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241.
A weighted Euclidean distance model for analyzing three-way dissimilarity data (stimuli by stimuli by subjects) for heterogeneous subjects is proposed. First, it is shown that INDSCAL may fail to identify a common space representative of the observed data structure in presence of heterogeneity. A new model that removes the rotational invariance of the classical multidimensional scaling problem and specifies K common homogeneous spaces is proposed. The model, called mixture INDSCAL in K classes, or briefly K-INDSCAL, still includes individual saliencies. However, the large number of parameters in K-INDSCAL may produce instability of the estimates and therefore a parsimonious model will also be discussed. The parameters of the model are estimated in a least-squares fitting context and an efficient coordinate descent algorithm is given. The usefulness of K-INDSCAL is demonstrated by both artificial and real data analyses.  相似文献   
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Cohen’s Linearly Weighted Kappa is a Weighted Average of 2×2 Kappas   总被引:1,自引:0,他引:1  
An agreement table with n∈ℕ≥3 ordered categories can be collapsed into n−1 distinct 2×2 tables by combining adjacent categories. Vanbelle and Albert (Stat. Methodol. 6:157–163, 2009c) showed that the components of Cohen’s weighted kappa with linear weights can be obtained from these n−1 collapsed 2×2 tables. In this paper we consider several consequences of this result. One is that the weighted kappa with linear weights can be interpreted as a weighted arithmetic mean of the kappas corresponding to the 2×2 tables, where the weights are the denominators of the 2×2 kappas. In addition, it is shown that similar results and interpretations hold for linearly weighted kappas for multiple raters.  相似文献   
244.
When the factor analysis model holds, component loadings are linear combinations of factor loadings, and vice versa. This interrelation permits us to define new optimization criteria and estimation methods for exploratory factor analysis. Although this article is primarily conceptual in nature, an illustrative example and a small simulation show the methodology to be promising.  相似文献   
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Structural equation models are increasingly used as a modeling tool for multivariate time series data in the social and behavioral sciences. Standard error estimators of SEM models, originally developed for independent data, require modifications to accommodate the fact that time series data are inherently dependent. In this article, we extend a sandwich-type standard error estimator of independent data to multivariate time series data. One required element of this estimator is the asymptotic covariance matrix of concurrent and lagged correlations among manifest variables, whose closed-form expression has not been presented in the literature. The performance of the adapted sandwich-type standard error estimator is evaluated using a simulation study and further illustrated using an empirical example.  相似文献   
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We examined associations between spiritual well-being and CAM use among 4,139 cancer survivors. We also explored the classification of religious/spiritual practices (R/S) as CAMs and alternative subscale structures of the Functional Assessment of Chronic Illness Therapy—Spiritual Well-being (FACIT-Sp). We evaluated three aspects of spirituality, Faith, Peace, and Meaning, and use of 19 CAMs in 5 domains. Mind–body methods were subdivided into R/S and non-R/S. All FACIT-Sp factors were associated with CAM use, but in different directions: Meaning and Faith were positively associated; Peace was negatively associated. Peace was negatively associated with R/S CAMs, but not non-R/S CAMs. The prevalence of CAM use dropped from 79.3 to 64.8% when R/S items were excluded. These findings confirm an association between spiritual well-being and CAM use, including some non-R/S CAMs, and provide evidence of the benefits of using the three-factor FACIT-Sp solution and treating R/S CAMs as a separate category.  相似文献   
249.
A growing body of research suggests that religion may exert a beneficial effect on both physical and mental health. Unfortunately, the rapid growth of this literature has made it difficult to get a clear picture of what has been accomplished. This issue is addressed by presenting a conceptual model that focuses on the needs that are satisfied by religion. In the process, an effort is made to show how this conceptual scheme can be used to add greater coherence to the field.  相似文献   
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