Uncovered set choice rules

I study necessary and sufficient conditions for a choice function to be rationalized in the following sense: there exists a total asymmetric relation T (a tournament) such that, for each feasible (finite) set, the choice set coincides with the uncovered set of T restricted to that feasible set. This notion of ‘maximization’ offers testable restrictions on observable choice behavior.     

Quantity quantiles linear regression

We show that the definition of the θth sample quantile as the solution to a minimization problem introduced by Koenker and Bassett (Econometrica 46(1):33–50, 1978) can be easily extended to obtain an analogous definition for the θth sample quantity quantile widely investigated and applied in the Italian literature. The key point is the use of the first-moment distribution of the variable instead of its distribution function. By means of this definition we introduce a linear regression model for quantity quantiles and analyze some properties of the residuals. In Sect. 4 we show a brief application of the methodology proposed. This research was partially supported by Fondo d’Ateneo per la Ricerca anno 2005—Università degli Studi di Milano-Bicocca. The paper is the result of the common work of the authors; in particular M. Zenga has written Sects. 1 and 5 while P. Radaelli has written the remaining sections.     

Análisis de la contextualización del comportamiento adaptativo en el retraso mental: Comparación entre contexto familiar e institucional

Resumen

Este estudio se dirige a contrastar las diferencias en el comportamiento adaptativo de los sujetos retrasados que son producto de los diferentes contextos en los que éste es emitido. En este caso, el contexto se entiende como los aspectos físicos y sociales del lugar en el que inmediatamente se produce la conducta. Esta perspectiva molecular del contexto ha permitido detectar diferencias en el comportamiento adaptativo en términos de lenguaje receptivo y lenguaje expresivo. La muestra utilizada fueron 71 sujetos evaluados a través del West Virginia assessment and tracking system.     

Leader–member exchange and empowerment: Direct and interactive effects on job satisfaction,turnover intentions,and performance

This study examined the moderating impact of empowerment on the relationships between leader–member exchange (LMX) quality and the self-rated outcomes of job satisfaction and turnover intentions, as well as the supervisor-rated outcomes of job performance and organizational citizenship behaviors. Two samples, with 244 and 158 employees respectively, were used to test our hypotheses. Our results provided evidence that in general, empowerment moderates the relationships between LMX and job outcomes. These findings are important as previous research has only tested these variables as independent predictors, but our results suggest the relationships these constructs have with important consequences are dependent on both variables. Practical implications and directions for future research are offered.     

Are clinician's ever biased in their judgments of the capacity of older adult's to make medical decisions?

Capacity assessment is a growing area of practice in geriatrics. In this pilot study we illustrate the potential relationship between clinician variables and capacity ratings. Twelve older adults with mild dementia or schizophrenia were rated by six clinicians from diverse disciplinary backgrounds. Capacity ratings were associated with clinician values regarding patient involvement in medical decisions, clinician-patient mismatches on such values, and emotional reactions to patients. Expanding our understanding of the impact of clinician variables on capacity ratings may enhance the reliability and validity of capacity assessments and help to promote autonomy when appropriate.     

Strategies Used by Gay and Bisexual Young Men to Cope with Heterosexism

Although the pervasiveness of heterosexism in the lives of gay and bisexual youth is well established, little is known about the strategies these youth use to cope with stigma and discrimination based on their sexual minority status. In this qualitative study, the authors present findings and implications for clinical practice based on interviews with 43 gay and bisexual young men. Respondents' coping strategies are discussed in relation to current theory and research on coping with stigma, as well as the emerging field of emotion regulation. The narratives from the current study suggest that the emotion regulation paradigm is well suited to understanding the functions of strategies for coping with heterosexism and similar types of stigma.     

Statistical analysis of process capability indices with measurement errors: The case ofC p

Process capability indices (PCIs) have been widely used in manufacturing industries to previde a quantitative measure of process potential and performance. While some efforts have been dedicated in the literature to the statistical properties of PCIs estimators, scarce attention has been given to the evaluation of these properties when sample data are affected by measurement errors. In this work we deal with the problem of measurement errors effects on the performance of PCIs. The analysis is illustrated with reference toC _p , i.e. the simplest and most common measure suggested to evaluate process capability. The authors would like to thank two anonymous referees for their comments and suggestion that were useful in the preparation and improvement of this paper. This work was partially supported by a MURST research grant.     

The role of self-advocacy in work for people with learning difficulties

This paper explores the relationship between self-advocacy and work for people with learning difficulties [1]. Explorations are based mainly on a participant observation study in which members of a self-advocacy group for people with learning difficulties included the researcher in their regular meetings. Discussions about work, most broadly defined as meaningful activity which makes a contribution to society, emerged as a critical preoccupation. We examine the importance of self-advocacy as a vehicle for people with learning difficulties who want to remove or circumvent barriers which surround their employment. Our research shows that understanding the role of self-advocacy in relation to work creates many development opportunities for both disabled employees and their prospective, or actual, employers. It is suggested that self-advocates can themselves achieve change in employers' attitudes by challenging oppressive images of people with learning difficulties in the workplace. It is hoped the paper will advance recognition of the importance of self-advocacy for maximising the participation of people with learning difficulties in work, and for acceptance of their status as workers.     

Some Comments Regarding the Synthetic Chart

The steady-state average run length (ARL) is a function of the in-control probabilities of being in each nonabsorbing state. Davis and Woodall (2002) tabulated values that are significantly smaller than the steady-state ARLs, because they used the out-of-control probabilities. The synthetic chart signals when a second sample point falls beyond the control limits, no matter whether one of them falls above the centerline and the other falls below it. The side-sensitive version of the synthetic chart does not signal when the points beyond the control limits are on opposite sides. With this rule, the chart detects mean changes more quickly.     

Estimation,prediction and interpretation of NGG random effects models: an application to Kevlar fibre failure times

We propose a class of Bayesian semiparametric mixed-effects models; its distinctive feature is the randomness of the grouping of observations, which can be inferred from the data. The model can be viewed under a more natural perspective, as a Bayesian semiparametric regression model on the log-scale; hence, in the original scale, the error is a mixture of Weibull densities mixed on both parameters by a normalized generalized gamma random measure, encompassing the Dirichlet process. As an estimate of the posterior distribution of the clustering of the random-effects parameters, we consider the partition minimizing the posterior expectation of a suitable class of loss functions. As a merely illustrative application of our model we consider a Kevlar fibre lifetime dataset (with censoring). We implement an MCMC scheme, obtaining posterior credibility intervals for the predictive distributions and for the quantiles of the failure times under different stress levels. Compared to a previous parametric Bayesian analysis, we obtain narrower credibility intervals and a better fit to the data. We found that there are three main clusters among the random-effects parameters, in accordance with previous frequentist analysis.