共查询到20条相似文献，搜索用时 31 毫秒
1.
Mediation is one concept that has shaped numerous theories. The list of problems associated with mediation models, however, has been growing. Mediation models based on cross-sectional data can produce unexpected estimates, so much so that making longitudinal or causal inferences is inadvisable. Even longitudinal mediation models have faults, as parameter estimates produced by these models are specific to the lag between observations, leading to much debate over appropriate lag selection. Using continuous time models (CTMs) rather than commonly employed discrete time models, one can estimate lag-independent parameters. We demonstrate methodology that allows for continuous time mediation analyses, with attention to concepts such as indirect and direct effects, partial mediation, the effect of lag, and the lags at which relations become maximal. A simulation compares common longitudinal mediation methods with CTMs. Reanalysis of a published covariance matrix demonstrates that CTMs can be fit to data used in longitudinal mediation studies. 相似文献
2.
《教育实用测度》2013,26(2):163-183
When low-stakes assessments are administered, the degree to which examinees give their best effort is often unclear, complicating the validity and interpretation of the resulting test scores. This study introduces a new method, based on item response time, for measuring examinee test-taking effort on computer-based test items. This measure, termed response time effort (RTE), is based on the hypothesis that when administered an item, unmotivated examinees will answer too quickly (i.e., before they have time to read and fully consider the item). Psychometric characteristics of RTE scores were empirically investigated and supportive evidence for score reliability and validity was found. Potential applications of RTE scores and their implications are discussed. 相似文献
3.
Valuable methods have been developed for incorporating ordinal variables into structural equation models using a latent response variable formulation. However, some model parameters, such as the means and variances of latent factors, can be quite difficult to interpret because the latent response variables have an arbitrary metric. This limitation can be particularly problematic in growth models, where the means and variances of the latent growth parameters typically have important substantive meaning when continuous measures are used. However, these methods are often applied to grouped data, where the ordered categories actually represent an interval-level variable that has been measured on an ordinal scale for convenience. The method illustrated in this article shows how category threshold values can be incorporated into the model so that interpretation is more meaningful, with particular emphasis given to the application of this technique with latent growth models. 相似文献
4.
Item nonresponses are prevalent in standardized testing. They happen either when students fail to reach the end of a test due to a time limit or quitting, or when students choose to omit some items strategically. Oftentimes, item nonresponses are nonrandom, and hence, the missing data mechanism needs to be properly modeled. In this paper, we proposed to use an innovative item response time model as a cohesive missing data model to account for the two most common item nonresponses: not-reached items and omitted items. In particular, the new model builds on a behavior process interpretation: a person chooses to skip an item if the required effort exceeds the implicit time the person allocates to the item (Lee & Ying, 2015; Wolf, Smith, & Birnbaum, 1995), whereas a person fails to reach the end of the test due to lack of time. This assumption was verified by analyzing the 2015 PISA computer-based mathematics data. Simulation studies were conducted to further evaluate the performance of the proposed Bayesian estimation algorithm for the new model and to compare the new model with a recently proposed “speed-accuracy + omission” model (Ulitzsch, von Davier, & Pohl, 2019). Results revealed that all model parameters could recover properly, and inadequately accounting for missing data caused biased item and person parameter estimates. 相似文献
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6.
Time sampling: a methodological critique 总被引：5，自引：0，他引：5
Numerous developmental studies of social behavior employ an observational technique called time sampling. This technique is used to estimate the frequencies and proportions of time that actual behaviors occur and to measure group or individual differences. By contrasting time sampling to continuous sampling, we demonstrate that (a) time sampling is inaccurate for estimating actual durations or frequencies of behavior, and (b) resulting individual and/or group differences can change depending on whether time sampling or continuous sampling is used. Error rates are particularly high when the total bout lengths of the actual behaviors are short (as in mother-infant interactions) and/or when interval length is long. Because the majority of mother and infant behaviors are short in bout length (less than 60 sec), when percent error is the greatest, we suggest that alternative sampling methods that have proven validity be used in future studies (e.g., scan, point, or continuous sampling). 相似文献
7.
This paper provides findings of research on school effectiveness and discusses implications for evaluation in Brazil and Portugal. Most findings reported over the last decade have been published in Brazilian or Portuguese refereed journals. Thus, a brief literature review of such studies enables that knowledge to reach international scholars and researchers. The magnitude of school effects obtained from longitudinal and cross-sectional data modelling is presented and discussed. In particular, a value-added approach based on multilevel models is used to explore consistency across models with different controlling variables and across different curricular contents, and stability over time. The results show a great deal of regional disparities regarding educational outcomes that are related to pupils’ socioeconomic and prior achievement heterogeneity. In addition, evidence is given for stronger school effects in primary than in lower secondary education, larger amplitude of the variance partition coefficient in primary than in lower secondary education, stronger consistency of value-added estimates across models with different controlling variables and moderate consistency across different curricular contents. Weak-to-moderate stability of value-added estimates is also shown when yearly measured compared to when measured by cycles of education, and moderate-to-strong stability when measured in different curricular contents. Recommendations are outlined in terms of how the results could be used to mentoring evaluation in Portuguese speaking countries and enhance school improvement. 相似文献
8.
Experiments in captivity have provided evidence for social learning, but it remains challenging to demonstrate social learning
in the wild. Recently, we developed network-based diffusion analysis (NBDA; 2009) as a new approach to inferring social learning
from observational data. NBDA fits alternative models of asocial and social learning to the diffusion of a behavior through
time, where the potential for social learning is related to a social network. Here, we investigate the performance of NBDA
in relation to variation in group size, network heterogeneity, observer sampling errors, and duration of trait diffusion.
We find that observation errors, when severe enough, can lead to increased Type I error rates in detecting social learning.
However, elevated Type I error rates can be prevented by coding the observed times of trait acquisition into larger time units.
Collectively, our results provide further guidance to applying NBDA and demonstrate that the method is more robust to sampling
error than initially expected. Supplemental materials for this article may be downloaded from http://lb.psychonomic-journals.org/content/supplemental. 相似文献
9.
《Structural equation modeling》2013,20(4):599-612
This article is intended to complement previous research (Sivo, 1997; Sivo & Willson, 1998, in press) by discussing the propriety and practical advantages of specifying multivariate time series models in the context of structural equation modeling for time series and longitudinal panel data. Three practical considerations motivated this article. Unlike Marsh (1993), Sivo and Willson (2000) did not offer multiple indicator (latent order) equivalents to their autoregressive (AR), moving average (MA), and autoregressive-moving average (ARMA) models. Moreover, such models have yet to be discussed, despite Marsh's (1993) advocacy for multiple indicator models in general. Further motivating multiple indicator extensions of the AR, MA, and ARMA equivalent models is the fact that longitudinal studies often collect data on more than 1 related variable per occasion. Such multiple indicator models capitalize on 1 of the chief analytical advantages of structural equation modeling in that measurement error may be estimated directly. 相似文献
10.
This study investigates the relationships of domain-general cognitive abilities and domain-specific verbal and mathematical abilities to students' educational characteristics when two theoretically grounded, but competing structural models are applied. In the standard model, a single latent ability causes interindividual differences in the corresponding measures. In the nested-factor model, interindividual differences are caused by two independent cognitive abilities: general cognitive ability and domain-specific ability. The two models were examined using data from 29,386 ninth graders. The results show that findings on the relations between domain-specific abilities and students' socio-economic status, general school satisfaction, educational aspirations, domain-specific interests, and subject-specific grades may differ substantially depending on the structural model applied. Implications for educational research and measurement as well as for students' motivational and cognitive development are discussed. 相似文献
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刘俊 《沙洋师范高等专科学校学报》2005,6(2):82-84
人类的时间观亘古有之，但不同社会，不同化的人们对时间的理解和运用是不相同的。人们对时间的理解、建构、反应和解释的学科就是时间学，据研究，在化时间观里，非正式时间最能导致化冲突。 相似文献
13.
孔德凌 《咸阳师范学院学报》2006,21(5):26-30
对于周代嫁娶时间这一问题,《毛传》以为婚期当以秋冬为正时,郑玄笺《诗》、注《礼》却认为仲春二月为婚娶之正时。通过对《诗经》、《春秋》、《左传》等文献的考察,可以发现周代大夫以上社会阶层婚娶的时间基本上可以确定集中在夏历的仲秋至仲春之间,而士庶阶层的婚娶集中在夏历仲春之时。如果把郑玄与《毛传》之说指向不同的社会阶层,这两种观点都为有据,从而可以正确解读《诗经》中有关婚娶的诗歌,加深对周代礼制的认识。 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.
《Structural equation modeling》2013,20(1):142-148
Confirmatory factor analysis (CFA) is a statistical procedure frequently used to test the fit of data to measurement models. Published CFA studies typically report factor pattern coefficients. Few reports, however, also present factor structure coefficients, which can be essential for the accurate interpretation of CFA results. The interpretation errors that can arise when CFA results are interpreted without considering structure coefficients are described, and some examples from current literature illustrating these errors are also presented. 相似文献
16.
Item response theory (IRT) methods are generally used to create score scales for large-scale tests. Research has shown that IRT scales are stable across groups and over time. Most studies have focused on items that are dichotomously scored. Now Rasch and other IRT models are used to create scales for tests that include polytomously scored items. When tests are equated across forms, researchers check for the stability of common items before including them in equating procedures. Stability is usually examined in relation to polytomous items' central “location” on the scale without taking into account the stability of the different item scores (step difficulties). We examined the stability of score scales over a 3–5-year period, considering both stability of location values and stability of step difficulties for common item equating. We also investigated possible changes in the scale measured by the tests and systematic scale drift that might not be evident in year-to-year equating. Results across grades and content areas suggest that equating results are comparable whether or not the stability of step difficulties is taken into account. Results also suggest that there may be systematic scale drift that is not visible using year-to-year common item equating. 相似文献
17.
中国教育改革释绎的时空逻辑,是进入中国教育改革分析现场的方法论铺垫.在历史的“时间之流”中,无论“社会时间”还是“哲学的历史”,都是对历史的整体的或全面的拿捏,也是对历史演进中变与不变因素的把捉.在解释的“空间格局”中,无论教育还是教育改革,都是社会的日常生活,并对社会主体、社会生活产生深刻而巨大的意义;日常生活决不意味着必须仅在一定时空中,而是包括教育改革在内的日常生活,只有在空间与时间中才会具体而现实. 相似文献
18.
陈晓春 《四川师范大学学报(社会科学版)》2006,33(2):64-70
郭沫若一生崇儒,他对儒家文化精神进行了创造性的阐释,确立了原儒的基本精神为“动”的精神。从五四到抗战,郭沫若根据时代的需要,围绕儒家“动”的文化精神对儒家文化进行了更为具体的阐释,其阐释体现了从审美解读到民族精神建构的轨迹。 相似文献
19.
我国学界对法律关系理论十分热衷,尤其是主体问题的探讨经久不衰,但是对客体和内容范畴的问题进行的研究却十分有限。文章立足于法律关系理论,围绕法律关系三要素中的内容为中心,探讨政府环境权利与环境义务。通过考据和释义,阐明了政府权力与权利的联系和区别,进而论述了政府环境权利与环境义务的关系。 相似文献
20.
高年级小学生社会信息加工特点研究 总被引：7，自引：0，他引：7
社会认知研究范式的主要特点是采用信息加工过程模式来理解社会心理现象.通过这种模式考察儿童社会信息加工各阶段的特点有助于揭示社会性发展的内部机制.51名高年级小学生参加了结构性访谈,结果表明,在模糊同伴情景下,编码、解释、人际效能感以及反应执行水平上存在显著年级差异;男孩产生的反应数量显著多于女孩,男孩的侵犯性反应多于女孩.模糊权威情景下,编码和解释水平上存在显著年级差异;男女无差异.在清晰权威情景下,反应执行水平上存在显著年级差异;男女儿童对社会线索的解释也有显著差异. 相似文献