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Extended redundancy analysis (ERA) is used to reduce multiple sets of predictors to a smaller number of components and examine the effects of these components on a response variable. In various social and behavioural studies, auxiliary covariates (e.g., gender, ethnicity) can often lead to heterogeneous subgroups of observations, each of which involves distinctive relationships between predictor and response variables. ERA is currently unable to consider such covariate-dependent heterogeneity to examine whether the model parameters vary across subgroups differentiated by covariates. To address this issue, we combine ERA with model-based recursive partitioning in a single framework. This combined method, MOB-ERA, aims to partition observations into heterogeneous subgroups recursively based on a set of covariates while fitting a specified ERA model to data. Upon the completion of the partitioning procedure, one can easily examine the difference in the estimated ERA parameters across covariate-dependent subgroups. Moreover, it produces a tree diagram that aids in visualizing a hierarchy of partitioning covariates, as well as interpreting their interactions. In the analysis of public data concerning nicotine dependence among US adults, the method uncovered heterogeneous subgroups characterized by several sociodemographic covariates, each of which yielded different directional relationships between three predictor sets and nicotine dependence.  相似文献   
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This paper reports on a series of experiments designed to assess the impact of grouping decision makers by level of cognitive complexity on the outcomes they attain in crisis negotiations. The participants—University of Maryland undergraduates who took roles in a simulated international hostage crisis—used a computer decision support system and a controlled network environment for communications. The goal of the experiments was to better understand the dynamics that lead certain types of groupings to have greater success in negotiations, and that lead certain groups of adversaries to achieve more mutually beneficial outcomes such as compromise and agreement. The findings point to a positive relationship between the level of homogeneity in cognitive complexity among decision makers and the achievement of positive outcomes in crisis negotiations.  相似文献   
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Recent research has questioned the validity of identifying depression and anxiety as separate constructs in children. The current investigation examined the usefulness of the Positive and Negative Affect Schedule for Children (PANAS-C) in differentiating between anxiety and depression in children while also providing needed reliability and validity data on the PANAS-C. In addition, the relationship between positive and negative affect and coping was examined. Subjects included 110 third through fifth graders from a semirural public school setting. Children completed the PANAS-C, as well as self-report measures of depression, anxiety, and coping strategies. Moderate item–total correlations and high internal consistency indicated that the PANAS-C has good reliability. Validity results were mixed: a two-factor solution resembled previous studies, and negative affect was associated with avoidance coping strategies whereas positive affect was associated with approach coping strategies, as expected. However, correlations of positive and negative affect, anxiety, and depression scales suggest that positive and negative affectivity are negatively related in children as opposed to separate and independent constructs. Results of the present investigation question the validity of the use of the PANAS-C for differentiating anxiety and depression with this age group and lend support to the possibility that high overlap between anxiety and depression in this age group may be specific for childhood depression.  相似文献   
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