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991.
Stability or sensitivity analysis is an important topic in data analysis that has received little attention in the application of multidimensional scaling (MDS), for which the only available approaches are given in terms of a coordinate‐based analytical jackknife methodology. Although in MDS the prime interest is in assessing the stability of the points in the configuration, this methodology may be influenced by imprecisions resulting from the inherently necessary Procrustes method. This paper proposes an analytical distance‐based jackknife procedure to study stability and cross‐validation in MDS in terms of the jackknife distances, which is not influenced by the Procrustes method. For each object, the corresponding jackknife estimated points are considered as naturally clustered points, and stability and cross‐validation are analysed in terms of the MDS distances arising from the jackknife procedure, on the basis of a weighted cluster‐MDS algorithm. A jackknife‐relevant configuration is also proposed for cross‐validation in terms of coordinates, in a cluster‐MDS framework.  相似文献   
992.
Multidimensional computerized adaptive testing (MCAT) has received increasing attention over the past few years in educational measurement. Like all other formats of CAT, item replenishment is an essential part of MCAT for its item bank maintenance and management, which governs retiring overexposed or obsolete items over time and replacing them with new ones. Moreover, calibration precision of the new items will directly affect the estimation accuracy of examinees’ ability vectors. In unidimensional CAT (UCAT) and cognitive diagnostic CAT, online calibration techniques have been developed to effectively calibrate new items. However, there has been very little discussion of online calibration in MCAT in the literature. Thus, this paper proposes new online calibration methods for MCAT based upon some popular methods used in UCAT. Three representative methods, Method A, the ‘one EM cycle’ method and the ‘multiple EM cycles’ method, are generalized to MCAT. Three simulation studies were conducted to compare the three new methods by manipulating three factors (test length, item bank design, and level of correlation between coordinate dimensions). The results showed that all the new methods were able to recover the item parameters accurately, and the adaptive online calibration designs showed some improvements compared to the random design under most conditions.  相似文献   
993.
Subgroup analyses allow us to examine the influence of a categorical moderator on the effect size in meta‐analysis. We conducted a simulation study using a dichotomous moderator, and compared the impact of pooled versus separate estimates of the residual between‐studies variance on the statistical performance of the Q B (P) and Q B (S) tests for subgroup analyses assuming a mixed‐effects model. Our results suggested that similar performance can be expected as long as there are at least 20 studies and these are approximately balanced across categories. Conversely, when subgroups were unbalanced, the practical consequences of having heterogeneous residual between‐studies variances were more evident, with both tests leading to the wrong statistical conclusion more often than in the conditions with balanced subgroups. A pooled estimate should be preferred for most scenarios, unless the residual between‐studies variances are clearly different and there are enough studies in each category to obtain precise separate estimates.  相似文献   
994.
Examinee‐selected item (ESI) design, in which examinees are required to respond to a fixed number of items in a given set, always yields incomplete data (i.e., when only the selected items are answered, data are missing for the others) that are likely non‐ignorable in likelihood inference. Standard item response theory (IRT) models become infeasible when ESI data are missing not at random (MNAR). To solve this problem, the authors propose a two‐dimensional IRT model that posits one unidimensional IRT model for observed data and another for nominal selection patterns. The two latent variables are assumed to follow a bivariate normal distribution. In this study, the mirt freeware package was adopted to estimate parameters. The authors conduct an experiment to demonstrate that ESI data are often non‐ignorable and to determine how to apply the new model to the data collected. Two follow‐up simulation studies are conducted to assess the parameter recovery of the new model and the consequences for parameter estimation of ignoring MNAR data. The results of the two simulation studies indicate good parameter recovery of the new model and poor parameter recovery when non‐ignorable missing data were mistakenly treated as ignorable.  相似文献   
995.
Research has shown that children and adolescents with attentional control deficits tend to have high anxiety and exhibit threat‐related selective attentional bias. This study aimed to investigate how positive and negative attentional biases would interact with attentional control on dispositional anxiety. One hundred and twenty participants aged 18 years of age or younger participated in a visual dot‐probe task to measure their attentional bias and completed psychological questionnaires to measure their trait anxiety, and attentional control. Mean reaction times to the probe in milliseconds were used to measure attentional bias. Overall, our participants showed a bigger tendency towards attending to positive emotional stimuli than to negative emotional stimuli. Adolescents with high dispositional anxiety showed poorer attentional control. Regression analyses showed that attentional control interact with negative attentional bias to affect anxiety. For participants with high attentional control, higher negative attentional bias was associated with lower trait anxiety. Trait anxiety was not related to negative attentional bias for participants with low attentional control. Positive attentional bias showed no significant relationship with dispositional anxiety, either alone or in interaction with attentional control. Theoretical and clinical implications of the findings are also discussed.  相似文献   
996.
Sivin Kit 《Dialog》2017,56(3):260-271
How can Luther's contribution in theology and lessons arising from the Reformation have any relevance for Christians in Muslim‐majority Malaysia? In this article, I propose that a reflection on Luther's understanding of the so‐called “doctrine of two kingdoms”—better understood as God's two‐fold governance—offers a critical contribution that not only is relevant for the Malaysian Christian community, but also may have intercultural and interreligious implications for dialogue and engagement with the Muslim majority for interreligious solidarity and the common good.  相似文献   
997.
Children's emotion dysregulation and depressive symptoms are known to be affected by a range of individual (parent, child) and systemic (parent–child, marital, and family) characteristics. The current study builds on this literature by examining the unique role of coparental affect in children's emotion dysregulation, and whether this association mediates the link between parent and child depressive symptoms. Participants were 51 mother–father–child triads with children aged 7 to 12 (M age = 9.24 years). Triads discussed a time when the child felt sad and a time when the child felt happy. Maternal and paternal displays of positive affect were coded, and sequential analyses examined the extent to which parents were congruent in their displays of positive affect during the emotion discussions. Results indicated that interparental positive affect congruity (IPAC) during the sadness discussion, but not the happiness discussion, uniquely predicted parent‐reported child emotion dysregulation, above and beyond the contributions of child negative affect and parental punitive reactions. The degree of IPAC during the sadness discussion and child emotion dysregulation mediated the association between maternal, but not paternal, depressive symptoms and child depressive symptoms. Findings highlight the unique role of coparental affect in the socialization of sadness in youth and offer initial support for low levels of IPAC as a risk factor for the transmission of depressive symptoms in youth.  相似文献   
998.
This study presents the theoretical background, development, and psychometric properties of the German and English versions of the Experience in Personal Social Systems Questionnaire (EXIS.pers). It assesses how the members of a personal social system experience their situation within that system. It is designed as a research tool for interventions in which only one member of the system participates (e.g., Family Constellation Seminars). The EXIS.pers was created to measure change on the individual level relating to one's own important personal social system. In Study 1, we used exploratory factor analysis (EFA) for latent variable identification of the original German EXIS.pers (= 179). In Studies 2 and 3, we used confirmatory factor analysis (CFA) to examine the dimensionality of the German (= 634) and English (= 310) EXIS.pers. Internal consistencies and cross‐cultural structural equivalence were assessed. EFA indicated that a four‐factor model provided best fit for the German EXIS.pers. For both the German and English EXIS.pers, CFA provided the best fit for a five‐factor bi‐level model that included a general factor (Experience In Personal Social Systems) and four dimensions (Belonging, Autonomy, Accord, Confidence). Good internal consistencies, external associations, and cross‐cultural structural equivalence were demonstrated. This study provides first evidence for the German and English EXIS.pers as an economical and reliable measure of an individual's experience within his or her personal social systems.  相似文献   
999.
Very little is currently known about how increases in dispositional mindfulness through mindfulness training affect the quality of participants’ romantic relationships, and no previous studies have examined how increases in specific facets of mindfulness differentially contribute to relationship health. Additionally, even less is known about how an individual's development of mindfulness skills affects the relationship satisfaction of his or her romantic partner. Thus, the purpose of this pilot study was to examine associations between changes in facets of mindfulness and relationship satisfaction among participants enrolled in a Mindfulness‐Based Stress Reduction (MBSR) course and their nonenrolled romantic partners. Twenty MBSR participants and their nonenrolled partners (n = 40) completed measures of mindfulness and relationship satisfaction pre‐ and post‐enrolled partners’ completion of an MBSR course. Results indicated that enrolled participants significantly improved on all facets of mindfulness and relationship satisfaction, while nonenrolled partners did not significantly increase on any facet of mindfulness or relationship satisfaction. Moreover, enrolled participants’ increases in Acting with Awareness were positively associated with increases in their own and their nonenrolled partners’ relationship satisfaction, whereas increases in enrolled participants’ Nonreactivity were positively associated with increases in their nonenrolled partners’ (but not their own) relationship satisfaction. These results suggest that increasing levels of mindfulness (particularly specific aspects of mindfulness) may have positive effects on couples’ relationship satisfaction and highlight mindfulness training as a promising tool for education and intervention efforts aimed at promoting relational health.  相似文献   
1000.
Self‐determined learning is essential to academic success. The motivational resources development model argues that parents promote academic success in their children indirectly by nurturing self‐determined learner. In this study, applying a structural equation modelling and using data collected from 8th graders in Zhuhai, China (n = 1009) in 2012, we aim to answer 2 research questions: (a) What forms of parental involvement are highly correlated with self‐determined learning and (b) Can self‐determined learning fully mediate the relationship between parental involvement and students' academic performance? We find that parental leisure involvement is positively and significantly associated with the development of self‐determined learning, which in turn is significantly and positively correlated with academic achievement. Parental provision of structure or parental academic assistance is not significantly associated with students' self‐regulation and students' academic achievement.  相似文献   
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