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231.
    
Psychologists are interested in whether friends and couples share similar personalities or not. However, no statistical models are readily available to test the association between personalities and social relations in the literature. In this study, we develop a statistical model for analyzing social network data with the latent personality traits as covariates. Because the model contains a measurement model for the latent traits and a structural model for the relationship between the network and latent traits, we discuss it under the general framework of structural equation modeling (SEM). In our model, the structural relation between the latent variable(s) and the outcome variable is no longer linear or generalized linear. To obtain model parameter estimates, we propose to use a two-stage maximum likelihood (ML) procedure. This modeling framework is evaluated through a simulation study under representative conditions that would be found in social network data. Its usefulness is then demonstrated through an empirical application to a college friendship network.  相似文献   
232.
    
High-pressure structural stability studies have been carried out on tungsten boride W2B5 up to maximum pressure of 36 GPa using a Mao-Bell diamond-anvil cell at beamline BR-12 of the ELETTRA synchrotron facility (λ = 0.68881 Å). The hexagonal phase (S.G:P63/mmc) of W2B5 is stable up to the maximum pressure studied. The bulk modulus is estimated to be ~347 GPa using the Birch–Murnaghan equation of state. The variation of lattice parameters and bond lengths B–B and W–B have been studied and the c-axis is seen to be marginally more compressible than the a-axis.  相似文献   
233.
A Pd81Si19 bulk metallic glassy rod with a diameter of 4.5 mm was produced by water quenching the fluxed alloy. Despite a negative heat of mixing between Pd and Si elements and very simple components constituting the binary Pd–Si glass-forming system, structural heterogeneity was induced either by slow cooling of a liquid or sub-Tg annealing of glassy ribbons. The sub-Tg annealing experiments evidenced that a more ordered amorphous phase emerged from the original glassy matrix. Our work provides an alternative way to tune the microstructure of metallic glasses by subsequent thermal treatment on an as-prepared single glassy phase.  相似文献   
234.
    
Cluster bias refers to measurement bias with respect to the clustering variable in multilevel data. The absence of cluster bias implies absence of bias with respect to any cluster‐level (level 2) variable. The variables that possibly cause the bias do not have to be measured to test for cluster bias. Therefore, the test for cluster bias serves as a global test of measurement bias with respect to any level 2 variable. However, the validity of the global test depends on the Type I and Type II error rates of the test. We compare the performance of the test for cluster bias with the restricted factor analysis (RFA) test, which can be used if the variable that leads to measurement bias is measured. It appeared that the RFA test has considerably more power than the test for cluster bias. However, the false positive rates of the test for cluster bias were generally around the expected values, while the RFA test showed unacceptably high false positive rates in some conditions. We conclude that if no significant cluster bias is found, still significant bias with respect to a level 2 violator can be detected with an RFA model. Although the test for cluster bias is less powerful, an advantage of the test is that the cause of the bias does not need to be measured, or even known.  相似文献   
235.
    
All Lives Matter (ALM) has emerged as a response to, and critique of, the Black Lives Matter (BLM) anti-racist movement. ALM has been shown to work to undermine and attempt to deracialise BLM; however, there is a need for a comprehensive understanding of how ALM functions in online interactions. The research questions are therefore: What different ways is ALM used in Twitter debates?, How prevalent are these different uses?, and What function do the different uses of ALM perform in the wider debate around BLM? To address these questions, we employed a mixed-method approach drawing on topic modelling and critical discursive psychology of Twitter posts using the hashtag #AllLivesMatter. A corpus of 294,217 unique tweets sent by 145,994 unique users was subject to Structural Topic Modelling (STM), which resulted in 60 topics, and from this, a sub-dataset of 180 tweets was generated for discourse analysis. The STM identified 12 distinct uses of ALM, ranging from direct and even extreme opposition to BLM to criticisms of ALM and support of BLM and anti-racism messages, both of which are explored in the discourse analysis. Together, the analysis suggests that, at least on Twitter, the ALM hashtag is not one-dimensional nor a settled debate. Moreover, the Twitter public can use the ALM hashtag to denounce racism and the ideological pretext of ALM.  相似文献   
236.
    
The personal development of students is an essential component of school guidance and counselling programmes, but no published research on guidance and counselling has investigated the effects of regular classroom teaching on students' self-efficacy for personal development. In this study, questionnaire items were constructed to measure classroom teaching, student self-efficacy for personal development and student use of deep learning strategies. Data were collected from 16,208 secondary school students in Hong Kong. Using structural equation modelling, regular classroom teaching was found to have a direct effect on personal development self-efficacy as well as an indirect effect through student use of deep learning strategies. Implications of these findings for implementing a whole-school approach to guidance and counselling are discussed.  相似文献   
237.
  总被引:1,自引:0,他引:1  
The present study reports results from a study of the self-reported fears of identical twins and their spouses and offspring. Factor analysis with oblique rotation of questionnaire responses yielded four correlated fear dimensions: situational fears, illness-injury fears, social fears, and fear of small animals. Models allowing for genetic and cultural transmission, together with specially correlated environments for twins, were fitted, both for separate fears and across fears. Simple models with only genetic and uncorrelated environments were sufficient to account for each the fear dimensions considered separately. The cross-dimensional analyses revealed a genetic and an environmental factor common to the four fear dimensions, together with fear-specific genetic and environmental factors. The impact of the common genetic and common environmental factor varied across dimensions. No evidence of cultural transmission or specially correlated twin environments of the cross-dimensional environments was detected. It is concluded that both common and fear-specific genes and (individual-specific) common and fear-specific environments are necessary to account for the data. The results are discussed in terms of the prepared learning hypothesis and the expectancy bias hypothesis.  相似文献   
238.
    
The aim of the present study was to test two structural models of the relationship between appraised psychological workload and musculoskeletal symptoms from the neck, shoulder, and upper and lower back with different aspects of perceived fatigue as mediating variables. In this cross-sectional study a questionnaire survey was conducted among employees at three Swedish assembly plants (n= 305). The proposed models were tested for one general fatigue dimension--lack of energy--and four specific fatigue dimensions--physical discomfort, physical exertion, lack of motivation, and sleepiness--using structural equation modeling. The results indicate that the role of perceived fatigue in the relationship between appraised workload and musculoskeletal symptoms is different for different aspects of fatigue. The general fatigue dimension, lack of energy, does not mediate the relationship. As regards the specific fatigue dimensions, the relationship is partially mediated by physical discomfort and lack of motivation but not by physical exertion or sleepiness. Appraised psychological workload has a unique effect on musculoskeletal symptoms not mediated by fatigue.  相似文献   
239.
    
Past research has demonstrated clearly the importance of pre‐purchase information search within the buying process. Scholars have identified several sources used by consumers in order to obtain information relevant to their purchase situation. Among the various information sources, interpersonal non‐commercial sources seem to play an important role in consumers' choice decisions. The present study examines potential antecedents of consumer relative preference for interpersonal information search. The proposed antecedents include personality traits such as individuals' susceptibility to interpersonal influence, their need for cognition and their self‐confidence, as well as individual differences in product knowledge and perceived risk associated with the purchase of a specific product. Using structural equation modelling on survey data (419 respondents), seven hypotheses — describing relationships between the diverse variables of the model — were tested. The results indicate that consumer relative preference for interpersonal information search was significantly influenced by consumers' susceptibility to interpersonal influence, their need for cognition, their self‐confidence and their product knowledge. Consumers' product knowledge also influenced their perceived risk, which did not affect their preference for interpersonal search significantly. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
240.
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