Search results for " Mixture models"

The many faces of human sociality: uncovering the distribution and stability of social preferences

2018

There is vast heterogeneity in the human willingness to weigh others' interests in decision making. This heterogeneity concerns the motivational intricacies as well as the strength of other-regarding behaviors, and raises the question how one can parsimoniously model and characterize heterogeneity across several dimensions of social preferences while still being able to predict behavior over time and across situations. We tackle this task with an experiment and a structural model of preferences that allows us to simultaneously estimate outcome-based and reciprocity-based social preferences. We find that non-selfish preferences are the rule rather than the exception. Neither at the level of …

Unbundling technology adoption and tfp at the firm level. Do intangibles matter?

2012

We use a panel of European firms to investigate the relationship between intangible assets and productivity. We distinguish between total factor productivity (tfp) and technology adoption, whereas standard estimations consider only a notion of productivity that conflates the two effects. Although we are unable to address simultaneity, we allow for the existence of multiple technologies within sectors through a mixture model approach. We find that intangible assets have nonnegligible effects that both push firms toward better technologies (technology adoption effects) and allow for more efficient exploitation of a given technology (tfp effects).

Labor productivity and firm-level TFP with technology-specific production functions

2020

Abstract We investigate the technological dimension of productivity, presenting an empirical methodology based on mixture models to disentangle the labor productivity differences associated with the firm's choice of technology (BTFP) and those related to the firm's ability to exploit the adopted technology (WTFP). The estimation endogenously determines the number of technologies (in the sector) and degree of technology sharing across firms (i.e., for each firm, the probability of using a given technology). By using comparable data for about 35,000 firms worldwide distributed across 22 (two-digit) sectors, we show BTFP to be at least as important as WTFP in explaining the labor productivity …

Evolution of the Global Distribution of Carbon Dioxide: A Finite Mixture Analysis

2015

Economists and environmental policymakers have recently begun advocating a bottom-up approach to climate change mitigation, focusing on reduction targets for groups of nations, rather than large scale global policies. We advance this discussion by taking a quantitative perspective, focusing on econometric identification of groups of countries that have statistically similar distributions of carbon emissions using a broad range of finite mixture models. Nearly all of our results yield a consistent pattern: after 1980, there are two distinct emissions distributions, and that these distributions continue to evolve over time. We provide a rigorous analysis of these distributional differences al…

Early life body mass trajectories and mortality in older age: Findings from the Helsinki Birth Cohort Study

2014

Overweight and obesity in childhood have been linked to an increased risk of adult mortality, but evidence is still scarce.We identified trajectories of body mass index (BMI) development in early life and investigated their mortality risk. Data come from the Helsinki Birth Cohort Study, in which 4943 individuals, born 1934-1944, had serial measures of weight and height from birth to 11 years extracted from health care records, weight and height data in adulthood, and register-based mortality data for 2000-2010.Three early BMI trajectories (increasing, average, and average-to-low for men and increasing, average, and low-to-high BMI for women) were identified. Women with an increasing or low-…

A robust aerial image registration method using Gaussian mixture models

2014

Aerial image registration is one of the bases in many aerospace applications, such as aerial reconnaissance and aerial mapping. In this paper, we propose a novel aerial image registration algorithm which is based on Gaussian mixture models. First of all, considering the characters of the aerial images, the work uses a shape feature detector which computes the boundaries of regions with nearly the same gray-value to extract invariant feature. Then, a Gaussian mixture models (GMM) based image registration model is built and solved to estimate the transformation matrix between two aerial images. Furthermore, the proposed method is applied on real aerial images, and the results demonstrate the …

The use of diagnostic tools in GAMLSS for liver fibrosis detection

Incentive and Selection Effects of Medigap Insurance on Inpatient Care

2012

The Medicare program, which provides insurance coverage to the elderly in the United States, does not protect them fully against high out-of-pocket costs. For this reason private supplementary insurance, named Medigap, has been available to cover Medicare gaps. This paper studies how Medigap affects the utilization of inpatient care, separating the incentive and selection effects of supplementary insurance. For this purpose, we use two alternative estimation methods: a standard recursive bivariate probit and a discrete multivariate finite mixture model. We find that estimated incentive effects are modest and quite similar across models. On the other hand, there seems to be very significant …

INEQUALITIES AND TOURISM CONSUMPTION BEHAVIOUR: A MIXTURE MODEL ANALYSIS

2015

The criticism of income as a measure of well-being and trends in living standards is well known and recently scholars have been involved in defining measures to better assess material well-being and differences in living standards. Recent evidence shows that individuals improve their well-being significantly if they are able to spend on higher-order goods and services like tourism and leisure activities. In the light of that, our study proposes to explore differences in living standards in Italy by analysing the distribution of tourism expenditure. For this aim, Mixtures of Regression Models were used in order to investigate whether there is an unobserved heterogeneity in tourism consumptio…

Ranking Scientific Journals Via Latent Class Models for Polytomous Item Response Data

2015

Summary We propose a model-based strategy for ranking scientific journals starting from a set of observed bibliometric indicators that represent imperfect measures of the unobserved ‘value’ of a journal. After discretizing the available indicators, we estimate an extended latent class model for polytomous item response data and use the estimated model to cluster journals. We illustrate our approach by using the data from the Italian research evaluation exercise that was carried out for the period 2004–2010, focusing on the set of journals that are considered relevant for the subarea statistics and financial mathematics. Using four bibliometric indicators (IF, IF5, AIS and the h-index), some…