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1.
Explaining group-level outcomes from individual-level predictors requires aggregating the individual-level scores to the group level and correcting the group-level estimates for measurement errors in the aggregated scores. However, for discrete variables it is not clear how to perform the aggregation and correction. It is shown how stepwise latent class analysis can be used to do this. First, a latent class model is estimated in which the scores on a discrete individual-level predictor are used to construct group-level latent classes. Second, this latent class model is used to aggregate the individual-level predictor by assigning the groups to the latent classes. Third, a group-level analysis is performed in which the aggregated measures are related to the remaining group-level variables while correcting for the measurement error in the class assignments. This stepwise approach is introduced in a multilevel mediation model with a single individual-level mediator, and compared to existing methods in a simulation study. We also show how a mediation model with multiple group-level latent variables can be used with multiple individual-level mediators and this model is applied to explain team productivity (group level) as a function of job control (individual level), job satisfaction (individual level), and enriched job design (group level).  相似文献   

2.
This research examines the relationships between top management and supervisory ethical leadership and group-level outcomes (e.g., deviance, OCB) and suggests that ethical leadership flows from one organizational level to the next. Drawing on social learning theory [Bandura, A. (1977). Social learning theory. Englewood Cliffs, NJ: Prentice-Hall.; Bandura, A. (1986). Social foundations of thought and action. Englewood Cliffs, NJ: Prentice-Hall.] and social exchange theory [Blau, p. (1964). Exchange and power in social life. New York: John Wiley.], the results support our theoretical model using a sample of 904 employees and 195 managers in 195 departments. We find a direct negative relationship between both top management and supervisory ethical leadership and group-level deviance, and a positive relationship with group-level OCB. Finally, consistent with the proposed trickle-down model, the effects of top management ethical leadership on group-level deviance and OCB are mediated by supervisory ethical leadership.  相似文献   

3.
A review and critique of the literature pertaining to the use of cognitive remediation techniques in patients with schizophrenia is presented. The review is organized into three sections, according to the neuropsychological deficit targeted for remediation: 1) executive-function, 2) attention, and 3) memory. With regards to executive-function, despite an initial report suggesting that Wisconsin Card Sorting Test performance cannot be remediated, subsequent studies suggest that performance can be improved on a variety of dependent measures including perseverative errors, categories achieved, and conceptual level responses. These observations were confirmed by a meta-analytic investigation that revealed large mean effects sizes (d + = 0.96) for these studies. Effect sizes were homogenous across discrepant remediation strategies and dependent measures. With regards to attention, serial scanning can be improved with instruction and reinforcement, whereas there is mixed evidence suggesting that practice-based attention drills can improve performance on measures of sustained attention in schizophrenia. With regards to memory, relatively simple semantic and affective elaborate encoding strategies elevates verbal list-learning memory in patients with schizophrenia to levels consistent with controls. A similar encoding procedure, combined with vigilance training, produces substantial improvement in social cue recognition. Avenues for future research are discussed.  相似文献   

4.
Background. Verbal learning and memory is often compromised in patients with schizophrenia who prefer encoding words in order of their presentation (serial clustering) rather than using semantic categories (semantic clustering). Method. One hundred and four in‐patients with schizophrenia were assessed twice with the California Verbal Learning Test. Results. Patients showed significantly less semantic than serial clustering at both assessment times. Usage of encoding strategies were not stable over time. An increase in semantic clustering improved recall and recognition performance. Conclusions. Patients with schizophrenia should be taught to use the more effective encoding strategy of semantic clustering in order to improve their memory performance.  相似文献   

5.
Multilevel analyses are often used to estimate the effects of group-level constructs. However, when using aggregated individual data (e.g., student ratings) to assess a group-level construct (e.g., classroom climate), the observed group mean might not provide a reliable measure of the unobserved latent group mean. In the present article, we propose a Bayesian approach that can be used to estimate a multilevel latent covariate model, which corrects for the unreliable assessment of the latent group mean when estimating the group-level effect. A simulation study was conducted to evaluate the choice of different priors for the group-level variance of the predictor variable and to compare the Bayesian approach with the maximum likelihood approach implemented in the software Mplus. Results showed that, under problematic conditions (i.e., small number of groups, predictor variable with a small ICC), the Bayesian approach produced more accurate estimates of the group-level effect than the maximum likelihood approach did.  相似文献   

6.
Recent developments in personality research highlight the value of modelling dynamic state-like manifestations of personality. The present work integrates these developments with prominent clinical models addressing within-person multiplicity and promotes the exploration of models centred on state-like manifestations of personality that function as cohesive organizational units. Such units possess distinct subjective qualities and are characterized by specific affects, behaviours, cognitions, and desires that tend to be co-activated. As background, we review both theory and research from the fields of social cognition, psychotherapy, and psychopathology that serve as the foundation for such models. We then illustrate our ideas in greater detail with one well-supported clinical model—the schema therapy mode model, chosen because it provides a finite and definite set of modes (i.e. cohesive personality states). We assessed these modes using a newly developed experience-sampling measure administered to 52 individuals (four times daily for 15 days). We estimated intraindividual and group-level temporal and contemporaneous networks based on the within-person variance as well as between-person network. We discuss findings from exemplar participants and from group-level networks and address cross-model particularities and consistencies. In conclusion, we consider potential idiographic and nomothetic applications of subjective states dynamic personality research based on intensive longitudinal methods. © 2020 European Association of Personality Psychology  相似文献   

7.
Abstract

An experiment was conducted to examine the effects of levels of naturally occurring dysphoria and elaborative encoding on recall. Previous research has indicated that the facilitative effects of elaborative encoding on recall are reduced by the induction of negative moods in laboratory settings. However, the effects of endogenous dysphoria on recall are less clear. In the present study, 82 subjects from a college population were categorised as dysphoria or nondysphoric on the basis of two self-report measures. They were then presented with sentences in both elaborated and nonelaborated form, and recall for target words embedded in the sentences was assessed. Results demonstrated that nondysphoric individuals benefited from elaborative encoding in recall performance, whereas dysphoric individuals did not. Results are discussed in terms of Ellis and Ashbrook's (1988) resource allocation model of depression.  相似文献   

8.
张珊珊  张建新 《心理科学》2014,37(1):140-145
基于领导-团队匹配的视角,研究以133名领导和645名成员的团队配对数据,采用二次多项式回归与响应面分析对领导工作投入与团队投入氛围的一致性匹配和不一致性匹配,以及团队满意度氛围如何影响团队绩效进行了探讨。结果发现:领导工作投入与团队投入氛围一致与不一致相比,团队绩效较好;并且一致性匹配具有加强效应,即当领导工作投入与团队投入氛围一致时,团队绩效随着双方投入的增加而提高;同时,团队满意度氛围在领导-团队投入的一致性匹配与团队绩效的线性关系中起到部分中介作用。  相似文献   

9.
This paper examines relationships between human resource management (HRM), work climate, and organizational performance in the branch network of a retail bank. It extends previous research on group-level climate-performance and HRM-performance relationships and examines how climate and HRM function as joint antecedents of business unit performance. Significant correlations are found between work climate, human resource practices, and business performance. The results show that the correlations between climate and performance cannot be explained by their common dependence on HRM factors, and that the data are consistent with a mediation model in which the effects of HRM practices on business performance are partially mediated by work climate.  相似文献   

10.
Working memory (WM) impairment is a core feature of schizophrenia, but the contributions of different WM components are not yet specified. Here, we investigated the potential role of inefficient encoding in reduced WM performance in patients with schizophrenia (PSZ). Twenty-eight PSZ, 16 patients with bipolar disorder (PBP), 16 unaffected and unmedicated relatives of PSZ (REL), and 29 demographically matched healthy controls (HC) performed a spatial delayed response task with either low or high WM demands. The demands on attentional selection were also manipulated by presenting distractor stimuli during encoding in some of the trials. After each trial, participants rated their level of response confidence. This allowed us to analyze different types of WM responses. WM was severely impaired in PSZ compared to HC; this reduction was mainly due to an increase in the amount of false memory responses (incorrect responses that were given with high confidence) rather than an increase in the amount of incorrect and not-confident responses. Although PBP showed WM impairments, they did not have increased false memory errors. In contrast, reduced WM in REL was also accompanied by an increase in false memory errors. The presentation of distractors led to a decline in WM performance, which was comparable across groups indicating that attentional selection was intact in PSZ. These findings suggest that inefficient WM encoding is responsible for impaired WM in schizophrenia and point to differential mechanisms underlying WM impairments in PSZ and PBP. (PsycINFO Database Record (c) 2012 APA, all rights reserved).  相似文献   

11.
Two models for the analysis of longitudinal binary data are discussed: the marginal model and the random intercepts model. In contrast to the linear mixed model (LMM), the two models for binary data are not subsumed under a single hierarchical model. The marginal model provides group-level information whereas the random intercepts model provides individual-level information including information about heterogeneity of growth. It is shown how a type of numerical averaging can be used with the random intercepts model to obtain group-level information, thus approximating individual and marginal aspects of the LMM. The types of inferences associated with each model are illustrated with longitudinal criminal offending data based on N = 506 males followed over a 22-year period. Violent offending indexed by official records and self-report were analyzed, with the marginal model estimated using generalized estimating equations and the random intercepts model estimated using maximum likelihood. The results show that the numerical averaging based on the random intercepts can produce prediction curves almost identical to those obtained directly from the marginal model parameter estimates. The results provide a basis for contrasting the models and the estimation procedures and key features are discussed to aid in selecting a method for empirical analysis.  相似文献   

12.
Verbal declarative memory is one of the most reliably impaired cognitive functions in schizophrenia. Important issues are whether the problem is reversible, and which brain regions underlie improvement. We showed previously that glucose administration improved declarative memory in patients with schizophrenia, and sought in this pilot study to identify whether glucose affects the location or degree of activation of brain regions involved in a verbal encoding task. Seven clinically stable and medicated patients with schizophrenia or schizoaffective disorder, who showed deficits on a clinical test of memory, participated in the study. Subjects served as their own controls in a double-blind, crossover protocol that consisted of two sessions about a week apart. In each session, subjects ingested a beverage flavored with lemonade that contained 50 g of glucose on one occasion, and saccharin on the other. Blood glucose was measured before and 15, 50, and 75 min after ingestion. After ingesting the beverage, they performed a verbal encoding task while undergoing brain functional magnetic resonance imaging. The results showed significantly greater activation of the left parahippocampus during novel sentence encoding in the glucose condition, compared to the saccharin condition, despite no change in memory performance. A trend towards greater activation of the left dorsolateral prefrontal cortex (p<.07) was also evident in the glucose condition. These pilot findings emphasize the sensitivity of both the medial temporal and prefrontal regions to effects of glucose administration during encoding, and are consistent with the hypothesis that these regions also participate in declarative memory improvements following glucose administration.  相似文献   

13.
Working memory impairments in schizophrenia: a meta-analysis   总被引:12,自引:0,他引:12  
Working memory (WM) deficit is a cardinal cognitive symptom of schizophrenia, but the differences among the tasks and measures used to assess WM make it difficult to compare across studies. The authors conducted a meta-analytic review to address 3 major questions: (a) Do patients with schizophrenia show WM deficits across diverse methodology; (b) Is WM deficit supramodal; and (c) Does the WM deficit worsen with longer delays? The results indicate that significant WM deficit was present in schizophrenia patients in all modalities examined. Increasing delay beyond 1 s did not influence the performance difference between schizophrenia patients and healthy control participants in WM. These results suggest that WM deficit in schizophrenia is modality independent and that encoding and/or early part of maintenance may be problematic.  相似文献   

14.
Empirical work and models of visual word recognition have traditionally focused on group-level performance. Despite the emphasis on the prototypical reader, there is clear evidence that variation in reading skill modulates word recognition performance. In the present study, we examined differences among individuals who contributed to the English Lexicon Project (http://elexicon.wustl.edu), an online behavioral database containing nearly 4 million word recognition (speeded pronunciation and lexical decision) trials from over 1,200 participants. We observed considerable within- and between-session reliability across distinct sets of items, in terms of overall mean response time (RT), RT distributional characteristics, diffusion model parameters (Ratcliff, Gomez, & McKoon, 2004), and sensitivity to underlying lexical dimensions. This indicates reliably detectable individual differences in word recognition performance. In addition, higher vocabulary knowledge was associated with faster, more accurate word recognition performance, attenuated sensitivity to stimuli characteristics, and more efficient accumulation of information. Finally, in contrast to suggestions in the literature, we did not find evidence that individuals were trading-off their utilization of lexical and nonlexical information.  相似文献   

15.
The present study investigated how individual- and group-level psychological need satisfaction ( Deci & Ryan, 1985a ) influence affect, intrinsic motivation, and performance satisfaction. It also examined the impact of leader personality on group need satisfaction. Groups (45) of 4 college women participated in a task, with 1 member designated "leader." Multilevel modeling revealed significant between- and within- groups relations. Individuals in groups with higher need satisfaction reported greater pleasant affect, intrinsic motivation, and satisfaction with group performance. In addition, individuals whose need satisfaction was higher than their group's average reported greater intrinsic motivation, pleasant affect, and performance satisfaction. Group need satisfaction was found to be lower under neurotic leaders and higher under agreeable, introverted leaders. Implications for group environments are discussed.  相似文献   

16.
Schizophrenia may be associated with a fundamental disturbance in the temporal coordination of information processing in the brain, leading to classic symptoms of schizophrenia such as thought disorder and disorganized and contextually inappropriate behavior. Although a variety of behavioral studies have provided strong evidence for perceptual timing deficits in schizophrenia, no study to date has directly examined overt temporal performance in schizophrenia using a task that differentially engages perceptual and motor-based timing processes. The present study aimed to isolate perceptual and motor-based temporal performance in individuals diagnosed with schizophrenia using a repetitive finger-tapping task that has previously been shown to differentially engage brain regions associated with perceptual and motor-related timing behavior. Thirty-two individuals with schizophrenia and 31 non-psychiatric control participants completed the repetitive finger-tapping task, which required participants to first tap in time with computer-generated tones separated by a fixed intertone interval (tone-paced tapping), after which the tones were discontinued and participants were required to continue tapping at the established pace (self-paced tapping). Participants with schizophrenia displayed significantly faster tapping rates for both tone- and self-paced portions of the task compared to the non-psychiatric group. Individuals diagnosed with schizophrenia also displayed greater tapping variability during both tone- and self-paced portions of the task. The application of a mathematical timing model further indicated that group differences were primarily attributable to increased timing – as opposed to task implementation – difficulties in the schizophrenia group, which is noteworthy given the broad range of impairments typically associated with the disorder. These findings support the contention that schizophrenia is associated with a broad range of timing difficulties, including those associated with time perception as well as time production.  相似文献   

17.
Schizophrenia may be associated with a fundamental disturbance in the temporal coordination of information processing in the brain, leading to classic symptoms of schizophrenia such as thought disorder and disorganized and contextually inappropriate behavior. Despite the growing interest and centrality of time-dependent conceptualizations of the pathophysiology of schizophrenia, there remains a paucity of research directly examining overt timing performance in the disorder. Accordingly, the present study investigated timing in schizophrenia using a well-established task of time perception. Twenty-three individuals with schizophrenia and 22 non-psychiatric control participants completed a temporal bisection task, which required participants to make temporal judgments about auditory and visually presented durations ranging from 300 to 600 ms. Both schizophrenia and control groups displayed greater visual compared to auditory timing variability, with no difference between groups in the visual modality. However, individuals with schizophrenia exhibited less temporal precision than controls in the perception of auditory durations. These findings correlated with parameter estimates obtained from a quantitative model of time estimation, and provide evidence of a fundamental deficit in temporal auditory precision in schizophrenia.  相似文献   

18.

Purpose

In this investigation, we argue for why and how available intraclass correlation coefficients and other types of reliability estimates can be employed as sample-based reliability estimates within primary and meta-analytic studies when relationships between group-level phenomena are of interest.

Design/Methodology/Approach

Group-level correlations and reliability estimates were obtained from 46 studies examining organizational climate–performance relationships. We illustrate how the group-level reliability estimates can be used to correct correlations for predictor and criterion unreliability. Procedures are presented for computing the sampling variances of individually corrected correlations that account for sampling error in the group-level reliability estimates.

Findings

Support was found for the conservative nature of meta-analytic parameter estimates when group-level reliability information is sample-based as opposed to assumed population values. In addition, our analyses indicated that conclusions about substantive relationships between group-level variables can change based on availability of sample-based reliabilities within both primary and meta-analytic studies.

Implications

Results from this study suggest that researchers should rely on sample-based meta-analytic procedures when examining the generalizability of group-level relationships. This study also demonstrates the importance of using all available reliability information and accounting for sampling error in the reliability estimates when conducting meta-analyses at the group level of analysis.

Originality/Value

This study breaks ground by systematically examining the use of intraclass correlation coefficients as reliability estimates within group-level meta-analytic studies. Furthermore, illustrative analyses provide guidance to primary and meta-analytic researchers in regard to how to correct group-level correlations for unreliability in the predictor, criterion, or both whenever and in whatever proportions the artifact information is available.
  相似文献   

19.
《Military psychology》2013,25(1):21-32
This research examined a model predicting soldier motivation. Line soldiers (N = 1,550) who had been members of personnel-stabilized battalions for at least 6 months responded to a questionnaire assessing perceptions of support received from peers and from leaders, identification with the work unit (company or battery), job-related self-esteem, personal adjustment, and performance motivation. Perceived leader support was a stronger predictor of performance motivation than was peer support, although both predictors demonstrated significant effects. In both cases, group-level mediation of the relationship between support and motivation was stronger than individual- level mediation. Findings indicate a need for increased emphasis on identi- fying leaders and training them in behaviors that will be seen as supportive of subordinates.  相似文献   

20.
BACKGROUND: Brain morphology and physiological measures in schizophrenia have yielded inconsistent results. This may be due in part to difficulties in ascertaining precisely to what degree each measure deviates from its genetically and environmentally determined potential level. We attempted to surmount this problem in a paradigm involving monozygotic twin pair discordant for schizophrenia. In this paradigm, the difference score and reaction time between the unaffected member and affected member of a twin pair should represent the degree of pathologic involvement irrespective of actual level. METHOD: We investigated, using fMRI, the neural substrate underlying encoding and retrieval of aversive and neutral IAPS pictures. RESULTS: An ANOVA on reaction time (RT) between schizophrenia patient (J) and normal sister (D) significant difference, (F = 5.2, p < or = .02) for J had less RT than D. Conversely, the ANOVA for the correct pictures retrieved was insignificant (F = 1.8, p < or = .2). When the brain activity associated with the encoding and retrieval of the aversive pictures was subtracted (J-D and D-J) from that associated with the neutral ones, significant loci of activation were found. During encoding: for J-D the right fusiform gyrus was significantly activated (p < .0001) and for D-J the orbitofrontal cortex was significantly activated (p < .05). During retrieval: for J-D the right anterior cingulate (p < .0001) was activated and the dorsolateral prefrontal cortex (p < .002). For D-J only the cerebellum showed activation (p < .0001). CONCLUSION: Results indicated subtle attenuations in some aspects of memory, thus providing another evidence for cognitive markers of a genetic component in schizophrenia. New approaches in neuropsychiatry-based on genetic methodologies should further define the cerebral physiology responsible for schizophrenia.  相似文献   

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