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811.
Although providing informal care can negatively affect caregiver emotional health and lead to depression, the association between caregiver depression and missed work is unknown. We use data from the National Longitudinal Caregiver Survey to examine the relationship between caregiver depression and missed work among informal caregivers for older veterans with Alzheimer’s disease or vascular dementia. Two-part models are used to estimate the expected hours of work missed among working caregivers. Caregiver depression is statistically significantly associated with the likelihood and amount of time missed at work, resulting in an average of an extra half-day of work missed per month. While the effect of caregiver depression on work missed is modest, it represents another possible benefit from interventions to support caregivers.  相似文献   
812.
Failures of the reduction principle in an Ellsberg-type problem   总被引:1,自引:0,他引:1  
Segal (1987) suggested that the Ellsberg paradox might be explained in terms of individuals mentally representing the decision problem as a two-stage lottery which they evaluated according to a non-expected utility model. This paper describes an experiment involving an explicitly two-stage analogue to an Ellsberg-type problem. This design substantially reduces the frequency of classic Ellsberg behaviour, but reveals other systematic violations of conventional theory. The paper discusses the particular patterns of choice and raises the more general problem of modelling individual decisions when the reduction principle does not hold.  相似文献   
813.
Social Indicators Research - In order to control the spread of the COVID-19 pandemic, during the first wave of the pandemic numerous countries decided to adopt lockdown policies. It had been a...  相似文献   
814.
This paper introduces some new models of ecological inference within the context of estimation of voter transitions across elections. In particular, we assume that voters of a given party in a given occasion may be split into two latent types: faithful voters, who will certainly vote again for the same party and movers, who will reconsider their choice. Our models allow for unobserved heterogeneity across polling stations both in the weights of the two latent classes within each party and also when modelling the choice of unfaithful voters. Different ways of modelling the unobserved heterogeneity are considered by exploiting properties of the Dirichlet-multinomial distribution and the Brown Payne model of voting transitions can be seen as a special case within the class of models presented here. We discuss pseudo-maximum likelihood estimation and present an application to recent elections in Italy.  相似文献   
815.
Abstract

The libraries in the Western North Carolina Library Network (WNCLN) seek effective ways to provide patrons with a complete list of electronic journals provided through their various aggregator services, so patrons can determine e-journal access to article citations. The WNCLN libraries (Appalachian State University, the University of North Carolina at Asheville, and Western Carolina University) accomplished this through their shared catalog (Innovative Interfaces, Inc. [INNOPAC]), data provided by Serials Solutions, and local computer programming. Brief MARC records, with locally created key titles, provide an interim solution to the complexities of aggregator services. Serials Review 2002; 28:108–112.  相似文献   
816.
Measurement error and autocorrelation often exist in quality control applications. Both have an adverse effect on the chart's performance. To counteract the undesired effect of autocorrelation, we build-up the samples with non-neighbouring items, according to the time they were produced. To counteract the undesired effect of measurement error, we measure the quality characteristic of each item of the sample several times. The chart's performance is assessed when multiple measurements are applied and the samples are built by taking one item from the production line and skipping one, two or more before selecting the next.  相似文献   
817.
A new class of nonparametric tests, based on random projections, is proposed. They can be used for several null hypotheses of practical interest, including uniformity for spherical (directional) and compositional data, sphericity of the underlying distribution and homogeneity in two-sample problems on the sphere or the simplex. The proposed procedures have a number of advantages, mostly associated with their flexibility (for example, they also work to test “partial uniformity” in a subset of the sphere), computational simplicity and ease of application even in high-dimensional cases.  相似文献   
818.
Aiming to avoid the sensitivity in the parameters estimation due to atypical observations or skewness, we develop asymmetric nonlinear regression models with mixed-effects, which provide alternatives to the use of normal distribution and other symmetric distributions. Nonlinear models with mixed-effects are explored in several areas of knowledge, especially when data are correlated, such as longitudinal data, repeated measures and multilevel data, in particular, for their flexibility in dealing with measures of areas such as economics and pharmacokinetics. The random components of the present model are assumed to follow distributions that belong to scale mixtures of skew-normal (SMSN) distribution family, that encompasses distributions with light and heavy tails, such as skew-normal, skew-Student-t, skew-contaminated normal and skew-slash, as well as symmetrical versions of these distributions. For the parameters estimation we obtain a numerical solution via the EM algorithm and its extensions, and the Newton-Raphson algorithm. An application with pharmacokinetic data shows the superiority of the proposed models, for which the skew-contaminated normal distribution has shown to be the most adequate distribution. A brief simulation study points to good properties of the parameter vector estimators obtained by the maximum likelihood method.  相似文献   
819.
The autodependogram is a graphical device recently proposed in the literature to analyze autodependencies. This paper proposes a normalization of this diagram taking into consideration the concept of reproducibility probability (RP). The result is a novel tool, named RP-autodependogram, which permits to study the strength and the stability of the evidence about the presence of lag-dependence. A simulation study on well-established time-series models is carried out to investigate the behavior of the RP-autodependogram also in comparison with other diagrams studying autodependencies. An application to financial data is finally considered to appreciate its usefulness in the identification of parametric/nonparametric models.  相似文献   
820.
Since the end of the 1970s Italy has moved from being an out-migration country to being a foreign immigration country, but very few studies have addressed the factors determining the wages of immigrant workers, owing to the lack of available data. In this paper we analyse the determinants of the wages of immigrants in some areas of Latium and Campania, where the share of illegal immigration is relatively high, using the results of a set of sample surveys which collected information on several aspects of the immigration process in the years 1993–94. The purpose of the article is to shed some light on the factors underlying wage distribution among the immigrants using an estimation method that controls for sample selection problems. According to the empirical results, income differences seem to be relatively high among immigrants. Differences in labour market integration among sexes and area of origin clearly emerge from the results. Moreover, legal status plays an important role in the explanation of the wage gap between documented and undocumented immigrants, also because of the different occupational sector structure in the two groups.  相似文献   
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