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261.
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
262.
Jimmy de la Torre 《Psychometrika》2011,76(3):510-510
263.
Matthijs J. Warrens 《Psychometrika》2011,76(3):471-486
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
264.
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
265.
266.
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
267.
268.
This paper first discusses the relationship between Kullback–Leibler information (KL) and Fisher information in the context
of multi-dimensional item response theory and is further interpreted for the two-dimensional case, from a geometric perspective.
This explication should allow for a better understanding of the various item selection methods in multi-dimensional adaptive
tests (MAT) which are based on these two information measures. The KL information index (KI) method is then discussed and
two theorems are derived to quantify the relationship between KI and item parameters. Due to the fact that most of the existing
item selection algorithms for MAT bear severe computational complexity, which substantially lowers the applicability of MAT,
two versions of simplified KL index (SKI), built from the analytical results, are proposed to mimic the behavior of KI, while
reducing the overall computational intensity. 相似文献
269.
Previous research investigating attentional bias has produced intriguingly equivocal results. The present large-scale study
explored attentional bias in subjects diagnosed with obsessive-compulsive disorder (OCD) and in a control group (n = 80) using the Emotional Stroop Test. Results clearly indicated poorer performances across the board amongst patients diagnosed
with OCD compared to the control group, particularly in the case of anxiety-related stimuli. This paper discusses, in the
light of current models of attentional bias towards threat in anxiety disorders, the processes whereby attentional bias towards
anxiety stimuli might play a vital role in the causation and maintenance of OCD. 相似文献
270.
Margaret P. Wardlaw 《Journal of religion and health》2011,50(1):62-74
Modern medicine serves a religious function for modern Americans as a conduit through which science can be applied directly
to the human body. The first half of this paper will focus on the theoretical foundations for viewing medicine as a religious
practice arguing that just as a hierarchical structured authoritarian church historically mediated access to God, contemporary
Western medicine provides a conduit by which the universalizable truths of science can be applied to the human being thereby
functioning as a new established religion. I will then illustrate the many parallels between medicine and religion through
an analysis of rituals and symbols surrounding and embedded within the modern practice of medicine. This analysis will pay
special attention to the primacy placed on secret interior knowledge of the human body. I will end by responding to the hope
for a “secularization of American medicine,” exploring some of the negative consequences of secularization, and arguing that,
rather than seeking to secularize, American medicine should strive to use its religious features to offer hope and healing
to the sick, in keeping with its historically religious legacy. 相似文献