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921.
Our goal is to provide empirical scientists with practical tools and advice with which to test hypotheses related to individual differences in intra-individual variability using the mixed-effects location-scale model. To that end, we evaluate Type I error rates and power to detect and predict individual differences in intra-individual variability using this model and provide empirically-based guidelines for building scale models that include random and/or systematically-varying fixed effects. We also provide two power simulation programs that allow researchers to conduct a priori empirical power analyses. Our results aligned with statistical power theory, in that, greater power was observed for designs with more individuals, more repeated occasions, greater proportions of variance available to be explained, and larger effect sizes. In addition, our results indicated that Type I error rates were acceptable in situations when individual differences in intra-individual variability were not initially detectable as well as when the scale-model individual-level predictor explained all initially detectable individual differences in intra-individual variability. We conclude our paper by providing study design and model building advice for those interested in using the mixed-effects location-scale model in practice.  相似文献   
922.
Process factor analysis (PFA) is a latent variable model for intensive longitudinal data. It combines P-technique factor analysis and time series analysis. The goodness-of-fit test in PFA is currently unavailable. In the paper, we propose a parametric bootstrap method for assessing model fit in PFA. We illustrate the test with an empirical data set in which 22 participants rated their effects everyday over a period of 90 days. We also explore Type I error and power of the parametric bootstrap test with simulated data.  相似文献   
923.
Latent change score models (LCS) are conceptually powerful tools for analyzing longitudinal data (McArdle & Hamagami, 2001). However, applications of these models typically include constraints on key parameters over time. Although practically useful, strict invariance over time in these parameters is unlikely in real data. This study investigates the robustness of LCS when invariance over time is incorrectly imposed on key change-related parameters. Monte Carlo simulation methods were used to explore the impact of misspecification on parameter estimation, predicted trajectories of change, and model fit in the dual change score model, the foundational LCS. When constraints were incorrectly applied, several parameters, most notably the slope (i.e., constant change) factor mean and autoproportion coefficient, were severely and consistently biased, as were regression paths to the slope factor when external predictors of change were included. Standard fit indices indicated that the misspecified models fit well, partly because mean level trajectories over time were accurately captured. Loosening constraint improved the accuracy of parameter estimates, but estimates were more unstable, and models frequently failed to converge. Results suggest that potentially common sources of misspecification in LCS can produce distorted impressions of developmental processes, and that identifying and rectifying the situation is a challenge.  相似文献   
924.
According to behavioral momentum theory (Nevin & Grace, 2000a), preference in concurrent chains and resistance to change in multiple schedules are independent measures of a common construct representing reinforcement history. Here I review the original studies on preference and resistance to change in which reinforcement variables were manipulated parametrically, conducted by Nevin, Grace and colleagues between 1997 and 2002, as well as more recent research. The cumulative decision model proposed by Grace and colleagues for concurrent chains is shown to provide a good account of both preference and resistance to change, and is able to predict the increased sensitivity to reinforcer rate and magnitude observed with constant‐duration components. Residuals from fits of the cumulative decision model to preference and resistance to change data were positively correlated, supporting the prediction of behavioral momentum theory. Although some questions remain, the learning process assumed by the cumulative decision model, in which outcomes are compared against a criterion that represents the average outcome value in the current context, may provide a plausible model for the acquisition of differential resistance to change.  相似文献   
925.
本研究以226名学前儿童和其父母为研究对象,从儿童气质-家庭环境交互作用的视角,采用父母报告的方法收集数据,考察了父母心理控制及儿童消极情绪性对儿童问题行为的共同作用。结果发现:在预测外化问题时,父亲和母亲心理控制的主效应均显著,同时父亲心理控制与儿童消极情绪性的交互作用也显著。显著性区域分析发现,高消极情绪性的学前儿童更易受高父亲心理控制的不利影响,也更易受低父亲心理控制的有利影响,该结果支持差别易感性模型;在预测内化问题时,父亲和母亲心理控制的主效应及其与儿童消极情绪性的交互作用均不显著,说明无论是对高消极情绪性还是低消极情绪性儿童,父母心理控制对其内化问题的影响相对较弱。  相似文献   
926.
为探讨地方政府政策执行偏差严重程度对公众地方政府责任判断的影响机制。采用问卷法对678名社会公众进行调查,结果显示:(1)地方政府政策执行偏差情境下,公众地方政府愿望判断和公众地方政府信念判断在政策执行偏差严重程度和公众地方政府责任判断之间起多重中介作用。(2)公众地方政府信念判断在政策执行偏差严重程度和公众地方政府责任判断之间的中介效应量大于公众地方政府愿望判断的中介效应量。  相似文献   
927.
Background and objectives: For decades, the dominant paradigm in trait anxiety research has regarded the construct as signifying the underlying cause of the thoughts, feelings, and behaviors that supposedly reflect its presence. Recently, a network theory of personality has appeared. According to this perspective, trait anxiety is a formative construct emerging from interactions among its constitutive features (e.g., thought, feelings, behaviors); it is not a latent cause of these features.

Design: In this study, we characterized trait anxiety as a network system of interacting elements.

Methods: To do so, we estimated a graphical gaussian model via the computation of a regularized partial correlation network in an unselected sample (N?=?611). We also implemented modularity-based community detection analysis to test whether the features of trait anxiety cohere as a single network system.

Results: We find that trait anxiety can indeed be conceptualized as a single, coherent network system of interacting elements.

Conclusions: This radically new approach to visualizing trait anxiety may offer an especially informative view of the interplay between its constitutive features. As prior research has implicated trait anxiety as a risk factor for the development of anxiety-related psychopathology, our findings also set the scene for novel research directions.  相似文献   
928.
The fourteen-factor Processes of Change Scale for Sun Protection assesses behavioral and experiential strategies that underlie the process of sun protection acquisition and maintenance. Variations of this measure have been used effectively in several randomized sun protection trials, both for evaluation and as a basis for intervention. However, there are no published studies, to date, that evaluate the psychometric properties of the scale. The present study evaluated factorial invariance and scale reliability in a national sample (N = 1360) of adults involved in a Transtheoretical model tailored intervention for exercise and sun protection, at baseline. Invariance testing ranged from least to most restrictive: Configural Invariance (constraints only factor structure and zero loadings); Pattern Identity Invariance (equal factor loadings across target groups); and Strong Factorial Invariance (equal factor loadings and measurement errors). Multi-sample structural equation modeling tested the invariance of the measurement model across seven subgroups: age, education, ethnicity, gender, race, skin tone, and Stage of Change for Sun Protection. Strong factorial invariance was found across all subgroups. Internal consistency coefficient Alpha and factor rho reliability, respectively, were .83 and .80 for behavioral processes, .91 and .89 for experiential processes, and .93 and .91 for the global scale. These results provide strong empirical evidence that the scale is consistent, has internal validity and can be used in research interventions with population-based adult samples.  相似文献   
929.
The present study aimed to investigate the prevalence of fatigue and determine factors associated with fatigue in female medical personnel. Based on a cross-sectional study, a total of 1608 female medical personnel at 54 hospitals in Zhuhai, China were recruited by a multistage stratified cluster sampling method. The Symptoms Checklist-90-Revised and Chalder Fatigue Scale were used to assess psychiatric symptoms and fatigue, respectively. Data regarding demographic, health, and work related variables were also collected. Multivariate logistic regression model was constructed to determine the influencing factors of fatigue. Approximately 83% of participants had experienced fatigue in the past week. The risk of fatigue was higher in aged 30–39 years old than older or younger participants; Longer sleeping time predicted a lower prevalence of fatigue (OR = .35), while tense physician-patient relationship predicted a higher prevalence of fatigue (OR = 1.77). Depression (OR = 1.76) and anxiety (OR = 1.96) were found related to fatigue. Additionally, fatigue was associated with marital status, occupation, health related factors (exercise, regular diet, and health status), and work related factors (hospital rank and turnover intention). These study findings might facilitate development and implementation of targeted interventions and preventive measures.  相似文献   
930.
Work environments characterized by inadequate work conditions have been widely recognized as being particularly prone to the occurrence and exacerbation of bullying behavior. Accordingly, this longitudinal study aimed to explore whether the impact of effort–reward imbalance (ERI) on workplace bullying was mediated by a lower perception of organizational justice, and whether the association between ERI and perceptions of justice was moderated by organizational identification. In the current study, a sample of N = 195 Spanish employees from different occupational sectors filled in an online questionnaire at two different times with a time lag of 8 months. In line with the hypothesized moderated mediation model, results showed that organizational justice mediated the impact of ERI on workplace bullying. Moreover, the effect of perceived ERI on organizational justice was stronger for employees with low organizational identification. Overall, this study can contribute to better understanding how and when ERI boosts the risk of workplace bullying. Accordingly, early intervention designed to buffer the negative effects of ERI should focus on increasing individual levels of organizational identification.  相似文献   
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