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981.
Conventional parametric representations of stable law distributions do not allow all members of the family to be obtained as continuous limits of the parameters. Model building (or simulation) using such representations will be numerically unstable near such limits in consequence. Existing tables are not satisfactory near such limits as interpolation cannot be carried out. We show that these difficulties are overcome by using a new shifted Cartesian representation which characterizes the entire stable law family in a completely continuous way. Standardization is still possible with this representation so that tabulation, using just two bounded parameters, can be carried out. Its use is illustrated in a non-regular threshold estimation problem involving stable distributions which are discontinuous limits in conventional representations.  相似文献   
982.
The accelerated failure time (AFT) models have proved useful in many contexts, though heavy censoring (as for example in cancer survival) and high dimensionality (as for example in microarray data) cause difficulties for model fitting and model selection. We propose new approaches to variable selection for censored data, based on AFT models optimized using regularized weighted least squares. The regularized technique uses a mixture of \(\ell _1\) and \(\ell _2\) norm penalties under two proposed elastic net type approaches. One is the adaptive elastic net and the other is weighted elastic net. The approaches extend the original approaches proposed by Ghosh (Adaptive elastic net: an improvement of elastic net to achieve oracle properties, Technical Reports 2007) and Hong and Zhang (Math Model Nat Phenom 5(3):115–133 2010), respectively. We also extend the two proposed approaches by adding censoring observations as constraints into their model optimization frameworks. The approaches are evaluated on microarray and by simulation. We compare the performance of these approaches with six other variable selection techniques-three are generally used for censored data and the other three are correlation-based greedy methods used for high-dimensional data.  相似文献   
983.
We propose separate ratio estimators for population variance in stratified random sampling. We obtain mean square error equations and compare proposed estimators about efficiency with each other. By these comparisons, we find the conditions which make proposed estimators more efficient than others. It has been shown that proposed classes of estimators are more efficient than usual unbiased estimator. We find that separate ratio estimators are more efficient than combined ratio estimators for population variance. The theoretical results are supported by a numerical illustration with original data. A simulation study is also carried out to investigate empirical performance of estimators.  相似文献   
984.
A new statistic and a new method of analysis are proposed for data where a sample of respondents provides a preference ordering of some treatments. The new preference statistic is compared with the Friedman statistic, particularly for an example where 12 home owners each ranked four grasses. The new analysis provides a more natural and less misleading assessment of where the differences occur than an analysis based on the rank sums of the Friedman statistic. The new analysis is also more robust to deviations from the classical location problem, is not related to election methods known to have undesirable characteristics and adheres to the Condorcet criterion for election methods.  相似文献   
985.
This paper explores the identities projected in advertisements directed towards HIV positive individuals and people with AIDS. Fifty such advertisements were collected from three popular American magazines for gay men over a period of seven months. Analysis of the ads reveals a paradoxical presentation of people with HIV/AIDS, which offers simultaneous conflicting images of hope and fear, power and weakness, innocence and guilt. An interactive sociolinguistic model through which this contradictory discourse might be understood is presented, drawing on Goffman's insights on stigma management and the presentation of the self in social interaction. Advertisements directed towards people with HIV/AIDS, it is suggested, present a contradictory discourse in which the advertisers are positioned as 'the wise', offering to mediate the conflicting identities of the stigmatized. The identity values enacted in this contradictory discourse are further measured against American conceptions of communication and the self as observed by Carbaugh and others. The possible consequences of these positionings on the roles made available to people with HIV/AIDS in the wider social context are discussed.  相似文献   
986.
Uganda has made much progress towards including disabled people in its mainstream development, particularly in the political agenda. The exact process by which this has been achieved and the relationship between this and international guidelines and legislation are not known. This study undertakes to examine this from two specific perspectives: (1) How do international documents relevant to disabled people relate to national legislation in Uganda? (2) What can this comparison, together with the perceptions of stakeholders, tell us about how the legislation and services could improve? International legislation and Ugandan legislation is reviewed and compared. Data from 5 semi‐structured key informant interviews and 6 focus group discussions involving a total of 38 people are collected and analysed. The themes arising from the data are related to the documents, legislation, policies and other relevant literature. The results examine the barriers to service provision; the role of change; the importance of representation; policy and legislation issues; and the effects of devolution. Five specific findings relate to how legislation and services can improve: more resources to increase access for disabled people; strong leadership and collaboration between Disabled People’s Organisations (DPOs) funding bodies and governments; awareness raising and training; representation from all impairment groups; and raising the profile of disabled people through further legislation.  相似文献   
987.
Estonians are obliged by law to provide maintenance for family members who are unable to cope by themselves. As a result, 80% of fragile older people receive informal care. Whether this is because the carers themselves feel solidarity and choose informal caring or because they lack alternatives is the question. We applied the cultural approach for explaining the construction of compulsory family solidarity in care provision to older people through the perceptions of informal carers and policy actors. Our interest is in how filial norms framed by individual responsibilities of care provision required by law can influence (i) informal carers’ perceptions concerning their choices between work and care and (ii) impact policy actors’ perceptions concerning eldercare service provision. Analysing the empirical data produced during focus groups with female carers and interviews with policy actors, we demonstrate the triple‐fold pressure to informal caregiving as an expression of compulsory family solidarity. Key Practitioner Message: ? The article demonstrates how the national Family Law Act constitutes a compulsory requirement of family solidarity in society; ? The compulsory family solidarity norm influences local‐level policymaking and inhibits the development of formal care services for older people; ? Informal carers’ choices between work and care are shaped by their personal filial norms, familialistic policymaking, and pressure exerted by older people.  相似文献   
988.
A solution for two-person bargaining problems   总被引:1,自引:0,他引:1  
Everyday bargaining problems are often solved by tossing a coin. A solution for two-person bargaining problems is axiomatized, which is a Pareto-optimal generalization of this coin tossing method. The super-additive solution of Perles and Maschler is also shown to be a generalization of this method. Various properties of our solution are studied, including continuity and risk sensitivity, and compared with properties of other solutions discussed in the literature.This study was financed by the Yrjö Jahnsson Foundation, which is gratefully acknowledged. I like to thank an anonymous referee for useful comments.  相似文献   
989.
SIMULTANEOUS DETERMINATION OF CHURCH CONTRIBUTIONS AND CHURCH ATTENDANCE   总被引:1,自引:0,他引:1  
In a standard model of household allocation of time and income, church attendance and church contributions are determined simultaneously. There are life-cycle aspects to both attendance and contributions, as Azzi and Ehrenberg (1975) and Ehrenberg (1977) have argued, and contributions behavior is affected by tax treatment and by a potential free-rider problem as well. This paper motivates an econometric specification which recognizes these features and estimates the parameters with a data set of over 2000 Protestant church members.  相似文献   
990.
ABSTRACT The distribution of the cross-correlations of squared residuals from Box-Jenkins models is considered in very general conditions, and the asymptotic distribution is derived. A test for a lagged relationship in volatility for economic time series under instantaneous causality is proposed, and its empirical behaviour is studied. An example involving the international stock market's volatility is studied, and an interesting result is observed.  相似文献   
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