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811.
The model of latent structure analysis for k discrete-valued variates was explained and illustrated by R.D. G ill [5], Here the latent structure model is related to a condition for a covariance matrix, as in factor analysis theory, and a word of warning is given for the interpretation of a factor analysis from discrete valued variables.  相似文献   
812.
InM-estimation of the regression parameter vector in the linear model, we discuss the choice of the support of certain re-descendingψ-functions for both cases when the distribution of the i.i.d. errors is partially known and when it is completely functionally unknown. Research supported in part by the Natural Sciences and Engineering Research Council of Canada.  相似文献   
813.
814.
    
This study investigates the mediating role of work engagement (i.e. vigour and dedication) among job resources (i.e. job control, feedback and variety) and proactive behaviour at work. This mediating role was investigated, using Structural Equation Modelling in two independent samples from Spain (n = 386 technology employees) and the Netherlands (n = 338 telecom managers). Results in both samples confirmed that work engagement fully mediates the impact of job resources on proactive behaviour. Subsequent multigroup analyses revealed that the strengths of the structural paths of the mediation model were invariant across both national samples, underscoring the cross-national validity of the model  相似文献   
815.
816.
    
We revisit the meta-analysis of Sheremeta on overbidding in contest experiments and focus on the effect of endowment on overbidding. Sheremeta assumes, and finds evidence of, an increasing linear relationship between endowment and overbidding, Quantal Response Equilibrium (QRE) predicts an increasing concave relationship, while Baik and colleagues find an inverted U-shaped relationship in their analysis of a single experiment. We use the same data as in Sheremeta, but employ a different econometric model which leads to support for both QRE and the inverted U-shaped relationship. Following Baik and colleagues, we posit that the inverted-U relationship may be interpreted in terms of a wealth effect.  相似文献   
817.
    
This study conducted a large-scale survey in Dhaka, Bangladesh; the survey involved 95 major hospitals, more than 3000 emergency room patients, and 2 of the largest ambulance operators. Currently, most ambulances are parked within the vicinity of hospitals and are either dispatched or fetched by the acquaintances of the patient on demand, resulting in lengthy round trips. Reducing the response time of ambulances would certainly improve the emergency service, and pre-positioning of the ambulances could be a solution to reducing the response time. This study used two approaches to address the problem. First, the location-allocation problem was solved to find the optimal number of ambulance locations by maximising the demand coverage. Second, separate location-allocation for the peak and off-peaks, using K-means clustering, was applied to systematically optimise the ambulance positioning in small clusters near demand points. These approaches could substantially improve the existing emergency response time. Distributing ambulances near demand points yielded greater improvements in response time than when the ambulances are stationed near hospitals.  相似文献   
818.
Most empirical distributional studies of well-being in developed countries rely on distributions of disposable income. From a theoretical point of view this practice is contentious since a household’s command over resources is determined not only by its spending power over commodities it can buy in the market but also on resources available to the household members through non-market mechanisms such as the in-kind provisions of the welfare state and the value of private non-cash incomes. In developed market economies the most important private non-cash income component is imputed rent from owner-occupied or subsidized accommodation. Employing a wider definition of imputed rent that also allows the analyst to capture income advantages among tenants living in rent-subsidized accommodations of various sorts (including rent-free or reduced-rent households), the present paper examines the differential effects of including imputed rents in the concept of resources in five European countries (Belgium, Germany, Greece, Italy and the UK). The results suggest that in almost all cases, the inclusion of imputed rents in the concept of resources leads to a decline in measured levels of inequality and poverty. The main beneficiaries are outright homeowners and households living in rent-free (or heavily subsidized) accommodation—most often older persons. The inclusion of imputed rents in the concept of resources does not lead to substantial changes in the ranking of the countries according to their level of inequality, despite widespread differences in the rates of home ownership and subsidization across the countries studied here.  相似文献   
819.
Estimation of the scale matrix of a multivariate t-model under entropy loss   总被引:7,自引:0,他引:7  
This paper deals with the estimation of the scale matrix of a multivariatet-model with unknown location vector and scale matrix to improve upon the usual estimators based on the sample sum of product matrix. The well-known results of the estimation of the scale matrix of the multivariate normal model under the assumption of entropy loss function have been generalized to that of a multivariatet-model. The paper is based on the first author’s unpublished Ph.D. dissertation ‘Estimation of the Scale Matrix of a Multivariate T-model’, University of Western Ontario, Canada. Present address: School of Mathematics and Statistics, The University of Sydney, NSW 2006, Australia.  相似文献   
820.
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