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1.
《Structural equation modeling》2013,20(4):556-574
Approximations to the distributions of goodness-of-fit indexes in structural equation modeling are derived with the assumption of multivariate normality and slight misspecification of models. The fit indexes considered in this article are Joreskog and Sorbom's goodness-of-fit index (GFI) and the adjusted GFI, McDonald's absolute GFI, Steiger and Lind's root mean squared error of approximation, Steiger's Γ1 and Γ2, Bentler and Bonett's normed fit index, Bollen's incremental fit index and ρ1, Tucker and Lewis's index ρ2, and Bentler's fit index (McDonald and Marsh's relative noncentrality index). An approximation to the asymptotic covariance matrix for the fit indexes is derived by using the delta method. Furthermore, approximations to the densities of the fit indexes are obtained from the transformations of the asymptotically noncentral chi-square distributed variable. A simulation is carried out to confirm the accuracy of the approximations. 相似文献
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This investigation examined the effectiveness of reflection methods derived from Sternberg's theory of practical intelligence [Sternberg, R.J., and Hedlund, J. (2002). Practical intelligence, g, and work psychology. Human Performance 15(1/2), 143–160.; Sternberg, R.J., Forsythe, G.B., Hedlund, J., Horvath, H.A., Wagner, R.K., Williams, W.M., et al. (2000). Practical intelligence in everyday life. New York: Cambridge University Press. 2000] on the acquisition of experience-based, tacit knowledge. Two related experimental studies were conducted to test the effect of brief tacit-knowledge reflection training on practical problem solving. Reflection methods were developed based on Sternberg's conceptualized condition–action structure of tacit knowledge. In the first study, 101 U.S. Army officers participated in a reflection intervention or practice control. Results showed an effect of reflection condition on post-test tacit-knowledge scores (F [3, 91] = 3.74, p = .01, 2 = .03). In the second study, 235 college students participated in a reflection intervention or an academic-type reflection control. Results showed that the reflection condition approached significance on post-test scores (F [1, 233] = 3.47, p = .06, p = .06, 2 = .01). The investigation suggests this line of inquiry warrants continued study. 相似文献
4.
Parental involvement is well documented as a significant contributor to the self‐efficacy and academic achievement of students. A structural equation model of parent involvement with family socioeconomic status, student gender, parents’ aspirations for their children, mathematics efficacy, and mathematics achievement was tested to examine whether parent involvement in the 10th grade remains relevant to achievement. A sample of data pertaining to 8,673 10th graders from the Educational Longitudinal Study was analyzed. The results indicated that the fit of the measurement model to the data was good (χ2 = 3081.62, df = 87, p = .0, normed fit index [NFI] = .96, comparative fit index [CFI] = .96, root mean square error of approximation [RMSEA] = .064), as was the structural model (χ2 = 3470.69, df = 94, p = .00, NFI = .96, CFI = .96, RMSEA = .065). Although the effect was small in magnitude, parent involvement in advising had a significant indirect relationship with mathematics achievement via mathematics efficacy of 10th graders. 相似文献
5.
The dilaton in Weyl-Scale induced gravitational theory is regarded as a candidate of dark energy. When the potential of dilaton field is taken as the form Wσ ＋ σ^2e^-βσ2, that there exist attractor solutions to the canonical dilatonic dark energy model and the phontam model, and these attractors correspond to an equation of state ω = -1 and a cosmic density parameter Ωσ = 1, which are important features for a dark energy model and can fit with the current observations. We find a sufficient condition of the existence of a late time de Sitter attractor. The attractor behaviors, the evolutions of the state parameter ω and the cosmic density parameter Ω, the evolution of X （σ/σ0） and Y （σ/σ0^2） with respect to N（ln a）are shown numerically. 相似文献
6.
Haina H. Modi Megan M. Davis Wendy Troop Gordon Eva H. Telzer Karen D. Rudolph 《Child development》2023,94(2):529-543
To examine whether need for approval (NFA) and antisocial behavior (ASB) moderate the effects of socioemotional stimuli on cognitive control, 88 girls (Mage = 16.31 years; SD = 0.84; 65.9% White) completed a socioemotional Go/No-go and questionnaires. At high approach NFA, girls responded more slowly during appetitive than control (b = −8.80, p < .01) and aversive (b = −5.58, p = .01) trials. At high ASB, girls responded more slowly (b = −6.12, p = .02) and less accurately (OR = 1.11, p = .03) during appetitive than aversive trials; at low ASB, girls responded more slowly during aversive than control trials (b = −4.42, p = .04). Thus, both context and individual differences influence adolescents' cognitive control. 相似文献
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In the application of the Satorra–Bentler scaling correction, the choices of normal-theory weight matrices (i.e., the model-predicted vs. the sample covariance matrix) in the calculation of the correction remains unclear. Different software programs use different matrices by default. This simulation study investigates the discrepancies due to the weight matrices in the robust chi-square statistics, standard errors, and chi-square-based model fit indexes. This study varies the sample sizes at 100, 200, 500, and 1,000; kurtoses at 0, 7, and 21; and degrees of model misspecification, measured by the population root mean square error of approximation (RMSEA), at 0, .03, .05, .08, .10, and .15. The results favor the use of the model-predicted covariance matrix because it results in less false rejection rates under the correctly specified model, as well as more accurate standard errors across all conditions. For the sample-corrected robust RMSEA, comparative fit index (CFI) and Tucker–Lewis index (TLI), 2 matrices result in negligible differences. 相似文献
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Shi L Huang XQ Shi L Tao YF Yao YF Yu L Lin KQ Yi W Sun H Tokunaga K Chu JY 《Journal of Zhejiang University. Science. B》2011,12(6):428-435
A study of the human leukocyte antigen (HLA) genetic characteristics in the Zhuang, the largest ethnic population in China, would provide insight into Zhuang history and give a useful tool for disease associations, transplantation, and anthropology. In the present study, we report the comprehensive HLA-A, HLA-B, HLA-C, and HLA-DRB1 alleles and haplotypes in the Zhuang population of southern China for the first time. A total of 13 HLA-A, 24 HLA-B, 22 HLA-C, and 18 HLA-DRB1 were identified in 104 Zhuang individuals. The frequencies of HLA-A*11:01, A*02:07, A*24:02, A*02:03, and A*33:03 on A loci, B*15:02, B*58:01, B*46:01, and B*13:01 on B loci, C*03:04, C*08:01, C*01:02, C*03:02, and C*07:02 on C loci, and DRB1*15:01, DRB1*16:02, DRB1*14:01, DRB1*15:02, and DRB1*03:01 on the DRB1 loci were >10%. The A*33:03-C*03:02-B*58:01-DRB1*03:01 and A*02:07-C*01:02-B*46:01-DRB1*14:01 haplotypes were predominant in the Zhuang. The phylogenetic tree, as well as the analysis of haplotypes, suggested that the Zhuang are genetically similar to southern Chinese populations, especially the Zhuang-Dong language-speaking populations, such as the Bouyei, Dai, and Maonan. Even though the Zhuang and southern Chinese populations shared common alleles and haplotypes, the Zhuang has maintained its unique genetic characteristics. 相似文献
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We highlight critical conceptual and statistical issues and how to resolve them in conducting Satorra–Bentler (SB) scaled difference chi-square tests. Concerning the original (Satorra & Bentler, 2001) and new (Satorra & Bentler, 2010) scaled difference tests, a fundamental difference exists in how to compute properly a model's scaling correction factor (c), depending on the particular structural equation modeling software used. Because of how LISREL 8 defines the SB scaled chi-square, LISREL users should compute c for each model by dividing the model's normal theory weighted least-squares (NTWLS) chi-square by its SB chi-square, to recover c accurately with both tests. EQS and Mplus users, in contrast, should divide the model's maximum likelihood (ML) chi-square by its SB chi-square to recover c. Because ML estimation does not minimize the NTWLS chi-square, however, it can produce a negative difference in nested NTWLS chi-square values. Thus, we recommend the standard practice of testing the scaled difference in ML chi-square values for models M 1 and M 0 (after properly recovering c for each model), to avoid an inadmissible test numerator. We illustrate the difference in computations across software programs for the original and new scaled tests and provide LISREL, EQS, and Mplus syntax in both single- and multiple-group form for specifying the model M 10 that is involved in the new test. 相似文献
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The F-distribution approximation suggested by Dixon was investigated at various combinations of alpha and degrees of freedom. Tabled values were compared with values computed utilizing the suggested formula. The results indicate that while the formula is not useful in all cases, the adequacy of the approximation generally increases as alpha, v1, and v2 increase. It is suggested that the approximation may be utilized when certain restrictions regarding alpha, v1, and v2 are met. 相似文献
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Alberto Maydeu-Olivares Amanda J. Fairchild Alexander G. Hall 《Structural equation modeling》2017,24(4):495-505
The power of the chi-square test statistic used in structural equation modeling decreases as the absolute value of excess kurtosis of the observed data increases. Excess kurtosis is more likely the smaller the number of item response categories. As a result, fit is likely to improve as the number of item response categories decreases, regardless of the true underlying factor structure or χ2-based fit index used to examine model fit. Equivalently, given a target value of approximate fit (e.g., root mean square error of approximation ≤ .05) a model with more factors is needed to reach it as the number of categories increases. This is true regardless of whether the data are treated as continuous (common factor analysis) or as discrete (ordinal factor analysis). We recommend using a large number of response alternatives (≥ 5) to increase the power to detect incorrect substantive models. 相似文献
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Fit indexes are an important tool in the evaluation of model fit in structural equation modeling (SEM). Currently, the newest confidence interval (CI) for fit indexes proposed by Zhang and Savalei (2016) is based on the quantiles of a bootstrap sampling distribution at a single level of misspecification. This method, despite a great improvement over naive and model-based bootstrap methods, still suffers from unsatisfactory coverage. In this work, we propose a new method of constructing bootstrap CIs for various fit indexes. This method directly inverts a bootstrap test and produces a CI that involves levels of misspecification that would not be rejected in a bootstrap test. Similar in rationale to a parametric CI of root mean square error of approximation (RMSEA) based on a noncentral χ2 distribution and a profile-likelihood CI of model parameters, this approach is shown to have better performance than the approach of Zhang and Savalei (2016), with more accurate coverage and more efficient widths. 相似文献
13.
《Structural equation modeling》2013,20(3):305-319
This article considers the implications for other noncentrality parameter-based statistics from Steiger's (1998) multiple sample adjustment to the root mean square error of approximation (RMSEA) measure. When a structural equation model is fitted simultaneously in more than 1 sample, it is shown that the calculation of the noncentrality parameter used in tests of approximate fit and in point and interval estimators of other noncentral fit statistics (except the expected cross-validation index) also requires a likeminded adjustment. Furthermore, it is shown that an adjustment is needed in multiple sample models for correctly calculating MacCallum, Browne, and Sugawara's (1996) approach to power analysis. The accuracy of these proposals is investigated and demonstrated in a small Monte Carlo study in which particular attention is paid to using appropriately constructed covariance matrices that give specified nonzero population discrepancy values under maximum likelihood estimation. 相似文献
14.
Morten Moshagen 《Structural equation modeling》2013,20(1):86-98
The size of a model has been shown to critically affect the goodness of approximation of the model fit statistic T to the asymptotic chi-square distribution in finite samples. It is not clear, however, whether this “model size effect” is a function of the number of manifest variables, the number of free parameters, or both. It is demonstrated by means of 2 Monte Carlo computer simulation studies that neither the number of free parameters to be estimated nor the model degrees of freedom systematically affect the T statistic when the number of manifest variables is held constant. Increasing the number of manifest variables, however, is associated with a severe bias. These results imply that model fit drastically depends on the size of the covariance matrix and that future studies involving goodness-of-fit statistics should always consider the number of manifest variables, but can safely neglect the influence of particular model specifications. 相似文献
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Allan B. de Guzman Charmaine Lei M. Lacson Abegail I. Labbao 《Educational gerontology》2015,41(6):399-416
While morale among the elderly has been widely and extensively studied, results are varied and at times conflicting. Hence, the purpose of this study is to explore the factors affecting elderly morale of a select group of Filipinos in a community setting. A 64-item questionnaire was utilized to survey 323 Filipinos aged 60 and above residing in the National Capital Region of the Philippines in May 2013. Respondents completed a robotfoto, a checklist of chronic illnesses, and measures of the social support, functional ability, geriatric depression, and morale. Structural equation modeling was used to test the hypothesized model. Two competing models emerged in the study. Model 1 followed causal relationships indicated in the hypothesized model while model 2 considered modification indices that surfaced more acceptable fit indices (X2/df = 1.414, GFI [goodness of fit index] = 0.988, CFI [comparative fit index] = 0.987, RMSEA [root mean square error of approximation] = 0.036). Chronic illness, social support, and depression were found to be major predictors of morale. Number of chronic illnesses and depression were also found to have a negative relationship with functional ability, and chronic illness and social support were negatively correlated. Findings can assist health professionals such as nurses to identify the factors that shape elderly morale vis-a-vis the use of effective strategies that promote the well-being of elderly people. The emerging model can serve as reference to assess the effectiveness of quality of care rendered as manifested by morale. 相似文献
16.
Emotion regulation (ER) is an integral aspect of emerging adults’ mental health, yet little is known about interpersonal factors that influence ER in during this period. This investigation examines emerging adults’ desire to emulate parental ER skills in the relation between perceived parental ER and emerging adults’ emotion dysregulation.A sample of 79 emerging adults (Mage = 18.55 years, SD = .32; 88.6% female, 69.6% White) completed measures of perceived parental ER (Affective Style Questionnaire [ASQ]Hofmann and Kashdan 2010), emotion dysregulation (Difficulties in Emotion Regulation Scale [DERS]Gratz and Roemer 2004), and desire to emulate parental ER (Perception of Emotion Regulation Scale [PERS]).A desire to emulate parental ER skills moderated the relationship between perceived parental ER and emerging adults’ emotion dysregulation in general (B = -.10, SE = .048, t = ?2.07, p = .043), and low emotional awareness in particular (B = -.04 SE = .02, t = ?2.47, p = .02).Findings suggest that emerging adults with an increased desire to emulate parents with lower ER skills report greater emotion dysregulation. Implications for clinical practice, along with future directions for the field of ER, are discussed. 相似文献
17.
Bruce Thompson 《Journal of Experimental Education》2013,81(1):80-93
The author asserts that editors should publicly declare their expectations and expose the rationales for editorial policies to public scrutiny. He argues that editorial policies ought to require effect size reporting, as those at 17 journals now do. He also argues (a) that score reliabilities should be reported; (b) that stepwise methods should not be used; (c) that structure coefficients should be interpreted; and (d) that if used wisely, confidence intervals differ from hypothesis tests in important ways. The use of noncentral t and F distributions to create confidence intervals about effect sizes also is appealing. 相似文献
18.
This paper discusses stress intensity factor (SIF) calculations for surface cracks in round bars subjected to combined torsion
and bending loadings. Different crack aspect ratios, a/b, ranging from 0.0 to 1.2 and relative crack depths, a/D, ranging from 0.1 to 0.6 were considered. Since the loading was non-symmetrical for torsion loadings, a whole finite element
model was constructed. Then, the individual and combined bending and torsion loadings were remotely applied to the model.
The equivalent SIF method, F*EQ, was then used explicitly to combine the individual SIFs from the bending and torsion loadings. A comparison was then carried
out with the combined SIF, F*FE, obtained using the finite element analysis (FEA) under similar loadings. It was found that the equivalent SIF method successfully
predicted the combined SIF for Mode I. However, discrepancies between the results determined from the different approaches
occurred when F
III was involved. It was also noted that the predicted F*FE using FEA was higher than the F*EQ predicted through the equivalent SIF method due to the difference in crack face interactions. 相似文献
19.
A rice mutant with Yaponica 9522 cultivar background Oryza sativa extraordinary glume 1 （Oseg 1） was identified from the M2 mutant pool mutagenized by ^60Co γ-ray. Compared with wild type plants, Oseg 1 developed longer empty glumes and rudimentary glumes. In some Oseg 1 mutants, the number of stamens of flowers was reduced and leaf-like lodicules occurred, and excessive lemma/palea-like organ could be observed in some mutant spikelets. This indicated that OsEG1 could regulate the development of rudimentary glumes, empty glumes, lemma/palea, lodicules, and stamens. Genetic analysis indicated that Oseg 1 came from a single recessive genetic locus. To clone OsEG1 gene, F2 population was constructed by a cross between Oseg 1 （Japonica） and Guangluai4 （Indica）. Using map-based cloning approach, OsEG1 was mapped on chromosome 4, between INDEL marker OS407 and WHM0466 with genetic distance of 2.0 cm and 1.0 cm, respectively. These results are useful for further cloning and functional analysis of the OsEG1 gene. 相似文献
20.
Zhang Hanlin 《上海大学学报(英文版)》1998,2(3):191-193
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