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1.
A latent variable modeling procedure for examining whether a studied population could be a mixture of 2 or more latent classes is discussed. The approach can be used to evaluate a single-class model vis-à-vis competing models of increasing complexity for a given set of observed variables without making any assumptions about their within-class interrelationships. The method is helpful in the initial stages of finite mixture analyses to assess whether models with 2 or more classes should be subsequently considered as opposed to a single-class model. The discussed procedure is illustrated with a numerical example. 相似文献
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We consider a multivariate generalized latent variable model to investigate the effects of observable and latent explanatory variables on multiple responses of interest. Various types of correlated responses, such as continuous, count, ordinal, and nominal variables, are considered in the regression. A generalized confirmatory factor analysis model that is capable of managing mixed-type data is proposed to characterize latent variables via correlated observed indicators. In addressing the complicated structure of the proposed model, we introduce continuous underlying measurements to provide a unified model framework for mixed-type data. We develop a multivariate version of the Bayesian adaptive least absolute shrinkage and selection operator procedure, which is implemented with a Markov chain Monte Carlo (MCMC) algorithm in a full Bayesian context, to simultaneously conduct estimation and model selection. The empirical performance of the proposed methodology is demonstrated through a simulation study. An application of the proposed method to a study of adolescent substance abuse based on the National Longitudinal Survey of Youth is presented. 相似文献
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Most researchers acknowledge that virtually all structural equation models (SEMs) are approximations due to violating distributional assumptions and structural misspecifications. There is a large literature on the unmet distributional assumptions, but much less on structural misspecifications. In this paper, we examine the robustness to structural misspecification of the model implied instrumental variable, two-stage least square (MIIV-2SLS) estimator of SEMs. We introduce two types of robustness: robust-unchanged and robust-consistent. We develop new robustness analytic conditions for MIIV-2SLS and illustrate these with hypothetical models, simulated data, and an empirical example. Our conditions enable a researcher to know whether, for example, a structural misspecification in the latent variable model influences the MIIV-2SLS estimator for measurement model equations and vice versa. Similarly, we establish robustness conditions for correlated errors. The new robustness conditions provide guidance on the types of structural misspecifications that affect parameter estimates and they assist in diagnosing the source of detected problems with MIIVs. 相似文献
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Larry R. Price Daniel P. Gonzalez Tiffany A. Whittaker 《Structural equation modeling》2019,26(1):12-23
A problem central to structural equation modeling is measurement model specification error and its propagation into the structural part of nonrecursive latent variable models. Full-information estimation techniques such as maximum likelihood are consistent when the model is correctly specified and the sample size large enough; however, any misspecification within the model can affect parameter estimates in other parts of the model. The goals of this study included comparing the bias, efficiency, and accuracy of hypothesis tests in nonrecursive latent variable models with indirect and direct feedback loops. We compare the performance of maximum likelihood, two-stage least-squares and Bayesian estimators in nonrecursive latent variable models with indirect and direct feedback loops under various degrees of misspecification in small to moderate sample size conditions. 相似文献
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Barbara R. Foorman Yaacov Petscher Christopher Stanley Adrea Truckenmiller 《Journal of research on educational effectiveness》2017,10(3):619-645
The objective of this study was to determine the latent profiles of reading and language skills that characterized 7,752 students in kindergarten through tenth grade and to relate the profiles to norm-referenced reading outcomes. Reading and language skills were assessed with a computer-adaptive assessment administered in the middle of the year and reading outcome measures were administered at the end of the year. Three measures of reading comprehension were administered in third through tenth grades to create a latent variable. Latent profile analysis (LPA) was conducted on the reading and language measures and related to reading outcomes in multiple regression analyses. Within-grade multiple regressions were subjected to a linear step-up correction to guard against false-discovery rate. LPA results revealed five to six profiles in the elementary grades and three in the secondary grades that were strongly related to standardized reading outcomes, with average absolute between-profile effect sizes ranging from 1.10 to 2.53. The profiles in the secondary grades followed a high, medium, and low pattern. Profiles in the elementary grades revealed more heterogeneity, suggestive of strategies for differentiating instruction. 相似文献
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Divergent Thinking is a domain-general mental attribute closely associated with creativity that can be quantified through the use of text-mining algorithms. Past research has shown that students’ Divergent Thinking is malleable in response to relatively simple contextual prompts. In addition, there is substantial variance in the degree to which individual students’ Divergent Thinking is malleable, suggesting the presence of a student-specific zone-of-proximal-development in relation to creativity. Here, we adopted a dynamic assessment paradigm that included multiple conditions under which student Divergent Thinking was measured and fit a latent profile analysis model to that dynamic assessment data. We found that, although on average the Originality of student responses can be augmented through a prompt to generate surprising or unusual ideas, three latent classes emerged that differed significantly on their patterns of augmentation. These three latent classes were termed: (a) Conventional Thinkers (7.80% of the sample), whose response to the Divergent Thinking task were highly constrained and unoriginal across all conditions (b) Prompted Shifters (66.56%), whose Originality significantly increased across conditions, and (c) Idea Generators (25.64%), whose responses were highly original across all conditions. These latent profiles were validated in regard to personality characteristics and domain-specific creative activities, with Idea Generators reporting significantly more Openness and Intellect, less Industriousness, and more creative activities across the domains of Literature, Music, Sports, Visual Art, Science, and Cooking than did the other latent classes. 相似文献
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Although much is known about the performance of recent methods for inference and interval estimation for indirect or mediated effects with observed variables, little is known about their performance in latent variable models. This article presents an extensive Monte Carlo study of 11 different leading or popular methods adapted to structural equation models with latent variables. Manipulated variables included sample size, number of indicators per latent variable, internal consistency per set of indicators, and 16 different path combinations between latent variables. Results indicate that some popular or previously recommended methods, such as the bias-corrected bootstrap and asymptotic standard errors had poorly calibrated Type I error and coverage rates in some conditions. Likelihood-based confidence intervals, the distribution of the product method, and the percentile bootstrap emerged as leading methods for both interval estimation and inference, whereas joint significance tests and the partial posterior method performed well for inference. 相似文献
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Allison J. Tracy Sumru Erkut Michelle V. Porche Jo Kim Linda Charmaraman Jennifer M. Grossman 《Structural equation modeling》2013,20(1):110-133
In this article, we operationalize identification of mixed racial and ethnic ancestry among adolescents as a latent variable to (a) account for measurement uncertainty, and (b) compare alternative wording formats for racial and ethnic self-categorization in surveys. Two latent variable models were fit to multiple mixed-ancestry indicator data from 1,738 adolescents in New England. The first, a mixture factor model, accounts for the zero-inflated mixture distribution underlying mixed-ancestry identification. Alternatively, a latent class model allows classification distinction between relatively ambiguous versus unambiguous mixed-ancestry responses. Comparison of individual indicators reveals that the Census 2000 survey version estimates higher prevalence of mixed ancestry but is less sensitive to relative certainty of identification than are alternate survey versions (i.e., offering a “mixed” check box option, allowing a written response). Ease of coding and missing data are also considered in discussing the relative merit of individual mixed-ancestry indicators among adolescents. 相似文献
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Nancy Boudreau James Sullivan William Balzer Ann Marie Ryan Robert Yonker Todd Thorsteinson Peter Hutchinson 《Research in higher education》1997,38(3):297-312
Many different approaches, almost all of which use some form of regression, have been used to study the issue of gender equity in university faculty salaries. One major point of contention in ail of these approaches is whether faculty rank, which is university conferred, should be included as a predictor variable. Two illustrations are presented to demonstrate how omitting faculty rank as a predictor variable from gender equity studies of university faculty salaries can lead to incorrect conclusions concerning gender discrimination. The first illustration uses hypothetical data constructed so that there is no difference in salary due to gender. However, when faculty rank is not included as a predictor variable in the regression model, there is a significant difference in salary due to gender. The second illustration uses actual data from a study of gender equity in pay at Bowling Green State University. This data set is used to construct a new data set that is totally free of gender bias. When a regression model omitting faculty rank is fit to this gender bias-free data, again a significant difference in salary due to gender is present. Therefore, it is recommended that faculty rank be included as a predictor variable in any model used to study gender equity relating to salary. 相似文献
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The control-of-variables strategy (CVS) is considered a hallmark in the development of scientific reasoning. It holds that informative experiments need to be contrastive and controlled. Prior evidence suggests that CVS is connected to the acquisition of science content knowledge. In a cross-sectional study involving 1283 high school students (grades 5–13), we investigate whether students’ mastery of CVS is related to their science content knowledge in physics. A latent variable model indicates that CVS is substantially associated with students’ science content knowledge, even when controlling for common effects of general reasoning abilities. Substantial differences in students’ CVS skills and their science content knowledge exist between the lower grade levels in secondary school when students receive physics education. A latent profile analysis shows that the most difficult aspect of CVS is understanding the impact of confounding. This sub-skill emerges in late secondary school and it requires that students master more procedural sub-skills of CVS. These findings indicate that CVS and science content knowledge are closely related within secondary school science contexts. In addition, the findings emphasize that students show various distinct patterns of CVS skills. The identified skill patterns can inform researchers and science educators about the CVS skills that students typically show and thus can be utilized in inquiry activities in different school grades, while the CVS skills students are lacking might be trained in focused interventions. 相似文献
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Tenko Raykov George A. Marcoulides Siegfried Gabler Youngjun Lee 《Structural equation modeling》2017,24(3):468-474
A latent variable modeling method for testing criterion correlations with measurement error terms in multicomponent measuring instruments is outlined. The approach is based on an application of the Benjamini–Hochberg multiple testing procedure and can be used when assumptions of validity estimation related procedures need to be examined. The method also allows studying the extent to which criterion validity coefficients might be due to the relationship between a presumed underlying latent construct evaluated by a psychometric scale and a criterion variable, or could be a consequence of the relation between measurement error in the overall scale score and the criterion. The discussed procedure is widely applicable with popular latent variable modeling software, and is illustrated using a numerical example. 相似文献
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In the last decades there has been an increasing interest in nonlinear latent variable models. Since the seminal paper of Kenny and Judd, several methods have been proposed for dealing with these kinds of models. This article introduces an alternative approach. The methodology involves fitting some third-order moments in addition to the means and covariances. This article discusses how the model equations can be formulated and how several standard tests, like the model fit and Lagrange multiplier tests, can be performed. The new method compares favorably with the maximum likelihood method in several studies and can provide evidence of interaction that earlier approaches might ignore. 相似文献
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A Second-Order Conditionally Linear Mixed Effects Model With Observed and Latent Variable Covariates
A conditionally linear mixed effects model is an appropriate framework for investigating nonlinear change in a continuous latent variable that is repeatedly measured over time. The efficacy of the model is that it allows parameters that enter the specified nonlinear time-response function to be stochastic, whereas those parameters that enter in a nonlinear manner are common to all subjects. In this article we describe how a variant of the Michaelis-Menten (M-M) function can be fit within this modeling framework using Mplus 6.0. We demonstrate how observed and latent covariates can be incorporated to help explain individual differences in growth characteristics. Features of the model including an explication of key analytic decision points are illustrated using longitudinal reading data. To aid in making this class of models accessible, annotated Mplus code is provided. 相似文献
15.
Tenko Raykov Philip B. Gorelick Anna Zajacova George A. Marcoulides 《Structural equation modeling》2017,24(6):926-935
Analysis and modeling of time to event data have been traditionally associated with nonparametric, semiparametric, or parametric statistical frameworks. Recent advances in latent variable modeling have additionally provided unique analytic opportunities to methodologists and substantive researchers interested in survival time modeling. As a consequence, discrete time survival analyses can now be readily carried out using latent variable modeling, an approach that offers substantively important extensions to conventional survival models. Using data from the Health and Retirement Study, the discussed approach is applied to the study of the increasingly prominent vascular depression hypothesis in gerontology, geriatrics, and aging research, allowing examination of the unique predictive power of depression with respect to time to stroke in middle-aged and older adults. 相似文献
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Gray's neurological theory of anxiety (1982, 1990; Gray & McNaughton, 2000) predicts that state anxiety will decrease with continuous exposure to a fear arousing stimulus. Previous studies of psychological and physiological state anxiety patterns during public speaking have reported a pattern of progressively decreasing anxiety levels consistent with this phenomenon, known as habituation. In the current report, the extent to which the state anxiety behaviors of speakers conform to the habituation pattern is examined. In the first of two studies, 30 novice speakers presented informative speeches to audiences of 18 to 20 fellow students. These speeches were videotaped and replayed in their entirety for observers (N=30) who rated the severity of each performer's speech anxiety behaviors. In the second study, each videotaped presentation was divided into one‐minute segments and presented in random order to a new set of observers (N=25). Procedures in the second study were designed to control for rater expectations that state anxiety would decline over time. Overall, behavioral measures of public speaking state anxiety displayed a continually declining pattern associated with habituation. 相似文献
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A Second-Order Conditionally Linear Mixed Effects Model With Observed and Latent Variable Covariates
Jeffrey R. Harring Nidhi Kohli Rebecca D. Silverman Deborah L. Speece 《Structural equation modeling》2013,20(1):118-136
A conditionally linear mixed effects model is an appropriate framework for investigating nonlinear change in a continuous latent variable that is repeatedly measured over time. The efficacy of the model is that it allows parameters that enter the specified nonlinear time-response function to be stochastic, whereas those parameters that enter in a nonlinear manner are common to all subjects. In this article we describe how a variant of the Michaelis–Menten (M–M) function can be fit within this modeling framework using Mplus 6.0. We demonstrate how observed and latent covariates can be incorporated to help explain individual differences in growth characteristics. Features of the model including an explication of key analytic decision points are illustrated using longitudinal reading data. To aid in making this class of models accessible, annotated Mplus code is provided. 相似文献
18.
《Structural equation modeling》2013,20(2):287-291
In a recent note in the Teacher's Corner of this journal, de Jong (1999) proposed a method for computing hierarchical or fixed-order regressions in the context of latent variables. The essence of this approach is to decompose the predictor variables in the regression into orthogonal components based on a Cholesky decomposition and to regress the dependent variable on these orthogonal components. The components may be conceived of as phantom factors that do not have their own indicators. Because the idea of sequential entry of predictors in a latent variable regression framework seems generally to be unknown, the approach was developed by de Jong for latent variable regressions. However, it equally can be used for observed variable regression or path models. In this article we show that the phantom factors are unnecessary to achieve the objectives of a hierarchical regression. We give a direct approach that is equivalent to de Jong's approach. 相似文献
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This study identified engagement profiles and examined their relations to student characteristics (gender, grade, socioeconomic status) as well as mathematics and reading achievement among elementary students attending urban schools in the southeastern part of the United States (N = 564). Using latent profile analysis, four engagement profiles were identified including a Moderately Engaged, Globally Disengaged, Affectively Disengaged, and Behaviorally Disengaged profile. Subsequent analyses showed that grade level was a statistically significant predictor of profile membership, and the Moderately Engaged profile was associated with higher mathematics achievement compared to the Affectively Disengaged profile. Results contribute to the growing body of person-centered work that indicates that students’ engagement cluster into unique configurations of global, behavioral, affective, cognitive, and social engagement, which have important implications for their academic achievement. 相似文献
20.
建立了一类具有变化潜伏期的水源性疾病数学模型,得到了水源性疾病流行的阈值R0（基本再生数）.利用LaSalle不变集原理,通过构造新的Liapunov函数证明了平衡点的全局稳定性：当R0≤1时,系统的无病平衡点p0是全局渐近稳定的;当R0＞1时,系统的地方病平衡点p＊是全局渐近稳定的.最后利用数值模拟说明结论的正确性. 相似文献