This thesis consists of four self-contained essays. The first essay concerns educational choice and the returns to college in Sweden. I apply a recently introduced econometric framework that allows for self selection and treatment effect heterogeneity. I also examine the influence of cognitive and noncognitive ability on college choice and the returns to college. Essays two through four concern different aspects of intergenerational income mobility. In the second essay, we study the impact on mobility estimates from heterogeneous income profiles and, more specifically, life-cycle bias. We use nearly career-long income measures for both fathers and sons to give a detailed account of this bias and assess recent methods to deal with it. In the third essay, we present a simple model of intergenerational transmission and use it to analyze the dynamic behavior of the intergenerational income elasticity following structural changes. We find that past structural frameworks, for example in the form of past policies or institutions, matter for current trends in mobility. The fourth essay provides a cross-country perspective on intergenerational income mobility. We construct comparable data sets for Sweden and the UK and account for country differences in the role of parental income for various productivity traits of children. Finally, we examine whether such differences can explain the country difference in intergenerational income mobility.

cDNA microarrays is one of the first high-throughput gene expression technologies that has emerged within molecular biology for the purpose of functional genomics. cDNA microarrays compare the gene expression levels between cell samples, for thousands of genes simultaneously. The microarray technology offers new challenges when it comes to data analysis, since the thousands of genes are examined in parallel, but with very few replicates, yielding noisy estimation of gene effects and variances. Although careful image analyses and normalisation of the data is applied, traditional methods for inference like the Student t or Fisher’s F-statistic fail to work. In this thesis, four papers on the topics of empirical Bayes and full Bayesian methods for two-channel microarray data (as e.g. cDNA) are presented. These contribute to proving that empirical Bayes methods are useful to overcome the specific data problems. The sample distributions of all the genes involved in a microarray experiment are summarized into prior distributions and improves the inference of each single gene. The first part of the thesis includes biological and statistical background of cDNA microarrays, with an overview of the different steps of two-channel microarray analysis, including experimental design, image analysis, normalisation, cluster analysis, discrimination and hypothesis testing. The second part of the thesis consists of the four papers. Paper I presents the empirical Bayes statistic B, which corresponds to a t-statistic. Paper II is based on a version of B that is extended for linear model effects. Paper III assesses the performance of empirical Bayes models by comparisons with full Bayes methods. Paper IV provides extensions of B to what corresponds to F-statistics.

The Arctic represents a huge area with poor infrastructure contributing to limited possibilities to establish monitoring and research programs. From the investigations that have been performed we know that the arctic environment is affected by anthropogenic emissions from lower latitudes, but knowledge about underlying transport processes, the arctic pollution extent and the rates of changes are limited. This is of particular concern since we are facing climate changes that will not only influence the pole-ward transport of pollutants, but also change conditions for the already accumulated pollutants in the arctic environment. In this thesis lake sediments and soil samples are used to study sub-arctic and arctic time trends and loads of PCBs, PBDE, pesticides, mercury and lead. The study sites are the area around Kangerlussuaq, located in western Greenland, and the Swedish mountains. The temporal trends for PCBs (69 congeners), PBDE (#47) and two pesticides (chlordane and hexachlorobenzene) are studied in seven surface lake sediment cores from Greenland. The concentrations of these persistent organic pollutants are one to two orders of magnitude lower compared to lake sediments from lower latitudes, but with temporal trends following emission and usage trends at lower altitudes, i.e., decreasing trends for PCBs, increasing for PBDE and no specific trends for the pesticides. A delayed deposition of the low-chlorinated PCBs compared to the high-chlorinated PCBs may support the hypothesis of ‘cold condensation’ and ‘global fractionation’ i.e., volatile compounds are fractionated during the pole-ward transport. For lead the concentration in three Greenland lake sediments is about 10 times lower than in sediments from industrial regions, but the past 200 years’ temporal trends follow emission trends in industrial regions. The mercury concentration and enrichment following the Industrial Revolution in the mid 19th century are in three lake sediments from Greenland and in twelve lake sediments from the Swedish mountains comparable with those in sediments from industrial regions; a result of the long atmospheric residence-time for mercury, making it a global pollution. Recently decreased mercury emissions in North America and Europe give declining concentrations in the sediment surfaces, especially in lakes located in the Swedish mountains. In Greenland deeper sediment cores, spanning the last 8000 years, there are substantial fluctuations in mercury concentration and stable lead isotopes (206Pb/207Pb). These fluctuations are the result of variations in deposition to the lake of aeolian material, driven by past variations in arctic climate. In surface soil the mercury concentrations and inventories from the Swedish mountains are 1.5-2 times higher than in soils from Greenland, but for both regions the concentrations are below the critical concentration set up by UN-ECE to protect the terrestrial ecosystem. No indications for mercury enrichment in colder areas, as suggested by the hypothesis of ‘cold condensation’, or in coastal areas, as suggested by the hypothesis of ‘mercury depletion events’, were observed. The highly minerogenic surface soils in sub-arctic and arctic regions have reduced capacity to store mercury, compared to boreal soils.

Conselho Nacional de Desenvolvimento Científico e Tecnológico / Esta tese tem como foco os efeitos da desigualdade de renda na saúde bucal e as tendências em desigualdades socioeconômicas em saúde bucal. Qualquer injustiça social, pelo caráter moral é digna de estudo, porém nem toda desigualdade de renda é socialmente injusta. Ela se torna injusta quando as pessoas com menos recursos são aquelas que permitem que as desigualdades econômicas afetem direitos humanos, como o direito a um nível de vida que assegure ao indivíduo e a sua família uma vida saudável. As desigualdades de renda foram estudadas em duas vertentes:a) efeitos contextuais da desigualdade de renda na saúde bucal ; b) tendências na diferença de saúde bucal entre pessoas com maior e menor renda. A primeira parte contém quatro artigos originais que estudaram a associação e os mecanismos contextuais p elos quais a desigualdade de renda afeta a saúde bucal. Para isso, foram utilizados dados do inquérito em saúde bucal SBBrasil de 2002. Os resultados mostraram que: a) a associação entre desigualdade de renda e saúde bucal é mais forte em relação à cárie dental do que outras doenças bucais (e.g. doenças periodontais e maloclusões); b)seus efeitos estão mais fortemente associados à doenças bucais de menor latência; c) os efeitos associados à cárie dental afetam pobres e ricos igualmente; e d) a ausência de políticas públicas parece ser a melhor explicação para os efeitos da excessiva desigualdade de renda no Brasil. Ainda em relação às políticas públicas, foi encontrados que os ricos beneficiam-se mais de políticas públicas municipais do que os pobres. A segunda parte desta tese contém dois artigos originais que descrevem as tendências em saúde bucal e o uso dos serviços odontológicos em grupos de maior e menor renda, no Brasil e na Suécia. Para essas análises, foram usados dados dos inquéritos em saúde bucal no Brasil dos anos de 1986 e 2002, e para Suécia foram obtidos dados do "Swedish Level of Living Survey" para 1968, 1974, 1981, 1991 e 2000. As tendências relacionadas à prevalência de edentulismo mostraram que houve uma redução das desigualdade em percentuais absolutos nos dois países, porém, no Brasil houve um aumento das diferenças quando o desfecho foi a prevalência de nenhum dente perdido. As reduções das disparidades em edentulimo estiveram associadas à presença de uma diferença inicial significativa ,já o aumento das desigualdade na prevalência de nenhum dente perdido esteve relacionado a uma pequena desigualdade no início da coleta de dados. Em relação às desigualdades de uso dos serviços, ressalta-se que o grupo mais pobre permanece utilizando menos os serviços odontológicos em ambos os países e as diferenças continuam significantes através dos tempos. Entretanto, tanto no Brasil como na Suécia, essas diferenças reduziram levemente nas coortes jovens em função do declínio no percentual de pessoas mais ricas que visitam o dentista. Nossos dados permitem concluir que as desigualdades, em saúde bucal, mesmo em países altamente igualitários, como a Suécia. / This thesis focuses on the effect of income distribution on oral health and trends on socioeconomic disparities in oral health. Any social injustice, because of moral issues, is worth studying, though not all inequality of is unfair. Income inequality is unfair when people with less economic resources are penalized with poor health because of their condition of poverty. Unjust societies are those that allow economic inequalities to affect human rights as the right to a standard of living that ensures the individuals and their family a healthy life. Income inequalities were studied in two aspects: a) the contextual effects of income inequality in oral health, and; b) trends in the difference in oral health among people with higher and lower income. The first part contains 4 original articles that studied the association and the contextual mechanism by which income inequality affects oral health. For this we used data of the oral health survey SSBrasil in 2002. The results showed that: a) the association between income inequality and oral health is stronger in relation to dental caries than other oral diseases (e.g. periodontal diseases and malocclusions); b) the effects of inequality of income are more strongly associated with oral diseases of a shorter latency: c) that the effects associated with dental caries affect equally the rich and the poor. The second part of this thesis contains two original articles that described the trends in oral health and in the use of dental services into groups of higher and lower income, in Brazil and Sweden. For this analysis data were obtained from the Brazilian oral health surveys for the year 2002, while for Sweden were used data from the "Swedish Level of Living Survey" for the years 1968, 1974, 1981, 1991 and 2000. Trends in the prevalence of edentulismo showed a reduction in absolute disparities in both countries, but in Brazil trends in the prevalence of "no missing tooth" increased. Reductions in disparities in edentulismo were associated with the presence of a significant initiak difference, while the increase in inequality for outcome "no missing tooth" was related to small inequalities in the begining of data collection. Trends in the use of dental services highlighted that the poorer have been using less the dental services in both countries and the difference remain saignificant over time. however, in Brazil and Sweden, these differences decrease slightly in the cohort of young people because there was a decline in the percentage of rich people who visit the dentist. Our data show that income inequalities in oral health and use of dental serviceshave historically favored the more affluent population even in highly egalitarian countires as Sweden.

Conselho Nacional de Desenvolvimento Científico e Tecnológico / Esta tese tem como foco os efeitos da desigualdade de renda na saúde bucal e as tendências em desigualdades socioeconômicas em saúde bucal. Qualquer injustiça social, pelo caráter moral é digna de estudo, porém nem toda desigualdade de renda é socialmente injusta. Ela se torna injusta quando as pessoas com menos recursos são aquelas que permitem que as desigualdades econômicas afetem direitos humanos, como o direito a um nível de vida que assegure ao indivíduo e a sua família uma vida saudável. As desigualdades de renda foram estudadas em duas vertentes:a) efeitos contextuais da desigualdade de renda na saúde bucal ; b) tendências na diferença de saúde bucal entre pessoas com maior e menor renda. A primeira parte contém quatro artigos originais que estudaram a associação e os mecanismos contextuais p elos quais a desigualdade de renda afeta a saúde bucal. Para isso, foram utilizados dados do inquérito em saúde bucal SBBrasil de 2002. Os resultados mostraram que: a) a associação entre desigualdade de renda e saúde bucal é mais forte em relação à cárie dental do que outras doenças bucais (e.g. doenças periodontais e maloclusões); b)seus efeitos estão mais fortemente associados à doenças bucais de menor latência; c) os efeitos associados à cárie dental afetam pobres e ricos igualmente; e d) a ausência de políticas públicas parece ser a melhor explicação para os efeitos da excessiva desigualdade de renda no Brasil. Ainda em relação às políticas públicas, foi encontrados que os ricos beneficiam-se mais de políticas públicas municipais do que os pobres. A segunda parte desta tese contém dois artigos originais que descrevem as tendências em saúde bucal e o uso dos serviços odontológicos em grupos de maior e menor renda, no Brasil e na Suécia. Para essas análises, foram usados dados dos inquéritos em saúde bucal no Brasil dos anos de 1986 e 2002, e para Suécia foram obtidos dados do "Swedish Level of Living Survey" para 1968, 1974, 1981, 1991 e 2000. As tendências relacionadas à prevalência de edentulismo mostraram que houve uma redução das desigualdade em percentuais absolutos nos dois países, porém, no Brasil houve um aumento das diferenças quando o desfecho foi a prevalência de nenhum dente perdido. As reduções das disparidades em edentulimo estiveram associadas à presença de uma diferença inicial significativa ,já o aumento das desigualdade na prevalência de nenhum dente perdido esteve relacionado a uma pequena desigualdade no início da coleta de dados. Em relação às desigualdades de uso dos serviços, ressalta-se que o grupo mais pobre permanece utilizando menos os serviços odontológicos em ambos os países e as diferenças continuam significantes através dos tempos. Entretanto, tanto no Brasil como na Suécia, essas diferenças reduziram levemente nas coortes jovens em função do declínio no percentual de pessoas mais ricas que visitam o dentista. Nossos dados permitem concluir que as desigualdades, em saúde bucal, mesmo em países altamente igualitários, como a Suécia. / This thesis focuses on the effect of income distribution on oral health and trends on socioeconomic disparities in oral health. Any social injustice, because of moral issues, is worth studying, though not all inequality of is unfair. Income inequality is unfair when people with less economic resources are penalized with poor health because of their condition of poverty. Unjust societies are those that allow economic inequalities to affect human rights as the right to a standard of living that ensures the individuals and their family a healthy life. Income inequalities were studied in two aspects: a) the contextual effects of income inequality in oral health, and; b) trends in the difference in oral health among people with higher and lower income. The first part contains 4 original articles that studied the association and the contextual mechanism by which income inequality affects oral health. For this we used data of the oral health survey SSBrasil in 2002. The results showed that: a) the association between income inequality and oral health is stronger in relation to dental caries than other oral diseases (e.g. periodontal diseases and malocclusions); b) the effects of inequality of income are more strongly associated with oral diseases of a shorter latency: c) that the effects associated with dental caries affect equally the rich and the poor. The second part of this thesis contains two original articles that described the trends in oral health and in the use of dental services into groups of higher and lower income, in Brazil and Sweden. For this analysis data were obtained from the Brazilian oral health surveys for the year 2002, while for Sweden were used data from the "Swedish Level of Living Survey" for the years 1968, 1974, 1981, 1991 and 2000. Trends in the prevalence of edentulismo showed a reduction in absolute disparities in both countries, but in Brazil trends in the prevalence of "no missing tooth" increased. Reductions in disparities in edentulismo were associated with the presence of a significant initiak difference, while the increase in inequality for outcome "no missing tooth" was related to small inequalities in the begining of data collection. Trends in the use of dental services highlighted that the poorer have been using less the dental services in both countries and the difference remain saignificant over time. however, in Brazil and Sweden, these differences decrease slightly in the cohort of young people because there was a decline in the percentage of rich people who visit the dentist. Our data show that income inequalities in oral health and use of dental serviceshave historically favored the more affluent population even in highly egalitarian countires as Sweden.