In studies of subjective well-being, economists and other researchers typically use a fixed or random effect estimation to control for unobservable heterogeneity across individuals. Such individual heterogeneity, although substantially reducing the estimated effect of many characteristics, is little understood. This paper shows that personality measures can account for 20% of this heterogeneity...

We discuss the use of fixed and random effects models in the context of educational research and set out the assumptions behind the two modelling approaches. To illustrate the issues that should be considered when choosing between these approaches, we analyse the determinants of pupil achievement in primary school, using data from the Avon Longitudinal Study of Parents and Children. We conclude...

An alternative to the classical mixedmodel with normal random effects is to use a Dirichlet process to model the random effects. Such models have proven useful in practice, and we have observed a noticeable variance reduction, in the estimation of the fixed effects, when the Dirichlet process is used instead of the normal. In this paper we formalize this notion, and give a theoretical justifica...

In this paper I discuss economic processes that may give rise to spatial patterns in data, and explore the relative merits of alternative modeling approaches when data are spatially correlated. Specifically, I present an estimation scheme that allows for spatial random effects, and focus attention on cases in which such a framework may be preferred to the more general fixed effects framework th...

climate change around the world is now a reality that has adverse effects on the environment and human health. there is little information about the effect of climate change on food systems, especially seafood from the farm to the table. the aim of this study was to review the fundamental effects of climate change on seafood safety and human health. climate change is expected to increase chemic...

background health expenditures are divided in two parts of public and private health expenditures. public health expenditures contain social security spending, taxing to private and public sectors, and foreign resources like loans and subventions. on the other hand, private health expenditures contain out of pocket expenditures and private insurances. each of these has different effects on the ...