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1.
Latent profile analysis (LPA) has become a popular statistical method for modeling unobserved population heterogeneity in cross-sectionally sampled data, but very few empirical studies have examined the question of how well enumeration indexes accurately identify the correct number of latent profiles present. This Monte Carlo simulation study examined the ability of several classes of enumeration indexes to correctly identify the number of latent population profiles present under 3 different research design conditions: sample size, the number of observed variables used for LPA, and the separation distance among the latent profiles measured in Mahalanobis D units. Results showed that, for the homogeneous population (i.e., the population has k = 1 latent profile) conditions, many of the enumeration indexes used in LPA were able to correctly identify the single latent profile if variances and covariances were freely estimated. However, for a heterogeneous population (i.e., the population has k = 3 distinct latent profiles), the correct identification rate for the enumeration indexes in the k = 3 latent profile conditions was typically very low. These results are compared with the previous cross-sectional mixture modeling studies, and the limitations of this study, as well as future cross-sectional mixture modeling and enumeration index research possibilities, are discussed.  相似文献   

2.
Relatively few empirical studies have examined the performance of enumeration indices in correctly identifying longitudinal population heterogeneity when present, and these studies have produced mixed results. In light of these findings, Muthén (2003) suggested that the inclusion of time-invariant (antecedent) and time-varying (concurrent) covariates, as well as allowing the extracted growth mixture classes to predict a distal outcome (consequent covariate), could improve the performance of enumeration indices. This Monte Carlo simulation study examined the performance of a large set of enumeration indices within these generalized growth mixture model (GGMM) conditions, as suggested by Muthén, by manipulating 4 design conditions: (a) sample size, (b) separation distance between adjacent latent growth trajectories, (c) growth trajectory membership proportions, and (d) the amount of mixture model variance explained by the covariates. The findings suggest: (a) at smaller (N = 500) sample sizes, enumeration indices were much more likely to select an incorrect model than the correct one, (b) at larger (N = 3,000) sample sizes, correct model identification occurred only in the largest separation distance and trajectory membership equality conditions, and (c) the inclusion of covariates had a negligible effect at smaller sample sizes, but covariate inclusion had a more favorable effect on data generation model identification in the largest sample size, largest trajectory separation distance, and equal trajectory membership proportions conditions. Suggestions for researchers and future empirical study possibilities are discussed.  相似文献   

3.
This Monte Carlo simulation adds to the growing body of enumeration index performance research in continuous response variable mixture models by addressing the issue of the performance of these indexes in discrete-time survival mixture analysis (DTSMA) models. Results showed that although all enumeration indexes performed very well in identifying a homogeneous DTSMA model (i.e., = 1 hazard function in the sample data), the findings also showed that the enumeration indexes performed poorly in identifying the correct number of unobserved hazard functions present in a heterogeneous (i.e., = 3) DTSMA model. More important, the performance of the enumeration indexes for the heterogeneous DTSMA models did not improve as the sample size, the effect of time-invariant covariates, or adjacent hazard function separation distance increased, which is inconsistent with some previous Monte Carlo simulation results. The limitations of this Monte Carlo simulation study and future empirical investigation possibilities are both discussed.  相似文献   

4.
Piecewise GMM with unknown turning points is a new procedure to investigate heterogeneous subpopulations' growth trajectories consisting of distinct developmental phases. Unlike the conventional PGMM, which relies on theory or experiment design to specify turning points a priori, the new procedure allows for an optimal location of turning points based on data. The advantage of the procedure has gained increasing attention in educational and behavioral research, but a major challenging issue, class enumeration performance of the model, has not yet been investigated. The current simulation study compared the performance of PGMMs with unknown turning points in identifying the correct number of latent classes under both Bayesian and ML/EM estimation methods.  相似文献   

5.
Mixture modeling is a widely applied data analysis technique used to identify unobserved heterogeneity in a population. Despite mixture models' usefulness in practice, one unresolved issue in the application of mixture models is that there is not one commonly accepted statistical indicator for deciding on the number of classes in a study population. This article presents the results of a simulation study that examines the performance of likelihood-based tests and the traditionally used Information Criterion (ICs) used for determining the number of classes in mixture modeling. We look at the performance of these tests and indexes for 3 types of mixture models: latent class analysis (LCA), a factor mixture model (FMA), and a growth mixture models (GMM). We evaluate the ability of the tests and indexes to correctly identify the number of classes at three different sample sizes (n = 200, 500, 1,000). Whereas the Bayesian Information Criterion performed the best of the ICs, the bootstrap likelihood ratio test proved to be a very consistent indicator of classes across all of the models considered.  相似文献   

6.
SYNOPSIS

Objective . Most parents manage some degree of parenting stress without serious concerns, but young mothers experience parenting stress at higher levels than adult mothers; high parenting stress is problematic due to its association with children’s socioemotional and behavior problems and the increased likelihood of maltreatment. Understanding the circumstances that precipitate or mitigate parents’ stress can have lasting impacts for child well-being. Extant research fails to account for both longitudinal and individual variation in young mothers’ parenting stress, leading to equivocal findings about the nature of mothers’ parenting stress trajectories across early childhood. Design . The present study used growth mixture modeling (GMM) to model the trajectories of 544 first-time young mothers’ parenting stress from children’s infancy to school-age. We considered how protective factors (i.e., social support) and psychological vulnerabilities (i.e., depression) experienced during the transition to parenthood were associated with parenting stress trajectories and variation within trajectories when children were of school-age. Results . GMM identified three trajectories of parenting stress: “low stable”, “high increasing”, and “high decreasing.” Protective factors were related to low and decreasing patterns of parenting stress, whereas psychological vulnerabilities were associated with higher parenting stress patterns. Conclusions . This study has implications for programs and services that help young mothers cope with the demands of parenting and reduce parenting stress.  相似文献   

7.
The aim of this study was to determine how trajectory clusters of social status (social preference and perceived popularity) and behavior (direct aggression and prosocial behavior) from age 9 to age 14 predicted adolescents’ bullying participant roles at age 16 and 17 (= 266). Clusters were identified with multivariate growth mixture modeling (GMM). The findings showed that participants’ developmental trajectories of social status and social behavior across childhood and early adolescence predicted their bullying participant role involvement in adolescence. Practical implications and suggestions for further research are discussed.  相似文献   

8.
This study investigated the development of relational aggression (RA) in a sample of Chinese youth (= 2,274, 52% boys) from fourth (Mage = 10.27 years) to ninth grade. Using latent class growth analysis, four trajectories were identified for both peer- and teacher-rated RA: a no aggression trajectory, a low-increasing trajectory, a moderate-decreasing trajectory, and a chronically high trajectory. Chronically high RA showed a chronicity effect on adolescent peer acceptance, rejection, and rule-breaking behaviors. Adolescents showed worse adjustment as RA increased, but they did not necessarily evidence significant improvement in adjustment even if their RA decreased. Findings reveal the maladaptive nature of RA and highlight the importance of considering cultural context in understanding RA.  相似文献   

9.
BackgroundUnderstanding different longitudinal patterns of traumatic stress reactions in children exposed to intimate partner violence (IPV) can promote early identification of at-risk children.ObjectiveOur study aims to explore trajectories of traumatic stress reactions following childhood IPV exposure, and their relation with parental traumatic stress and child emotional security in the interparental subsystem.Participants and SettingThe sample comprised 303 children (age 3–10, M = 6.20) from families referred to institutions for IPV. Data were collected at home.MethodsThree waves of parent-reported questionnaire data were analyzed using latent class growth analysis and linear regression.ResultsFive trajectories were identified: ‘resilient’, ‘moderate stable’, ‘struggling’, ‘improving’, and ‘elevated adjusting’. Only the ‘struggling’ trajectory had dysfunctional symptom levels at the final wave. Higher parental traumatic stress predicted ‘improving’ trajectory membership (β = 0.17, p = .033), whereas lower parental traumatic stress (β = −0.20, p = .003) and child emotional insecurity (β = −0.45, p = < .001) predicted ‘resilient’ trajectory membership. Higher child emotional insecurity predicted membership in trajectories with higher initial traumatic stress (improving: β = 0.26, p < .001; struggling: β = 0.31, p < .001; elevated adjusting: β = 0.27, p < .001). Child emotional security did not buffer the effect of parental traumatic stress on likelihood of dysfunctional trajectory membership (β = 0.04, p =.380).ConclusionsChildren exposed to IPV show different trajectories of traumatic stress reactions, partly corresponding to trajectories identified in other populations. Child emotional security and parental traumatic stress predict trajectory membership.  相似文献   

10.
This study examined the performance of 4 correlation-based fit indexes (marginal and conditional pseudo R 2s; average and conditional concordance correlations) in detecting misspecification in mean structures in growth curve models. Their performance was also compared to that of 4 traditional SEM fit indexes. We found that the marginal pseudo R 2 and average concordance correlation were able to detect misspecification in the marginal mean structure (average change trajectory). The conditional pseudo R 2 and concordance correlation could detect misspecification when it occurred in the conditional mean structure (individual change trajectory) or in both mean structures. Compared to the SEM fit indexes, the correlation-based fit indexes were more robust to sample size but were less robust to data properties such as magnitude of population mean and measurement error. Theoretical and practical implications of the results and directions for future research are discussed.  相似文献   

11.
This study examined trajectories of ethnic–racial identity (ERI) and autonomy development among Mexican‐origin adolescent females in the United States (= 181; Mage at Wave 1 = 16.80 years, SD = 1.00) as they transitioned through the first 5 years of parenthood. Trajectories of ERI and autonomy also were examined in relation to psychosocial functioning. Unconditional latent growth models indicated significant growth in autonomy, ERI resolution, and ERI affirmation from middle to late adolescence. Conditional latent growth models indicated that autonomy and ERI exploration growth trajectories were positively associated with psychosocial adjustment. Although adolescent mothers are experiencing transitions that are not normative during adolescence, they also engage in normative developmental processes, and their engagement in such processes is linked with better adjustment.  相似文献   

12.
The purpose of this study was to examine the impact of misspecifying a growth mixture model (GMM) by assuming that Level-1 residual variances are constant across classes, when they do, in fact, vary in each subpopulation. Misspecification produced bias in the within-class growth trajectories and variance components, and estimates were substantially less precise than those obtained from a correctly specified GMM. Bias and precision became worse as the ratio of the largest to smallest Level-1 residual variances increased, class proportions became more disparate, and the number of class-specific residual variances in the population increased. Although the Level-1 residuals are typically of little substantive interest, these results suggest that researchers should carefully estimate and report these parameters in published GMM applications.  相似文献   

13.
Deciding on the number of “classes” has been the most prominent and most debated challenge in finite mixture modeling. Recently, a novel strategy has been proposed to select the best model in finite mixture modeling: a k-fold cross-validation approach. However, this approach has not been systematically evaluated, which makes the performance of the k-fold cross-validation approach for model selection in finite mixture modeling largely unknown. Thus, the main motivation for conducting the current work is to systematically evaluate the performance of the k-fold cross-validation approach for model selection in the context of Growth Mixture Modeling. Results revealed that the performance of the k-fold cross-validation approach for model selection in GMM is generally unsatisfactory, and it only performs reasonably well under the condition of very large class separation.  相似文献   

14.
Growth mixture modeling (GMM) is a useful statistical method for longitudinal studies because it includes features of both latent growth modeling (LGM) and finite mixture modeling. This Monte Carlo simulation study explored the impact of ignoring 3 types of time series processes (i.e., AR(1), MA(1), and ARMA(1,1)) in GMM and manipulated the separation of the latent classes, the strength of the time series process, and whether the errors conformed to the time series process in 1 or 2 latent classes. The results showed that omitting time series processes resulted in more serious bias in parameter estimation as the distance between classes increased. However, when the class distances were small, ignoring time series processes contributed to the selection of the correct number of classes. When the GMM models correctly specified the time series process, only models with an AR(1) time series process produced unbiased parameter estimates in most conditions. It was also found that among design factors manipulated, the distance between classes prominently affected the identification of the number of classes and parameter estimation.  相似文献   

15.
This study identified changes in Korean and heritage language proficiencies across five waves (2011–2015) and examined the association between linguistic acculturation trajectories and adjustment (2016) among Korean adolescents with immigrant family backgrounds (N = 1441; 51.21% female; Mage(baseline) = 9.97). All adolescents were from multiethnic families with 91.65% comprising a non-Korean Asian mother (e.g., Japan, Philippines, China, Thailand) and Korean father. Parallel process latent class growth modeling and multivariate regression analysis were conducted to estimate the trajectories of linguistic acculturation and their effects on adolescents' future adjustment. Linguistic acculturation trajectories were classified into three latent groups. Bilingual adolescents demonstrated better adjustment over adolescents in other trajectories. Findings highlight the importance of considering patterns of change in linguistic acculturation for understanding Korean multicultural adolescents' adjustment.  相似文献   

16.
This study investigated the extent to which class-specific parameter estimates are biased by the within-class normality assumption in nonnormal growth mixture modeling (GMM). Monte Carlo simulations for nonnormal GMM were conducted to analyze and compare two strategies for obtaining unbiased parameter estimates: relaxing the within-class normality assumption and using data transformation on repeated measures. Based on unconditional GMM with two latent trajectories, data were generated under different sample sizes (300, 800, and 1500), skewness (0.7, 1.2, and 1.6) and kurtosis (2 and 4) of outcomes, numbers of time points (4 and 8), and class proportions (0.5:0.5 and 0.25:0.75). Of the four distributions, it was found that skew-t GMM had the highest accuracy in terms of parameter estimation. In GMM based on data transformations, the adjusted logarithmic method was more effective in obtaining unbiased parameter estimates than the use of van der Waerden quantile normal scores. Even though adjusted logarithmic transformation in nonnormal GMM reduced computation time, skew-t GMM produced much more accurate estimation and was more robust over a range of simulation conditions. This study is significant in that it considers different levels of kurtosis and class proportions, which has not been investigated in depth in previous studies. The present study is also meaningful in that investigated the applicability of data transformation to nonnormal GMM.  相似文献   

17.
Children (n = 122) and adults (n = 200) with dyslexia completed rapid automatic naming (RAN) letters, rapid automatic switching (RAS) letters and numbers, executive function (inhibition, verbal fluency), and phonological working memory tasks. Typically developing 3rd (n = 117) and 5th (n = 103) graders completed the RAS task. Instead of analyzing RAN/RAS results the usual way (total time), growth mixture modeling assessed trajectories of successive times for naming 10 symbols in each of five rows. For all three samples and both RAN and RAS, two latent classes were identified. The “faster” class performed slowly on the first row and increased time by small increments on subsequent rows. The “slower” latent class performed more slowly on the first row, and children, but not adults, increased time by larger increments on subsequent rows. For children, both the initial row (automaticity index) and slope (sustained controlled processing index) of the trajectory differentiated the classes. For adults, only the initial row separated the classes. The longest time was on row 3 for RAN and row 4 for RAS. For the typically developing 5th graders, close in age to the children with dyslexia, the trajectories were flatter than for children with dyslexia and only the slower class (4%) showed the peak on row 4. For children with dyslexia, inhibition predicted RAN slope within the slower latent class and phonological working memory predicted RAS slope for both latent classes. For adults with dyslexia, inhibition and phonological working memory differentiated both latent classes on RAN intercept and RAS slope. Taken together, RAN, which may assess the phonological loop of working memory, and RAS, which may assess the central executive in working memory, may explain the timing deficit in dyslexia in sustaining coordinated orthographic-phonological processing over time. This research was supported by Grant Ns. P50 33812 and R01 HD25858 from the National Institute of Child Health and Human Development, Virginia W. Berninger, PI.  相似文献   

18.
This Monte Carlo study investigated the impacts of measurement noninvariance across groups on major parameter estimates in latent growth modeling when researchers test group differences in initial status and latent growth. The average initial status and latent growth and the group effects on initial status and latent growth were investigated in terms of Type I error and bias. The location and magnitude of noninvariance across groups was related to the location and magnitude of bias and Type I error in the parameter estimates. That is, noninvariance in factor loadings and intercepts was associated with the Type I error inflation and bias in the parameter estimates of the slope factor (or latent growth) and the intercept factor (or initial status), respectively. As noninvariance became large, the degree of Type I error and bias also increased. On the other hand, a correctly specified second-order latent growth model yielded unbiased parameter estimates and correct statistical inferences. Other findings and implications on future studies were discussed.  相似文献   

19.
This study investigates heterogeneity in adolescents' trajectories of global self‐esteem (GSE) and the relations between these trajectories and facets of the interpersonal, organizational, and instructional components of students' school life. Methodologically, this study illustrates the use of growth mixture analyses, and how to obtain proper student‐level effects when there are multiple schools, but not enough to support multilevel analyses. This study is based on a 4‐year, six‐measurement‐point, follow‐up of 1,008 adolescents (Mage = 12.6 years, SD = 0.6 at Time 1.) The results show four latent classes presenting elevated, moderate, increasing, and low trajectories defined based on GSE levels and fluctuations. The results show that GSE becomes trait‐like as it increases and that school life effects, moderated by gender, played an important role in predicting membership in these trajectories.  相似文献   

20.
Tracing developmental pathways of immigrant-origin adolescents, this 3-year longitudinal study (2012–2015) examined within-person changes in cultural orientations and their consequences for school adjustment. Multivariate latent growth mixture modeling confirmed multiple pathways of integration, revealing variable acculturative changes along dual trajectories of heritage and mainstream orientations among European-origin (N = 592, Mage = 14.45, 55.1% boys) and Turkish- and Moroccan-origin adolescents (N = 1269, Mage = 14.70, 53.1% boys). Two trajectories for European-origin adolescents differed in heritage orientations (high decreasing and low increasing); for Turkish- and Moroccan-origin adolescents, three trajectories differed in mainstream orientations (high stable, low increasing, and high decreasing). Acculturative change affected aspects of later school adjustment: European-origin adolescents in high heritage orientation trajectories reported more belonging and emotional engagement; Turkish- and Moroccan-origin adolescents in high mainstream orientation trajectories reported more behavioral engagement.  相似文献   

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