order to compare Municipal Districts with Police Districts, an aggregation methodology was formulated to merge them in spatial terms. Moreover, Moran I statistical was calculated for detection of spatial non-randomness on the criminal activities. The results corroborate the hypothesis that the urban space is important to explain the crime in many aspects, such as the forms of urban land use, the conditions of housing and the proportion of formal employment by residents in neighborhoods.

Este estudo têm como objetivo identificar qual o comportamento de empresas brasileiras de capital aberto com relação à aplicação dos recursos financeiros de seus fluxos de caixa (recursos internos) em investimentos e não investimentos (em fins que não se configuram como um projeto real de investimento) no curto e longo prazo e mostrar como essa questão está relacionado com o grau de restrições financeiras enfrentado pelas empresas. Para alcançar esse objetivo foram estimadas quatro regressões pelo método OLS (Ordinary Least Square / Mínimos Quadrados Ordinários), cada uma delas com uma das variáveis resposta correspondentes aos principais usos de caixa, ou seja, retenção de caixa, investimentos, dividendos e redução do financiamento externo e com as variáveis explicativas dadas pelo fluxo de caixa nos períodos t, t-1 e t-2 e algumas variáveis de controle específicas da firma. Os resultados sugerem que empresas brasileiras restritas e irrestritas se comportam de forma diferente ao receberem um choque positivo em seus fluxos de caixa e que o comportamento das mesmas também difere no curto e no longo prazo. Empresas restritas e irrestritas ao receberem um choque positivo em seus fluxos de caixa, retêm caixa no período contemporâneo e alocam tais recursos intertemporalmente. Empresas restritas investem mais no curto prazo enquanto as irrestritas investem mais no longo prazo. No curto prazo, empresas irrestritas distribuem mais dividendos do que empresas irrestritas e no longo prazo, os coeficientes dos fluxos de caixa não são significativos para nenhum dos grupos. No curto prazo empresas irrestritas reduzem o financiamento externo, enquanto empresas restritas levantam mais financiamentos externos e no longo prazo, esse comportamento se inverte. Dessa forma, fica clara a importância de se considerar o longo prazo bem como as restrições financeiras enfrentadas pelas empresas. / This study aim to identify what is the behaviour of Brazilian public companies regarding the use of financial resources of cash flows (internal resources) in investments and not investments (for purposes that are not configured as a real investment project) in the short and long term and show how this is related to the degree of financial constraints faced by firms. To achieve this aim, four regressions were estimated by OLS ( Ordinary Least Square), each with one of the response variables corresponding to the main uses of cash, ie , cash holding, investments, dividends and external finance reduction and the explanatory variables given by the cash flow in periods t , t - 1 and t - 2 and some control variables specific of the firm. The results suggest that restricted and unrestricted Brazilian companies behave differently when they receive a positive shock on cash flows and their behavior also differs in the short and long term. When constrained and unconstrained firms receive a positive impact on cash flows, they retain cash in the contemporary period and intertemporally allocate such resources. Constrained firms invest more in the short term while the unrestricted invest more in the long run. In the short term, unconstrained firms distribute more dividends than unconstrained firms and in the long run, the coefficients of cash flows are not significant for either groups. In the short term unconstrained firms reduce external finance, while constrained firms raise more external finance and in the long term, this behavior is reversed. Thus, it is clear that it matters to consider the long term as well as financial constraints faced by firms.

Submitted by Jaqueline Silva (jtas29@gmail.com) on 2014-12-08T17:37:44Z No. of bitstreams: 1 Tese-Thiago Santos-2013.pdf: 3081181 bytes, checksum: 2458be035ed935ff9e529ed2df6f9200 (MD5) / Rejected by Jaqueline Silva (jtas29@gmail.com), reason: on 2014-12-08T19:42:18Z (GMT) / Submitted by Jaqueline Silva (jtas29@gmail.com) on 2014-12-12T19:32:30Z No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Tese-Thiago Santos-2013.pdf: 3081181 bytes, checksum: 2458be035ed935ff9e529ed2df6f9200 (MD5) / Approved for entry into archive by Jaqueline Silva (jtas29@gmail.com) on 2014-12-16T09:22:12Z (GMT) No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Tese-Thiago Santos-2013.pdf: 3081181 bytes, checksum: 2458be035ed935ff9e529ed2df6f9200 (MD5) / Made available in DSpace on 2014-12-16T09:22:13Z (GMT). No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Tese-Thiago Santos-2013.pdf: 3081181 bytes, checksum: 2458be035ed935ff9e529ed2df6f9200 (MD5) Previous issue date: 2013-06-14 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / (Sem resumo em outra língua) / Dentre os mecanismos que geram as distribuições das espécies, tem sido atribuído um papel localàs interações biológicasenquanto que as causas de padrões regionais ou globais são atribuídas às variáveis abióticas.Recentemente,um número crescente de trabalhostem concluído que as interações biológicas interespecíficas apresentam efeitos significativos sobre os limites das distribuições das espécies e que a variação espacial em grande escala de atributos populacionais, como a densidade, é mais bem explicada pelas interações que pelas condições abióticas. Os objetivos deste trabalho são, portanto, mensurar a importância das interações biológicas na distribuição espacial das espécies, tanto em relação aos limites das distribuições quanto à variação espacial nas densidades populacionais e discutir novas técnicas para se incluir as interações interespecíficas nos modelos de distribuição potencial. No primeiro capítulo, um modelo estatístico de sistema de equações foi empregado para se verificar o efeito da competição entre duas espécies de cupins de montículos, Cornitermescumulans e Cornitermes silvestrii.No segundo capítulo, foi analisado o efeito da distribuição potencial de Crotalaria maypurensis (Fabaceae), sobre a distribuição potencial de Utetheisa ornatrix(Arctiidae). No terceiro capítulo, a distribuição de um predador de topo, Panthera onca, e a variação espacial de sua densidade populacional foram estimadas usando-se modelos alométricos de interação predador-presa.

Mind-wandering was until recently not a mainstream topic of research. The aim of this literature review is to present current views on the definition of mind-wandering and how the phenomenon is experienced. Furthermore, it gives an account of the implications of mind-wandering on cognitive performance, as well as its neurological correlates. In addition, the methods used to study mind-wandering are reviewed.The study of mind-wandering reveals a highly frequent phenomenon with practical consequences on a broad scale, both disruptive and supportive to goal-related behaviour and wellbeing in general. Originating from the default network, and its regions related to representations of self, memory, Theory of Mind, empathy and creativity, mind-wandering is hypothesized to be a function for planning one’s future life. Suggested further research concerns how mind-wandering can be countered, detected from the outside and whether it alters the physical feature of the brain.

Este estudo têm como objetivo identificar qual o comportamento de empresas brasileiras de capital aberto com relação à aplicação dos recursos financeiros de seus fluxos de caixa (recursos internos) em investimentos e não investimentos (em fins que não se configuram como um projeto real de investimento) no curto e longo prazo e mostrar como essa questão está relacionado com o grau de restrições financeiras enfrentado pelas empresas. Para alcançar esse objetivo foram estimadas quatro regressões pelo método OLS (Ordinary Least Square / Mínimos Quadrados Ordinários), cada uma delas com uma das variáveis resposta correspondentes aos principais usos de caixa, ou seja, retenção de caixa, investimentos, dividendos e redução do financiamento externo e com as variáveis explicativas dadas pelo fluxo de caixa nos períodos t, t-1 e t-2 e algumas variáveis de controle específicas da firma. Os resultados sugerem que empresas brasileiras restritas e irrestritas se comportam de forma diferente ao receberem um choque positivo em seus fluxos de caixa e que o comportamento das mesmas também difere no curto e no longo prazo. Empresas restritas e irrestritas ao receberem um choque positivo em seus fluxos de caixa, retêm caixa no período contemporâneo e alocam tais recursos intertemporalmente. Empresas restritas investem mais no curto prazo enquanto as irrestritas investem mais no longo prazo. No curto prazo, empresas irrestritas distribuem mais dividendos do que empresas irrestritas e no longo prazo, os coeficientes dos fluxos de caixa não são significativos para nenhum dos grupos. No curto prazo empresas irrestritas reduzem o financiamento externo, enquanto empresas restritas levantam mais financiamentos externos e no longo prazo, esse comportamento se inverte. Dessa forma, fica clara a importância de se considerar o longo prazo bem como as restrições financeiras enfrentadas pelas empresas. / This study aim to identify what is the behaviour of Brazilian public companies regarding the use of financial resources of cash flows (internal resources) in investments and not investments (for purposes that are not configured as a real investment project) in the short and long term and show how this is related to the degree of financial constraints faced by firms. To achieve this aim, four regressions were estimated by OLS ( Ordinary Least Square), each with one of the response variables corresponding to the main uses of cash, ie , cash holding, investments, dividends and external finance reduction and the explanatory variables given by the cash flow in periods t , t - 1 and t - 2 and some control variables specific of the firm. The results suggest that restricted and unrestricted Brazilian companies behave differently when they receive a positive shock on cash flows and their behavior also differs in the short and long term. When constrained and unconstrained firms receive a positive impact on cash flows, they retain cash in the contemporary period and intertemporally allocate such resources. Constrained firms invest more in the short term while the unrestricted invest more in the long run. In the short term, unconstrained firms distribute more dividends than unconstrained firms and in the long run, the coefficients of cash flows are not significant for either groups. In the short term unconstrained firms reduce external finance, while constrained firms raise more external finance and in the long term, this behavior is reversed. Thus, it is clear that it matters to consider the long term as well as financial constraints faced by firms.

Despite the potential benefits of larger datasets for crop insurance ratings, pooling yields with similar distributions is not a common practice. The current USDA-RMA county insurance ratings do not consider information across state lines, a politically driven assumption that ignores a wealth of climate and agronomic evidence suggesting that growing regions are not constrained by state boundaries. We test the appropriateness of this assumption, and provide empirical grounds for benefits of pooling datasets. We find evidence in favor of pooling across state lines, with poolable counties sometimes being as far as 2,500 miles apart. An out-of-sample performance exercise suggests our proposed pooling framework out-performs a no-pooling alternative, and supports the hypothesis that economic losses should be expected as a result of not adopting our pooling framework. Our findings have strong empirical and policy implications for accurate modeling of yield distributions and vis-à-vis the rating of crop insurance products.

Traffic crashes have been identified as one of the main causes of death in the US, making road safety a high priority issue that needs urgent attention. Recognizing the fact that more and effective research has to be done in this area, this thesis aims mainly at developing different statistical models related to the road safety. The thesis includes three main sections: 1) overall crash frequency analysis using negative binomial models, 2) seemingly unrelated negative binomial (SUNB) models for different categories of crashes divided based on type of crash, or condition in which they occur, 3) safety models to determine the probability of crash occurrence, including a rainfall index that has been estimated using a logistic regression model. The study corridor is a 36.25 mile stretch of Interstate 4 in Central Florida. For the first two sections, crash cases from 1999 through 2002 were considered. Conventionally most of the crash frequency analysis model all crashes, instead of dividing them based on type of crash, peaking conditions, availability of light, severity, or pavement condition, etc. Also researchers traditionally used AADT to represent traffic volumes in their models. These two cases are examples of macroscopic crash frequency modeling. To investigate the microscopic models, and to identify the significant factors related to crash occurrence, a preliminary study (first analysis) explored the use of microscopic traffic volumes related to crash occurrence by comparing AADT/VMT with five to twenty minute volumes immediately preceding the crash. It was found that the volumes just before the time of crash occurrence proved to be a better predictor of crash frequency than AADT. The results also showed that road curvature, median type, number of lanes, pavement surface type and presence of on/off-ramps are among the significant factors that contribute to crash occurrence. In the second analysis various possible crash categories were prepared to exactly identify the factors related to them, using various roadway, geometric, and microscopic traffic variables. Five different categories are prepared based on a common platform, e.g. type of crash. They are: 1) Multiple and Single vehicle crashes, 2) Peak and Off-peak crashes, 3) Dry and Wet pavement crashes, 4) Daytime and Dark hour crashes, and 5) Property Damage Only (PDO) and Injury crashes. Each of the above mentioned models in each category are estimated separately. To account for the correlation between the disturbance terms arising from omitted variables between any two models in a category, seemingly unrelated negative binomial (SUNB) regression was used, and then the models in each category were estimated simultaneously. SUNB estimation proved to be advantageous for two categories: Category 1, and Category 4. Road curvature and presence of On-ramps/Off-ramps were found to be the important factors, which can be related to every crash category. AADT was also found to be significant in all the models except for the single vehicle crash model. Median type and pavement surface type were among the other important factors causing crashes. It can be stated that the group of factors found in the model considering all crashes is a superset of the factors that were found in individual crash categories. The third analysis dealt with the development of a logistic regression model to obtain the weather condition at a given time and location on I-4 in Central Florida so that this information can be used in traffic safety analyses, because of the lack of weather monitoring stations in the study area. To prove the worthiness of the weather information obtained form the analysis, the same weather information was used in a safety model developed by Abdel-Aty et al., 2004. It was also proved that the inclusion of weather information actually improved the safety model with better prediction accuracy.

No description available.