Assuntos
Humanos , Feminino , Adolescente , Adulto Jovem , Pessoa de Meia-Idade , Censos , Taxa de Fecundidade , Fatores Etários , Brasil , Escolaridade , Fatores SocioeconômicosRESUMO
Estimates of fertility in small areas are valuable for analysing demographic change, and important for local planning and population projection. In countries lacking complete vital registration, however, small-area estimates are possible only from sparse survey or census data that are potentially unreliable. In these circumstances estimation requires new methods for old problems: procedures must be automated if thousands of estimates are required; they must deal with extreme sampling variability in many areas; and they should also incorporate corrections for possible data errors. We present a two-step procedure for estimating total fertility in such circumstances and illustrate it by applying the method to data from the 2000 Brazilian Census for over 5,000 municipalities. Our proposed procedure first smoothes local age-specific rates using Empirical Bayes methods and then applies a new variant of Brass's P/F parity correction procedure that is robust to conditions of rapid fertility decline. Supplementary material at the project website ( http://schmert.net/BayesBrass ) will allow readers to replicate all the authors' results in this paper using their data and programs.
Assuntos
Teorema de Bayes , Coeficiente de Natalidade , Censos , Fertilidade , Brasil , Coleta de Dados , Demografia , Países em Desenvolvimento , Humanos , Dinâmica PopulacionalRESUMO
Between 1960 and 2000, fertility fell sharply in Brazil, but this transition was unevenly distributed in space and time. Using Bayesian spatial statistical methods and microdata from five censuses, we develop and apply a procedure for fitting logistic curves to the fertility transitions in more than 500 small regions of Brazil over this 40-year period. Doing so enables us to map the main features of the Brazilian fertility transition in considerable detail. We detect early declines in some regions of the country and document large differences between early and late transitions in regard to both the initial level of fertility and the speed of the transition. We also use our results to test hypotheses regarding changes in the level of development at the onset of the fertility transition and identify a temporary stall in the Brazilian transition that occurred in the late 1990s. A web site with project details is at http://schmert.net/BayesLogistic.
Assuntos
Características Culturais , Fertilidade , Dinâmica Populacional , Saúde Pública , Mudança Social , Coeficiente de Natalidade/etnologia , Brasil/etnologia , Censos/história , Demografia , História do Século XX , História do Século XXI , Saúde Pública/economia , Saúde Pública/educação , Saúde Pública/história , Saúde Pública/legislação & jurisprudência , Mudança Social/história , Condições Sociais/economia , Condições Sociais/história , Condições Sociais/legislação & jurisprudênciaRESUMO
In this article, we analyze empirical Bayes (EB) methods for estimating small-area rate schedules. We develop EB methods that treat schedules as vectors and use adaptive neighborhoods to keep estimates appropriately local. This method estimates demographic rates for local subpopulations by borrowing strength not only from similar individuals elsewhere but also from other groups in the same area and from regularities in schedules across locations. EB is substantially better than standard methods when rates have strong spatial and age patterns. We illustrate this method with estimates of age-specific fertility schedules for over 3,800 Brazilian municipalities.
Assuntos
Teorema de Bayes , Demografia , Análise de Pequenas Áreas , Adolescente , Adulto , Brasil , Pesquisa Empírica , Feminino , Fertilidade , Humanos , Pessoa de Meia-IdadeRESUMO
Using microdata from the Brazilian demographic censuses of 1960, 1970, 1980, and 1991, aggregated into 518 consistently defined spatial units called microregions, we estimated fertility and mortality and constructed indicators of development and living conditions in the rural and urban areas of the microregions in each census. We then estimated cross-sectional and fixed-effects models to answer questions about the degree to which changes in these indicators are associated with changes in fertility and whether the relationship between fertility and development shifts through time. We found strong and consistent relationships between the decline in fertility and measurable changes in social and economic circumstances.
Assuntos
Coeficiente de Natalidade/tendências , Mudança Social , Adulto , Brasil , Censos , Estudos Transversais , Coleta de Dados , Demografia , Características da Família , Feminino , Humanos , Modelos Estatísticos , Análise Multivariada , População Rural , População UrbanaRESUMO
We propose a spatial generalized linear model (GLM) to analyse the vital rates for small areas. In each small area, we have a response vector and covariates to explain its variability. The statistical methodology is based on a spatial Bayesian approach and it allows the covariates' parameters of the generalized linear model to vary smoothly on space. Hence, the effect of a covariate on the response varies depending on the random variables measurement location. Our model is an extension of disease mapping models allowing the space-covariate interaction to be modelled in a natural way and giving space a position of intrinsic interest. We introduce the model in the context of fertility curve estimation. In each small area, we have a curve describing the variation of fertility rates by age modelled by Coale's fertility model, which implies a GLM in each area. A simulation shows the advantages of our approach. In addition, the paper applies the procedure to census data used to study the diffusion of low fertility behaviour in Brazil.