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211.
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   
212.
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   
213.
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   
214.
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   
215.
Toddlers often display problem behavior during transitions. We rearranged naturally occurring events in a toddler classroom to promote more desirable classroom behavior during transitions to meals. In the intervention condition, teachers transitioned each child to meals only when that child was seated on a play mat (a requisite for engagement in teacher‐led play activities). In the reversal condition, teachers selected each child to transition when that child was by the barrier to the meal area (a practice commonly observed under natural conditions). The intervention increased the mean percentage of intervals when children were on the play mat and decreased the percentage of intervals when children were by the barrier. Individual child data show positive outcomes for five of six children. Results are discussed in terms of the positive effects of small manipulations to existing contingencies on classroom behavior as well as their potential influence on the adoptability of classroom interventions. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
216.
The current study examined the function of expressive suppression among Chinese rescue medical staff following a major earthquake. We administered self‐report questionnaires to (1) a sample of Chinese hospital medical staff (n = 305) who assisted victims of the Sichuan earthquake, and (2) a second sample of Chinese hospital medical staff (n = 149) who had not been exposed to a major stressor. To examine possible interaction effects among differing emotion regulation strategies, we also conducted structured interviews with a subset of rescue medical staff to obtain support for a positive function of expressive suppression and a mediating role of positive reappraisal. Structural equation modelling indicated that expressive suppression was associated with higher levels of job engagement and lower levels of job burnout among the rescue medical staff and that these effects were mediated by positive reappraisal. However, for regular medical staff (not exposed to traumatic stress), expressive suppression was associated with higher levels of both job engagement and job burnout; these effects were mediated by acceptance. These results provide preliminary evidence for the positive role of expressive suppression within Chinese culture.  相似文献   
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219.
In this paper I present an interpretation of J. G. Fichte's transcendental argument for the necessity of mutual recognition (Anerkennung) in Foundations of Natural Right. Fichte's argument purports to show that, as a condition of the possibility of self‐consciousness, we must take ourselves to stand in relations of mutual recognition with other agents like ourselves. After reconstructing the steps of Fichte's argument, I present what I call the ‘modal dilemma’, which highlights a serious ambiguity in Fichte's deduction. According to the modal dilemma, the conclusion to Fichte's transcendental argument—that as a condition of the possibility of our self‐consciousness, we must recognize and be recognized by others—expresses either metaphysical or normative necessity. However, no normative conclusion follows from Fichte's premises, and the metaphysical claim that does follow from his argument appears to be implausibly strong. Thus the argument looks like a failure on either interpretation of the conclusion's modality. In the penultimate section of the paper, I propose a new interpretation of the argument that avoids the modal dilemma and provides a normative grounding of Fichte's concept of right.  相似文献   
220.
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   
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