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1.
This study examined the performance of the weighted root mean square residual (WRMR) through a simulation study using confirmatory factor analysis with ordinal data. Values and cut scores for the WRMR were examined, along with a comparison of its performance relative to commonly cited fit indexes. The findings showed that WRMR illustrated worse fit when sample size increased or model misspecification increased. Lower (i.e., better) values of WRMR were observed when nonnormal data were present, there were lower loadings, and when few categories were analyzed. WRMR generally illustrated expected patterns of relations to other well-known fit indexes. In general, a cutoff value of 1.0 appeared to work adequately under the tested conditions and the WRMR values of “good fit” were generally in agreement with other indexes. Users are cautioned that when the fitted model is misspeficifed, the index might provide misleading results under situations where extremely large sample sizes are used. 相似文献
2.
Oksana B. Korobko Cees A. W. Glas Roel J. Bosker Johan W. Luyten 《Journal of Educational Measurement》2008,45(2):139-157
Methods are presented for comparing grades obtained in a situation where students can choose between different subjects. It must be expected that the comparison between the grades is complicated by the interaction between the students' pattern and level of proficiency on one hand, and the choice of the subjects on the other hand. Three methods based on item response theory (IRT) for the estimation of proficiency measures that are comparable over students and subjects are discussed: a method based on a model with a unidimensional representation of proficiency, a method based on a model with a multidimensional representation of proficiency, and a method based on a multidimensional representation of proficiency where the stochastic nature of the choice of examination subjects is explicitly modeled. The methods are compared using the data from the Central Examinations in Secondary Education in the Netherlands. The results show that the unidimensional IRT model produces unrealistic results, which do not appear when using the two multidimensional IRT models. Further, it is shown that both the multidimensional models produce acceptable model fit. However, the model that explicitly takes the choice process into account produces the best model fit. 相似文献
3.
In order to sufficiently exploit the advantages of different signal processing methods, such as wavelet transformation (WT), artificial neural networks (ANN) and expert rules (ER), a synthesized multi-method was introduced to detect and classify the epileptic waves in the EEG data. Using this method, at first, the epileptic waves were detected from pre-processed EEG data at different scales by WT, then the characteristic parameters of the chosen candidates of epileptic waves were extracted and sent into the well-trained ANN to identify and classify the true epileptic waves,and at last, the detected epileptic waves were certificated by ER. The statistic results of detection and classification show that, the synthesized multi-method has a good capacity to extract signal features and to shield the signals from the random noise. This method is especially fit for the analysis of the biomedical signals in biomedical engineering which are usually non-placid and nonlinear. 相似文献
4.
Herbert W. Marsh 《Journal of Educational Measurement》1993,30(2):157-183
The purpose of this investigation is to evaluate structural equation models (SEMs) for measures of the same construct collected on multiple occasions (one-variable, multiwave panel studies). Simplex models hypothesize that a measure at any one wave is substantially influenced by the measure at the 0immediately preceding wave; correlations between the same construct measured on different occasions are predicted to decline systematically as the number of intervening occasions increases. Alternatively, a one-factor model posits that a person's score at any one time is a function of some underlying "true" score and a random disturbance that is idiosyncratic to the time; no temporal ordering of correlations is assumed. Both the simplex and one-factor models can befit when there is only a single indicator of each construct at each wave (e.g., scale scores), but there are serious limitations to such models. Stronger models are possible when the same set of multiple indicators (e.g., the items that make up the scale) is measured at each wave. In Study 1, based on students' evaluations of teaching effectiveness collected over an 8-year period, one-factor models fit the data well, whereas simplex models did not. In Study 2, based on personality variables collected over a 4-year period during adolescence, one-factor models again provided an excellent fit to the data, whereas the simplex model did marginally poorer. The results challenge an overreliance on simplex models and demonstrate that a one-factor model is a potentially useful alternative that should be considered in multiwave studies. 相似文献
5.
Science motivation is an important factor that directly influences students’ science learning. Numerous studies have been undertaken to develop and validate questionnaire items for measuring students’ motivation in science learning. This study is the first longitudinal examination of the Chinese version of Science Motivation Questionnaire II (SMQ II-C) in a Chinese cultural context. Using two waves of surveys, we evaluated its internal structure validity and criterion-related validity. Results showed that at each time point, scores were internally consistent and the hypothesized five-factor model was confirmed as the best model fit for the data. Results of multigroup invariance revealed the structure of the SMQ II-C was equivalent within gender subgroups. Furthermore, the present study added longitudinal invariance evidence of the SMQ II-C by sampling two-time points. Overall, this study suggests the SMQ II-C is a robust instrument for evaluating Chinese high school students’ motivation to learn science. Furthermore, boys yielded higher scores than girls among all five subscales of science motivation and significant gender differences were observed in both waves. Implications and limitations of these results are discussed. 相似文献
6.
研究目的：创新要点：研究方法：重要结论：采用广义估计方程模型对存在时间相关件的事故频次数据进行建模,并与传统广义线性模型的估计效果进行对比。
通过广义估计方程来考虑事故频次建模中数据的时间相关性,从而提高参数估计准确度以及模型预测精度。基于4年高速公路交通事故频次数据,建立考虑时间相关性的广义估计方程以及传统的广义线性模型,并采用统计指标对模型效果进行对比。1．事故频次数据样本最对预测精度影响很大;2．广义估引方程能够有效考虑事故频次数据中存住的时间相关性;3．广义估计方程的参数估计比传统广义线性模型史准确,且精度更高。 相似文献
7.
张红霞 《安徽广播电视大学学报》2003,(3):47-51
TEM4听写采用的是较传统的数错扣分法。数错扣分法是负分法，其中存在一些问题。因此我们提出一种实验性的评分方法——部分得分制。实验数据有两组，分别采用TEM4听写评分制和新评分制。数据比较以及部分得分模型(Rasch模型之一)对实验量表效能的分析(如模型与数据拟合值、被试拟合值、信息函数等)说明，实验评分制能较好地测量大多数学生的听写水平。 相似文献
8.
Ji Hoon Song 《Performance Improvement Quarterly》2008,21(2):87-102
The primary purpose of this research is to explore the impacts of knowledge creation practices on organizational performance improvement. Research has been empirically assessed on the basis of the collected data from three Korean private organizations. The concept of knowledge creation theory was adapted as the theoretical framework of this research (Nonaka & Takeuchi, 1995). Structural equation modeling has been used in order to assess the fit of the hypothesized model with the collected data. The result of the confirmatory factor analysis suggests that the hypothesized measurement model is a reliable and valid construct in the Korean context; multiple regression analysis reveals that knowledge creation practices have a positive and strong influence on performance improvement. Conclusions, limitations, and implications for human resource development are discussed. 相似文献
9.
Wave breaking plays an important role in sedi- ment transport and beach profile change. Breaking waves exhibit various patterns, principally depending on the incident wave steepness and the beach slope. The breaking patterns range from the relatively con- trolled spilling type to the violent and sudden plunging breaker type. The breaker patterns are classified into 3 or 4 categories. Some criteria for breaker pat- terns[1] are given in Tab. 1. Several wave decay models have been proposed to d… 相似文献
10.
Model fit indices are being increasingly recommended and used to select the number of factors in an exploratory factor analysis. Growing evidence suggests that the recommended cutoff values for common model fit indices are not appropriate for use in an exploratory factor analysis context. A particularly prominent problem in scale evaluation is the ubiquity of correlated residuals and imperfect model specification. Our research focuses on a scale evaluation context and the performance of four standard model fit indices: root mean square error of approximate (RMSEA), standardized root mean square residual (SRMR), comparative fit index (CFI), and Tucker–Lewis index (TLI), and two equivalence test-based model fit indices: RMSEAt and CFIt. We use Monte Carlo simulation to generate and analyze data based on a substantive example using the positive and negative affective schedule (N = 1,000). We systematically vary the number and magnitude of correlated residuals as well as nonspecific misspecification, to evaluate the impact on model fit indices in fitting a two-factor exploratory factor analysis. Our results show that all fit indices, except SRMR, are overly sensitive to correlated residuals and nonspecific error, resulting in solutions that are overfactored. SRMR performed well, consistently selecting the correct number of factors; however, previous research suggests it does not perform well with categorical data. In general, we do not recommend using model fit indices to select number of factors in a scale evaluation framework. 相似文献
11.
David W. Chan 《Roeper Review》2013,35(4):203-209
The relationships among adjustment problems, self‐efficacy, and psychological distress were investigated in a sample of 207 Chinese gifted students in Hong Kong. A mediation‐effect model specifying that adjustment problems had an effect on psychological distress mediated by self‐efficacy was hypothesized and tested using structural equation modeling procedures. For comparison, a direct‐effect model and a direct‐and‐mediation‐effect model were also fitted to the data. The results indicated that the direct‐and‐mediation‐effect model provided the best and a reasonably adequate fit, suggesting that the effects of adjustment problems on psychological distress could be direct, but more importantly the effects could also be mediated by self‐efficacy. Implications of the findings for enhancing the self‐efficacy of students to promote their psychological well‐being are discussed. 相似文献
12.
How educational goals are conceptualized as a construct has implications for developing and evaluating educational programs and activities. The author used EQS 3.0 to test the factorial validity of 4 models of conceptualization of educational goals by conducting confirmatory factor analysis on empirical data collected from 1,134 education faculty members. The 4-factor model espoused by Goodlad fit the data best, and the participants wanted academic, vocational, personal, and social goals to be in relative harmony. Implications for educational theory, practice, and research are discussed. 相似文献
13.
Bernice Y.L. Wong Maureen Hoskyn Debbie Jai Patty Ellis Kim Watson 《Contemporary educational psychology》2008,33(4):757-784
Children in sixth grade randomly assigned to a teacher-made writing procedure anchored in the self-regulated strategy development (SRSD) model and training procedures were predicted to surpass children assigned to the comparison condition on dependent measures of writing clarity, organization, and cogency. The prediction was generally substantiated. The results suggest that the rate of change among individual children in the SRSD condition was faster than among children in the comparison condition on measures of clarity and organization. On the measure of cogency, findings showed that the rate of change among individuals in the SRSD condition compared to the comparison condition approached but did not reach statistical significance. Variance in growth parameters on the measure of writing clarity was statistically significant; however on the measure of organization, there was no substantive variation in individual growth parameters. Social validity data from all the children and teachers indicated the training was well received. The results are taken to support the efficacy of the SRSD model and training procedures. 相似文献
14.
为了解决氮氧化物分析仪转化炉转换效率估算问题,对现有氮氧化物转化效率计算模型进行定量分析。通过实验采集氮氧化物分析仪的历史检测数据,提出计算转化效率的动态修正模型,针对模型中的相关参数进行估计,并对两种模型的拟合优度加以比较。研究结果表明,相比于现有氮氧化物分析仪固有的计算模型,动态修正模型的残差平方和平均降低89.24%,多重可决系数接近1的程度平均增长88.64%,因而可以使分析仪对机动车尾气中的氮氧化物浓度检测更加准确可靠。 相似文献
15.
Rasch模型和IRT在学生成就测验统计分析中的对比研究 总被引：1，自引：0，他引：1
Rasch模型和项目反应理论的诞生推进了社会科学领域研究方法的变革。大多数学者认为,Rasch模型就是三参数IRT模型的特例。其实,Rasch模型不同于项目反应理论,其数据必须符合模型的先验理论。研究利用基于这两种理论假设开发的软件Winsteps和Multilog对学生成就测验进行统计分析,旨在揭示两种理论模型数据分析结果的异同之处,并探讨Winsteps软件在教育统计中的应用。 相似文献
16.
《Structural equation modeling》2013,20(2):213-232
In the past, several models have been developed for the estimation of the reliability and validity of measurement instruments from multitrait-multimethod (MTMM) experiments. Suggestions have been made for additive, multiplicative and correlated uniqueness models, whereas recently Coenders and Saris (2000) suggested a procedure to test these models against one another. In this article, the different models suggested for the analysis of MTMM matrixes have been compared for their fit to 87 data sets collected in the United States (Andrews, 1984; Rodgers, Andrews, & Herzog, 1992), Austria (Koltringer, 1995), and the Netherlands (Scherpenzeel & Saris, 1997). As most variables are categorical, the analysis has been carried out on the basis of polychoric-polyserial correlation coefficients and of Pearson correlations. The fit of the models based on polychoric correlations is much worse than the fit of models based on product moment correlations, but in both cases a model that assumes additive method effects fits most data sets better than the other models, including the so-called multiplicative models. 相似文献
17.
This paper presents the explosion cratering effects and their propagation laws of blast waves in dry standard sands using
a 450 g-t geotechnical centrifuge apparatus. Ten centrifuge model tests were completed with various ranges of explosive mass, burial
depth and centrifuge accelerations. Eleven accelerometers were installed to record the acceleration response in sand. The
dimensions of the explosion craters were measured after the tests. The results demonstrated that the relationship between
the dimensionless parameters of cratering efficiency and gravity scaled yield is a power regression function. Three specific
function equations were obtained. The results are in general agreement with those obtained by other studies. A scaling law
based on the combination of the π terms was used to fit the results of the ten model tests with a correlation coefficient of 0.931. The relationship can be
conveniently used to predict the cratering effects in sand. The results also showed that the peak acceleration is a power
increasing function of the acceleration level. An empirical exponent relation between the proportional peak acceleration and
distance is proposed. The propagation velocity of blast waves is found to be ranged between 200 and 714 m/s. 相似文献
18.
In structural equation models, outliers could result in inaccurate parameter estimates and misleading fit statistics when using traditional methods. To robustly estimate structural equation models, iteratively reweighted least squares (IRLS; Yuan & Bentler, 2000) has been proposed, but not thoroughly examined. We explore the large-sample properties of IRLS and its effect on parameter recovery, model fit, and aberrant data identification. A parametric bootstrap technique is proposed to determine the tuning parameters of IRLS, which results in improved Type I error rates in aberrant data identification, for data sets generated from homogenous populations. Scenarios concerning (a) simulated data, (b) contaminated data, and (c) a real data set are studied. Results indicate good parameter recovery, model fit, and aberrant data identification when noisy observations are drawn from a real data set, but lackluster parameter recovery and identification of aberrant data when the noise is parametrically structured. Practical implications and further research are discussed. 相似文献
19.
James A. Fitzgerald 《Journal of Experimental Education》2013,81(4):364-367
Many mechanistic rules of thumb for evaluating the goodness of fit of structural equation models (SEM) emphasize model parsimony; all other things being equal, a simpler, more parsimonious model with fewer estimated parameters is better than a more complex model Although this is usually good advice, in the present article a heuristic counterexample is demonstrated in which parsimony as typically operationalized in indices of fit may be undesirable. Specifically, in simplex models of longitudinal data, the failure to include correlated uniquenesses relating the same indicators administered on different occasions will typically lead to systematically inflated estimates of stability. Although simplex models with correlated uniquenesses are substantially less parsimonious and may be unacceptable according to mechanistic decision rules that penalize model complexity, it can be argued a priori that these additional parameter estimates should be included. Simulated data . are used to support this claim and to evaluate the behavior of a variety of fit indices and decision rules. The results demonstrate the validity of Bollen and Long’s (1993) conclusion that “test statistics and fit indices are very beneficial, but they are no replacement for sound judgment and substantive expertise” (p. 8). 相似文献