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71.
Religiosity is associated with behaviors that reduce the risk of HIV/STI infection among general-population and heterosexual-specific samples. Whether this association is similar to homosexual persons is unknown. Measures of religiosity have not been evaluated psychometrically among men who have sex with men (MSM), a population who, because of stigma, experience religiosity differently than heterosexual persons. We assessed the duke religion index and the spiritual well-being in two samples of MSM. Neither instrument produced adequate model fit. To study the association between religiosity and HIV/STI risk behaviors among MSM, scales are needed that measure the religious and spiritual experiences of MSM.  相似文献   
72.
Abstract

Conventional growth models assume that the random effects describing individual trajectories are conditionally normal. In practice, this assumption may often be unrealistic. As an alternative, Nagin (2005) Nagin, D. 2005. Group-based modeling of development, Cambridge: Harvard University Press. [Crossref] [Google Scholar] suggested a semiparametric group-based approach (SPGA) which approximates an unknown, continuous distribution of individual trajectories with a mixture of group trajectories.

Prior simulations (Brame, Nagin, &; Wasserman, 2006 Brame, R., Nagin, D. and Wasserman, L. 2006. Exploring some analytical characteristics of finite mixture models.. Journal of Quantitative Criminology, 22: 3159. [Crossref], [Web of Science ®] [Google Scholar]; Nagin, 2005 Nagin, D. 2005. Group-based modeling of development, Cambridge: Harvard University Press. [Crossref] [Google Scholar]) indicated that SPGA could generate nearly-unbiased estimates of means and variances of a nonnormal distribution of individual trajectories, as functions of group-trajectory estimates. However, these studies used few random effects—usually only a random intercept. Based on the analytical relationship between SPGA and adaptive quadrature, we hypothesized that SPGA's ability to approximate (a) random effect variances/covariances and (b) effects of time-invariant predictors of growth should deteriorate as the dimensionality of the random effects distribution increases. We expected this problem to be mitigated by correlations among the random effects (highly correlated random effects functioning as fewer dimensions) and sample size (larger N supporting more groups).

We tested these hypotheses via simulation, varying the number of random effects (1, 2, or 3), correlation among the random effects (0 or .6), and N (250, 500). Results indicated that, as the number of random effects increased, SPGA approximations remained acceptable for fixed effects, but became increasingly negatively biased for random effect variances. Whereas correlated random effects and larger N reduced this underestimation, correlated random effects sometimes distorted recovery of predictor effects. To illustrate this underestimation, Figure 1 depicts SPGA's approximation of the intercept variance from a three correlated random effect generating model (N < eqid1 > 500). These results suggest SPGA approximations are inadequate for the nonnormal, high-dimensional distributions of individual trajectories often seen in practice.
FIGURE 1 SPGA-approximated intercept variance from a three correlated random effect generating model. Notes. The dashed horizontal lines denote + 10% bias. The solid horizontal line denotes the population-generating parameter value; * denotes the best-BIC selected number of groups. The vertical bars denote 90% confidence intervals.  相似文献   
73.
A randomized prevention trial was conducted contrasting families who took part in the Strong African American Families Program (SAAF), a preventive intervention for rural African American parents and their 11-year-olds, with control families. The trial, which included 671 families, indicated that intervention-induced changes occurred in intervention-targeted parenting and youth behavior, as well as youth initiation of alcohol use and sexual activity. Four waves of data collected were obtained at pretest, 3-month post-test, 29 month long-term follow up; and 65 month long-term follow up. Three data points were selected and analyzed in the current study: pretest, post-test, and 65 month long-term follow up to capture the sustainability of SAAF during three critical developmental stages—middle childhood, early adolescence, and late adolescence. Intervention-induced changes in parenting mediated the effect of intervention-group influences on changes in the onset and escalation of alcohol use and sexual activity over 65 months through its positive influence on youths’ perceptions and internalization of parental norms and resistance to engaging in risk opportunities. These findings highlight the potential for family-based prevention programs to enhance positive developmental outcomes to reduce HIV-related risk behaviors among rural African American youth.  相似文献   
74.
In this article, we discuss decision making during labor and delivery, specifically focusing on decision making around offering women a trial of labor after cesarean section (TOLAC). Many have discussed how humans are notoriously bad at assessing risks and how we often distort the nature of various risks surrounding childbirth. We will build on this discussion by showing that physicians make decisions around TOLAC not only based on distortions of risk, but also based on personal values (i.e. what level of risk are you comfortable with or what types of risks are you willing to take) rather than medical data (or at least medical data alone). As a result of this, we will further suggest that the party who is best epistemically situated to make decisions about TOLAC is the woman herself.  相似文献   
75.
The present online survey study (Amazon’s MTurk; n = 371) investigated links between three different social self-concepts (the need to belong, narcissism, and relatedness) and the appeal of fame. We examined fame attitudes using a newly-devised fame appeal scale (yielding three factors: Visibility, Status and Prosocial), as well as with two items probing frequency of fame fantasizing and perceived realism of becoming famous. Results show that higher belongingness needs were associated with increased appeal of all three fame factors, as well as increased frequency of fantasizing about fame (accounting for age and gender). Narcissism was associated with increased appeal of Visibility and Status, more time spent engaged in fame fantasy, and greater perceived realism of future fame. Finally, Relatedness predicted increased appeal of the Prosocial fame factor only. Findings illuminate the socioemotional underpinnings of fame appeal and the individual differences that may render certain aspects of fame particularly alluring.  相似文献   
76.
Sex Roles - We assessed developmental and gender differences in children’s beliefs about their peers’ communication styles. We hypothesized that children hold more favorable beliefs...  相似文献   
77.
Posttraumatic stress disorder (PTSD) symptoms and poor sleep have been identified as potential causals factor in aggression, violence, and impulsive behavior. Given the high cost of aggression to society and public health, identifying modifiable factors related to aggression, such as insomnia, may guide treatment strategies to help decrease aggression. Participants were 143 Veterans seeking treatment for PTSD at a VA outpatient PTSD clinic. Linear and logistic regression analyses were used to examine the relation between PTSD and insomnia on aggression. Results from bivariate analyses indicated that while both PTSD and insomnia severity were associated with higher aggression scores independently, when PTSD and insomnia were examined together, PTSD severity was the only significant predictor of aggression. Interaction effects yielded nonsignificant results suggesting that poor sleep did not moderate the PTSD and aggression relation. Results suggest that addressing PTSD symptoms as a first treatment target may be more important for decreasing risk for aggression than targeting insomnia. More research is needed to understand whether treating PTSD and insomnia reduces aggression in Veterans.  相似文献   
78.
In 5 experiments, the authors investigated how listeners learn to recognize unfamiliar talkers and how experience with specific utterances generalizes to novel instances. Listeners were trained over several days to identify 10 talkers from natural, sinewave, or reversed speech sentences. The sinewave signals preserved phonetic and some suprasegmental properties while eliminating natural vocal quality. In contrast, the reversed speech signals preserved vocal quality while distorting temporally based phonetic properties. The training results indicate that listeners learned to identify talkers even from acoustic signals lacking natural vocal quality. Generalization performance varied across the different signals and depended on the salience of phonetic information. The results suggest similarities in the phonetic attributes underlying talker recognition and phonetic perception.  相似文献   
79.
Multilevel data structures are common in the social sciences. Often, such nested data are analysed with multilevel models (MLMs) in which heterogeneity between clusters is modelled by continuously distributed random intercepts and/or slopes. Alternatively, the non‐parametric multilevel regression mixture model (NPMM) can accommodate the same nested data structures through discrete latent class variation. The purpose of this article is to delineate analytic relationships between NPMM and MLM parameters that are useful for understanding the indirect interpretation of the NPMM as a non‐parametric approximation of the MLM, with relaxed distributional assumptions. We define how seven standard and non‐standard MLM specifications can be indirectly approximated by particular NPMM specifications. We provide formulas showing how the NPMM can serve as an approximation of the MLM in terms of intraclass correlation, random coefficient means and (co)variances, heteroscedasticity of residuals at level 1, and heteroscedasticity of residuals at level 2. Further, we discuss how these relationships can be useful in practice. The specific relationships are illustrated with simulated graphical demonstrations, and direct and indirect interpretations of NPMM classes are contrasted. We provide an R function to aid in implementing and visualizing an indirect interpretation of NPMM classes. An empirical example is presented and future directions are discussed.  相似文献   
80.
Results of functional analyses for 36 individuals whose self-injurious behavior (SIB) was maintained by attention indicated that SIB was highest during a condition in which the individual was deprived of attention (establishing operation) except as a consequence (reinforcer). Deprivation in the absence of reinforcement produced marginal increases in SIB in 5 individuals, and a relatively rich schedule of noncontingent attention produced the lowest levels of SIB. These results suggest that clearer functional analysis outcomes are likely to be obtained when test conditions contain both an establishing operation to evoke behavior as well as a reinforcement contingency to maintain it.  相似文献   
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