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651.
We describe methods for assessing all possible criteria (i.e., dependent variables) and subsets of criteria for regression models with a fixed set of predictors, x (where x is an n×1 vector of independent variables). Our methods build upon the geometry of regression coefficients (hereafter called regression weights) in n-dimensional space. For a full-rank predictor correlation matrix, R xx, of order n, and for regression models with constant R 2 (coefficient of determination), the OLS weight vectors for all possible criteria terminate on the surface of an n-dimensional ellipsoid. The population performance of alternate regression weights—such as equal weights, correlation weights, or rounded weights—can be modeled as a function of the Cartesian coordinates of the ellipsoid. These geometrical notions can be easily extended to assess the sampling performance of alternate regression weights in models with either fixed or random predictors and for models with any value of R 2. To illustrate these ideas, we describe algorithms and R (R Development Core Team, 2009) code for: (1) generating points that are uniformly distributed on the surface of an n-dimensional ellipsoid, (2) populating the set of regression (weight) vectors that define an elliptical arc in ℝ n , and (3) populating the set of regression vectors that have constant cosine with a target vector in ℝ n . Each algorithm is illustrated with real data. The examples demonstrate the usefulness of studying all possible criteria when evaluating alternate regression weights in regression models with a fixed set of predictors.  相似文献   
652.
The authors proposed and tested a model in which data were collected from managers (n = 539) at 116 corporate-owned quick service restaurants to assess the structural and psychological empowerment process as moderated by shared-felt accountability on indices of performance from a managerial perspective. The authors found that empowering leadership climate positively relates to psychological empowerment climate. In turn, psychological empowerment climate relates to performance only under conditions of high-felt accountability; it does not relate to performance under conditions of low-felt accountability. Overall, the present results indicate that the quick-service restaurant managers, who feel more empowered, operate restaurants that perform better than managers who feel less empowered, but only when those empowered managers also feel a high sense of accountability.  相似文献   
653.
This paper provides an overview of theory in religion, aging, and health. It offers both a primer on theory and a roadmap for researchers. Four “tenses” of theory are described—distinct ways that theory comes into play in this field: grand theory, mid-range theory, use of theoretical models, and positing of constructs which mediate or moderate putative religious effects. Examples are given of both explicit and implicit uses of theory. Sources of theory for this field are then identified, emphasizing perspectives of sociologists and psychologists, and discussion is given to limitations of theory. Finally, reflections are offered as to why theory matters.  相似文献   
654.
In this paper I show that two arguments for the inconsistency of skeptical theism fail. After setting up the debate in “Introduction” section, I show in “The initial debate” section why Mylan Engel’s argument (Engel 2004) against skeptical theism does not succeed. In “COST” section I strengthen the argument so that it both avoids my reply to Engel and parallels Jon Laraudogoitia’s argument against skeptical theism (Laraudogoitia 2000). In “COST*” section, I provide three replies—one by an evidentialist theist, one by a closure-denying theist, and one by a necessitarian theist, and argue that the necessitarian’s reply successfully rebuts the inconsistency charge. I conclude that skeptical theism which accepts God’s necessary existence is immune to both kinds of arguments for its inconsistency.  相似文献   
655.
Even if spectrum inversion of various sorts is possible, spectrum inversion without a difference in representation is not. So spectrum inversion does not pose a challenge for the intentionalist thesis that, necessarily, within a given sense modality, if two experiences are alike with respect to content, they are also alike with respect to their phenomenal character. On the contrary, reflection on variants of standard cases of spectrum inversion provides a strong argument for intentionalism. Depending on one’s views about the possibility of spectrum inversion, the impossibility of spectrum inversion without a difference in representation can also be used as an argument against a variety of reductive theories of mental representation.  相似文献   
656.
Ecstasy has become one of the most widely used illicit drugs in Australia. This study investigated outcome expectancies as possible motivating and maintaining factors in ecstasy use and sexual risk‐taking behaviour. A sample of regular ecstasy users (N = 220) from Sydney and Canberra, Australia, was recruited for structured face‐to‐face interviews. They also completed an Ecstasy Expectancy Questionnaire. Seven of eight subscales significantly differentiated regular users from non‐users. Interestingly, light and heavier users held similar outcome expectancies, except that light users endorsed items on the sexual enhancement subscale more strongly than heavier users. Further investigation showed that the level of sexual risk taking observed in this sample was high, with the majority of participants reporting multiple partners, “casual” sexual encounters, sex under the influence of substances, and inconsistent condom use. Using logistic regression analyses, a key finding was that positive sex‐related ecstasy outcome expectancies were associated with involvement in disinhibited sexual behaviour under the influence of ecstasy. These effects persisted after statistically controlling for the frequency of ecstasy use. The findings suggest that sexual risk taking is related not only to the disinhibiting properties of ecstasy but also to beliefs that users hold about the effects of the drug.  相似文献   
657.
In a four-wave, cohort-longitudinal design with a community sample of 515 children and adolescents (grades 2 through 9), this study examined the longitudinal structure of and prospective interrelations between maladaptive cognitions and depressive symptoms. Multigroup structural equation modeling generated four major findings. First, the longitudinal structures of maladaptive cognitions and depressive symptoms consist of a single time-invariant factor and a series of time-varying factors. Second, evidence supported a model in which depressive symptoms predicted negative cognitions but not the reverse. Third, the time-invariant components of cognition and depression were highly correlated. Fourth, the strength of the depression-to-cognition relation increased with age. Implications regarding the mechanisms underlying clinical interventions with depressed children are discussed.  相似文献   
658.
The relation of interest–major congruence to indicators of college success was examined as it was moderated by environmental constraint, individual flexibility, and congruence definition in an initial sample of 88,813 undergraduates (38,787 men and 50,026 women) from 42 different colleges and universities in 16 states. College achievement (GPA after 1 semester and 2 years), persistence (enrollment status after 1 year and after 2 years) and major persistence in year 3 were used as criteria of college success. The significance of congruence (i.e., Euclidean distance and profile correlation) and its moderators above that of measures of academic achievement (i.e., ACT scores) and gender were examined for each of the college outcome criteria using hierarchical modeling. Results indicated that both the environmental constraint of the major and the interest flexibility of the individual moderated the congruence–outcome relation for both types of congruence indices. There was a greater relation between congruence and college outcomes for those majors that had more homogeneity and were more differentiated (i.e., were more constrained) than for majors where this was not true. There was a stronger relation between congruence and college outcomes for those individuals with lower overall profile levels (i.e., low flexibility) than those with high. Findings point to the importance of interest–major congruence in the college outcome process, but also highlight the complexity of the congruence–outcome relation.  相似文献   
659.
The forcefulness of key press responses was measured in stop-all and selective stopping versions of the stop-signal paradigm. When stop signals were presented too late for participants to succeed in stopping their responses, response force was nonetheless reduced relative to trials in which no stop signal was presented. This effect shows that peripheral motor aspects of primary task responses can still be influenced by inhibition even when the stop signal arrives too late to prevent the response. It thus requires modification of race models in which responses in the presence of stop signals are either stopped completely or produced normally, depending on whether the responding or stopping process finishes first.  相似文献   
660.
Investigate factors that amplify or mitigate the effects of an indicated cognitive behavioral (CB) depression prevention program for adolescents with elevated depressive symptoms. Using data from a randomized trial (Registration No. NCT00183417; n?=?173) in which adolescents (M age =?15.5, SD =?1.2) were assigned to a brief cognitive behavioral prevention program or an educational brochure control condition, we tested whether elevated motivation to reduce depression and initial depressive symptom severity amplified intervention effects and whether negative life events, social support deficits, and substance use attenuated intervention effects. Hierarchical linear modeling (HLM) indicated differential intervention effects for two of the five examined variables: negative life events and substance use. For adolescents at low and medium levels of substance use or negative life events, the CB intervention produced declines in depressive symptoms relative to controls. However, at high levels of substance use or negative life events, the CB intervention did not significantly reduce depressive symptoms in comparison to controls. Results imply that high-risk adolescents with either high rates of major life stress or initial substance use may require specialized depression prevention efforts.  相似文献   
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