Single use conservative confidence regions in multivariate controlled calibration

We consider a multivariate linear model for multivariate controlled calibration, and construct some conservative confidence regions, which are nonempty and invariant under nonsingular transformations. The computation of our confidence region is easier compared to some of the existing procedures. We illustrate the results using two examples. The simulation results show the closeness of the coverage probability of our confidence regions to the assumed confidence level.     

Culture of Peace: Sociostructural Dimensions, Cultural Values, and Emotional Climate

This article examines how objective measures of sociostructural dimensions of a culture of peace are related to subjective national values, attitudes, and emotional climate. National scores on objective measures of four sociostructural dimensions were correlated with national means from a number of cultural value data sets and national indexes of emotional climate. Liberal Development was congruently associated with egalitarian, individualist values, a low negative emotional climate, and less willingness to fight in a new war. By contrast, Violent Inequality was associated with lower harmony values and less valuing of intellectual autonomy. State Use of Violent Means was strongly associated with low harmony values. Nurturance was associated with horizontal individualism, tolerance, cooperative values, and positive emotional climate. The conclusion discusses how the construction of a culture of peace must be based on values as well as objective sociocultural factors.     

Genetics of pathological gambling

Pathological gambling (PG) is an impulse control disorder and a model behavioral addiction. Familial factors have been observed in clinical studies of pathological gamblers, and twin studies have demonstrated a genetic influence contributing to the development of PG. Serotonergic, noradrenergic, and dopaminergic dysfunction have been reported as biological factors contributing to the pathophysiology of PG. Molecular genetic techniques have been used to investigate the role of genetic factors in PG. Molecular genetic research has identified specific allele variants of candidate genes corresponding to these neurotransmitter systems to be associated with PG. Associations have been reported between pathological gamblers and allele variants of polymorphisms at dopamine receptor genes, the serotonin transporter gene, and the monoamine-oxidase A gene. Although preliminary data suggest that some of these differences are gender-specific, more research needs to be performed to substantiate gender-specific genetic contributions to the development of pathological gambling. The review of the current findings on genetics of PG suggests that liability to PG is in part mediated by genetic factors. Additional studies are needed to replicate and extend these findings, as well as to better understand the influence of specific allelic variants to differences in biological and behavioral functioning.     

Validation of a Measure of Intimate Partner Abuse (Relationship Behavior Rating Scale–Revised) Using Item Response Theory Analysis

There is a need for a screening instrument to provide insight into intimate partner abuse (IPA) to inform legal decisions in child custody, divorce, child welfare, and criminal cases. This study is the third validation of the Relationship Behavior Rating Scale–Revised (RBRS–R) for concurrent validity with the widely used Conflict Tactics Scales 2 (CTS2). Item response theory results show that the RBRS–R compares favorably to the CTS, but also provides a higher degree of resolution than the CTS2 with respect to additional elements of IPA that can be manifested in different situations or individuals. This additional information might be very important in determining the safest legal process (mediation versus traditional litigation) and appropriate case outcomes to protect victims of violence.     

Influence of Age on Transracial Foster Adoptions and Its Relation to Ethnic Identity Development

In the United States, ethnic minorities are disproportionately represented in the foster care system and underrepresented among potential adoptive parents. The need to find permanent homes for foster children has led to an increase in the controversial practice of transracial adoption (TRA), wherein ethnic minority children are placed in adoptive homes with Caucasian parents. While many child welfare scholars and dependency stakeholders support TRA as a positive alternative to foster care, others are concerned that such adoptions may inhibit the ethnic identity development of transracially adopted children. This article documents the large number of ethnic minority children who are adopted through TRA prior to the onset of ethnic identification and how age influences which children are adopted out of foster care. The findings indicate that young ethnic minorities are significantly more likely to be adopted through TRA compared to older children, an effect especially prominent among African Americans. Implications for the child welfare system are discussed.     

Sexual Compulsivity and Sexual Behaviors Among Gay and Bisexual Men and Lesbian and Bisexual Women

Within the existing body of research, the information pertaining to sexual compulsivity (SC) among women, both homo- and heterosexual, remains rather limited in comparison to men. The aim of this study was to assess the prevalence of SC in a community sample of gay and bisexual men and lesbian and bisexual women and to identify differences in sexual practices based on classification as sexually compulsive within gender. Supporting previous research, the findings indicated that gay and bisexual men were significantly higher in SC when compared to lesbian and bisexual women. Similarly, sexually compulsive gay and bisexual men were more likely to report drug use with sex than their non-sexually compulsive peers, suggesting that “party n' play” may play a larger role for men with SC. In addition, the findings demonstrated empirical support for the proposition that lesbian and bisexual women with symptoms of SC were more likely to engage in specialized sexual behaviors in comparison to their non-sexually compulsive peers. These data suggest that SC manifests differently in gay, lesbian, and bisexual men and women.     

Sleep and behavioral correlates of napping among young adults: a survey of first-year university students in Madrid, Spain

Objective: Between November 2002 and March 2003, the authors assessed the prevalence and correlates of napping among Spanish university students. Participants: The sample comprised 1,276 first-year university students; the mean age was 18.74 +/- 1.24 years, and 35.45% were men. Methods: The study was cross-sectional, and the students completed self-report, anonymous questionnaires provided during an in-class survey. Results: Almost half (44%) of the sample reported napping (90% did so after lunch for longer than 1 hour). Multiple logistic regression analysis showed that experiencing an irregular sleep-wakefulness pattern, having a morning school schedule, and being male were significant predictor variables of napping. Further significant outcome variables related to napping were having excessive daytime sleepiness, missing classes because of tiredness, better ability to concentrate later in the afternoon, and a perception of deeper nighttime sleep. Conclusions: Habitual napping is common among Spanish university students and associated with an irregular sleep-wakefulness pattern. Taking long postlunch naps seems to be used by students to cope with insufficient sleep and daytime sleepiness.     

Flexible‐Duration Extended Warranties with Dynamic Reliability Learning

Frequent technological innovations and price declines adversely affect sales of extended warranties (EWs) as product replacement upon failure becomes an increasingly attractive alternative. To increase sales and profitability, we propose offering flexible‐duration EWs. These warranties can appeal to customers who are uncertain about how long they will keep the product as well as to customers who are uncertain about the product's reliability. Flexibility may be added to existing services in the form of monthly billing with month‐by‐month commitments or by making existing warranties easier to cancel with pro‐rated refunds. This paper studies flexible warranties from perspectives of both customers and the provider under customers' reliability learning. We present a model of customers' optimal coverage decisions and show that customers' optimal coverage policy has a threshold structure under some mild conditions. We further show that flexible warranties can result in higher profits and higher attach rates in a homogeneous market as well as in a heterogeneous market with multiple segments differing in various dimensions.     

Properties of Coherent Systems with Dependent Components

We introduce two new families of univariate distributions that we call hyperminimal and hypermaximal distributions. These families have interesting applications in the context of reliability theory in that they contain that of coherent system lifetime distributions. For these families, we obtain distributions, bounds, and moments. We also define the minimal and maximal signatures of a coherent system with exchangeable components which allow us to represent the system distribution as generalized mixtures (i.e., mixtures with possibly negative weights) of series and parallel systems. These results can also be applied to order statistics (k-out-of-n systems). Finally, we give some applications studying coherent systems with different multivariate exponential joint distributions.