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1.
The present paper discusses the conceptual demands of an apparently straightforward task set to secondary‐level students—completing chemical word equations with a single omitted term. Chemical equations are of considerable importance in chemistry, and school students are expected to learn to be able to write and interpret them. However, it is recognised that many students find them challenging. The present paper explores students’ accounts of their attempts to identify the missing terms, to illuminate why working with chemical word equations is so challenging from the learner’s perspective. Three hundred secondary‐age students responded to a five‐item exercise based on chemicals and types of reactions commonly met at school level. For each item they were asked to identify the missing term in a word equation, and to explain their answers. This provided a database containing more than 1,000 student accounts of their rationales. Analysis of the data led to the identification of seven main classes of strategy used to answer the questions. Most approaches required the coordination of chemical knowledge at several different levels for a successful outcome; and there was much evidence both for correct answers based on flawed chemical thinking, and appropriate chemical thinking being insufficient to lead to the correct answer. It is suggested that the model reported here should be tested by more in‐depth methods, but could help chemistry teachers appreciate learners’ difficulties and offer them explicit support in selection and application of strategies when working with chemical equations. 相似文献
2.
Dealing With Item Nonresponse in Large‐Scale Cognitive Assessments: The Impact of Missing Data Methods on Estimated Explanatory Relationships 
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下载免费PDF全文 Carmen Köhler Steffi Pohl Claus H. Carstensen 《Journal of Educational Measurement》2017,54(4):397-419
Competence data from low‐stakes educational large‐scale assessment studies allow for evaluating relationships between competencies and other variables. The impact of item‐level nonresponse has not been investigated with regard to statistics that determine the size of these relationships (e.g., correlations, regression coefficients). Classical approaches such as ignoring missing values or treating them as incorrect are currently applied in many large‐scale studies, while recent model‐based approaches that can account for nonignorable nonresponse have been developed. Estimates of item and person parameters have been demonstrated to be biased for classical approaches when missing data are missing not at random (MNAR). In our study, we focus on parameter estimates of the structural model (i.e., the true regression coefficient when regressing competence on an explanatory variable), simulating data according to various missing data mechanisms. We found that model‐based approaches and ignoring missing values performed well in retrieving regression coefficients even when we induced missing data that were MNAR. Treating missing values as incorrect responses can lead to substantial bias. We demonstrate the validity of our approach empirically and discuss the relevance of our results. 相似文献
3.
Ratings given to the same item response may have a stronger correlation than those given to different item responses, especially when raters interact with one another before giving ratings. The rater bundle model was developed to account for such local dependence by forming multiple ratings given to an item response as a bundle and assigning fixed‐effect parameters to describe response patterns in the bundle. Unfortunately, this model becomes difficult to manage when a polytomous item is graded by more than two raters. In this study, by adding random‐effect parameters to the facets model, we propose a class of generalized rater models to account for the local dependence among multiple ratings and intrarater variation in severity. A series of simulations was conducted with the freeware WinBUGS to evaluate parameter recovery of the new models and consequences of ignoring the local dependence or intrarater variation in severity. The results revealed a good parameter recovery when the data‐generating models were fit, and a poor estimation of parameters and test reliability when the local dependence or intrarater variation in severity was ignored. An empirical example is provided. 相似文献
4.
从应用的角度来思考什么是微积分,试给出微积分的一个应用模型,再根据给出的模型思考微积分在应用中的要领,从而使初学者对微积分有直观的感知. 相似文献
5.
In the presence of test speededness, the parameter estimates of item response theory models can be poorly estimated due to conditional dependencies among items, particularly for end‐of‐test items (i.e., speeded items). This article conducted a systematic comparison of five‐item calibration procedures—a two‐parameter logistic (2PL) model, a one‐dimensional mixture model, a two‐step strategy (a combination of the one‐dimensional mixture and the 2PL), a two‐dimensional mixture model, and a hybrid model‐–by examining how sample size, percentage of speeded examinees, percentage of missing responses, and way of scoring missing responses (incorrect vs. omitted) affect the item parameter estimation in speeded tests. For nonspeeded items, all five procedures showed similar results in recovering item parameters. For speeded items, the one‐dimensional mixture model, the two‐step strategy, and the two‐dimensional mixture model provided largely similar results and performed better than the 2PL model and the hybrid model in calibrating slope parameters. However, those three procedures performed similarly to the hybrid model in estimating intercept parameters. As expected, the 2PL model did not appear to be as accurate as the other models in recovering item parameters, especially when there were large numbers of examinees showing speededness and a high percentage of missing responses with incorrect scoring. Real data analysis further described the similarities and differences between the five procedures. 相似文献
6.
Wen‐Chung Wang Kuan‐Yu Jin Xue‐Lan Qiu Lei Wang 《Journal of Educational Measurement》2012,49(4):419-445
In some tests, examinees are required to choose a fixed number of items from a set of given items to answer. This practice creates a challenge to standard item response models, because more capable examinees may have an advantage by making wiser choices. In this study, we developed a new class of item response models to account for the choice effect of examinee‐selected items. The results of a series of simulation studies showed: (1) that the parameters of the new models were recovered well, (2) the parameter estimates were almost unbiased when the new models were fit to data that were simulated from standard item response models, (3) failing to consider the choice effect yielded shrunken parameter estimates for examinee‐selected items, and (4) even when the missingness mechanism in examinee‐selected items did not follow the item response functions specified in the new models, the new models still yielded a better fit than did standard item response models. An empirical example of a college entrance examination supported the use of the new models: in general, the higher the examinee's ability, the better his or her choice of items. 相似文献
7.
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
8.
Hong Jiao Akihito Kamata Shudong Wang Ying Jin 《Journal of Educational Measurement》2012,49(1):82-100
The applications of item response theory (IRT) models assume local item independence and that examinees are independent of each other. When a representative sample for psychometric analysis is selected using a cluster sampling method in a testlet‐based assessment, both local item dependence and local person dependence are likely to be induced. This study proposed a four‐level IRT model to simultaneously account for dual local dependence due to item clustering and person clustering. Model parameter estimation was explored using the Markov Chain Monte Carlo method. Model parameter recovery was evaluated in a simulation study in comparison with three other related models: the Rasch model, the Rasch testlet model, and the three‐level Rasch model for person clustering. In general, the proposed model recovered the item difficulty and person ability parameters with the least total error. The bias in both item and person parameter estimation was not affected but the standard error (SE) was affected. In some simulation conditions, the difference in classification accuracy between models could go up to 11%. The illustration using the real data generally supported model performance observed in the simulation study. 相似文献
9.
Computer‐based tests (CBTs) often use random ordering of items in order to minimize item exposure and reduce the potential for answer copying. Little research has been done, however, to examine item position effects for these tests. In this study, different versions of a Rasch model and different response time models were examined and applied to data from a CBT administration of a medical licensure examination. The models specifically were used to investigate whether item position affected item difficulty and item intensity estimates. Results indicated that the position effect was negligible. 相似文献
10.
The graded response model can be used to describe test-taking behavior when item responses are classified into ordered categories. In this study, parameter recovery in the graded response model was investigated using the MULTILOG computer program under default conditions. Based on items having five response categories, 36 simulated data sets were generated that varied on true θ distribution, true item discrimination distribution, and calibration sample size. The findings suggest, first, the correlations between the true and estimated parameters were consistently greater than 0.85 with sample sizes of at least 500. Second, the root mean square error differences between true and estimated parameters were comparable with results from binary data parameter recovery studies. Of special note was the finding that the calibration sample size had little influence on the recovery of the true ability parameter but did influence item-parameter recovery. Therefore, it appeared that item-parameter estimation error, due to small calibration samples, did not result in poor person-parameter estimation. It was concluded that at least 500 examinees are needed to achieve an adequate calibration under the graded model. 相似文献
11.
Bernard P. Veldkamp 《Journal of Educational Measurement》2016,53(2):212-228
Many standardized tests are now administered via computer rather than paper‐and‐pencil format. The computer‐based delivery mode brings with it certain advantages. One advantage is the ability to adapt the difficulty level of the test to the ability level of the test taker in what has been termed computerized adaptive testing (CAT). A second advantage is the ability to record not only the test taker's response to each item (i.e., question), but also the amount of time the test taker spends considering and answering each item. Combining these two advantages, various methods were explored for utilizing response time data in selecting appropriate items for an individual test taker. Four strategies for incorporating response time data were evaluated, and the precision of the final test‐taker score was assessed by comparing it to a benchmark value that did not take response time information into account. While differences in measurement precision and testing times were expected, results showed that the strategies did not differ much with respect to measurement precision but that there were differences with regard to the total testing time. 相似文献
12.
非参数项目反应理论模型包括单调均匀性模型和双单调模型。用单调均匀性模型对某英语听力考试结果研究发现,按照顺序选择法,可从16道听力试题中选出11道满足要求的试题,组成单维量表。用考生在这11道试题上的总得分对考生进行排序与按照潜质排序等效。利用双单调模型对11道听力试题组成的单维量表进行试题功能偏差研究发现,有5道试题在女生子群体中的排序与在男生子群体以及整个群体排序不同,显示女生子群体作出正确应答的概率明显高于男生子群体作出正确应答的概率。这种差异至少部分是由两个子群体听力能力上的差异引起的。 相似文献
13.
Response accuracy and response time data can be analyzed with a joint model to measure ability and speed of working, while accounting for relationships between item and person characteristics. In this study, person‐fit statistics are proposed for joint models to detect aberrant response accuracy and/or response time patterns. The person‐fit tests take the correlation between ability and speed into account, as well as the correlation between item characteristics. They are posited as Bayesian significance tests, which have the advantage that the extremeness of a test statistic value is quantified by a posterior probability. The person‐fit tests can be computed as by‐products of a Markov chain Monte Carlo algorithm. Simulation studies were conducted in order to evaluate their performance. For all person‐fit tests, the simulation studies showed good detection rates in identifying aberrant patterns. A real data example is given to illustrate the person‐fit statistics for the evaluation of the joint model. 相似文献
14.
Mirka Henninger 《Journal of Educational Measurement》2021,58(1):104-129
Item Response Theory models with varying thresholds are essential tools to account for unknown types of response tendencies in rating data. However, in order to separate constructs to be measured and response tendencies, specific constraints have to be imposed on varying thresholds and their interrelations. In this article, a multidimensional extension of a Partial Credit Model using a sum‐to‐zero constraint for varying thresholds is proposed. The new model allows us to flexibly account for response tendencies and to model covariations between varying thresholds that are commonly found in empirical data. The model's ability to estimate different types of response tendencies under various data structures is shown in a simulation study. An illustrative multicountry analysis demonstrates that differences between respondents in terms of their response tendencies exist and can be captured by the new model. Furthermore, it is well suited to account for extreme and mid response styles, but also to accommodate unknown, previously unmodeled, response tendencies. Therewith, the sum‐to‐zero model can be considered a suitable candidate to examine the types response tendencies in rating data and to account for biases in construct measures due to response tendencies. 相似文献
15.
Nuri Balta Víctor-Hugo Perera-Rodríguez Carlos Hervás-Gómez 《Education and Information Technologies》2018,23(2):837-850
Socrative is an online assessment and student response tool that provides opportunities to increase student engagement in the classroom. We used Socrative as an online homework completing platform to increase students’ exam scores in physics. To explore the relationships among factors and the educational effectiveness of Socrative, data from 85 undergraduate students’ final and midterm grades, and their responses to an attitude survey were used. The ANCOVA results demonstrated that the use of Socrative positively influenced students’ exam scores and a fairly significant correlation was found between students’ attitudes toward Socrative and final exam scores. Moreover, the results of the survey showed that students have moderately positive attitudes toward the use of Socrative as an online homework assignment platform. This empirical study indicates that the use of Socrative can go beyond engaging and motivating students and can be used as an online homework completing tool. 相似文献
16.
The posterior predictive model checking method is a flexible Bayesian model‐checking tool and has recently been used to assess fit of dichotomous IRT models. This paper extended previous research to polytomous IRT models. A simulation study was conducted to explore the performance of posterior predictive model checking in evaluating different aspects of fit for unidimensional graded response models. A variety of discrepancy measures (test‐level, item‐level, and pair‐wise measures) that reflected different threats to applications of graded IRT models to performance assessments were considered. Results showed that posterior predictive model checking exhibited adequate power in detecting different aspects of misfit for graded IRT models when appropriate discrepancy measures were used. Pair‐wise measures were found more powerful in detecting violations of the unidimensionality and local independence assumptions. 相似文献
17.
We present a logistic function of a monotonic polynomial with a lower asymptote, allowing additional flexibility beyond the three‐parameter logistic model. We develop a maximum marginal likelihood‐based approach to estimate the item parameters. The new item response model is demonstrated on math assessment data from a state, and a computationally efficient strategy for choosing the order of the polynomial is demonstrated. Finally, our approach is tested through simulations and compared to response function estimation using smoothed isotonic regression. Results indicate that our approach can result in small gains in item response function recovery and latent trait estimation. 相似文献
18.
伴随大数据、学习分析技术的发展,在线作业成为当前教育科技产品的重要形式,但是有关在线作业的用户体验研究并不多。文章采用技术接受模型来研究初中生和家长的在线作业用户体验及其影响因素,并结合相关研究中的教师用户体验进行比较分析,研究发现:易用性对学生和家长的在线作业使用无显著影响,对教师有影响;有用性是教师和家长更为关心的,而学生对此无感;社会影响和自我学习管理对学生和家长在线作业使用呈显著影响。基于此,文章对在线作业推广应用进行了反思,认为在线作业需避免成为强化应试的工具;教师要适应新的“把关人”角色;在线作业开发需更多地转向学生用户设计,以增强其学习体验。 相似文献
19.
Marc A. T. M. Vorstenbosch Tim P. F. M. Klaassen Jan G. M. Kooloos Sanneke M. Bolhuis Roland F. J. M. Laan 《Anatomical sciences education》2013,6(1):29-41
Anatomists often use images in assessments and examinations. This study aims to investigate the influence of different types of images on item difficulty and item discrimination in written assessments. A total of 210 of 460 students volunteered for an extra assessment in a gross anatomy course. This assessment contained 39 test items grouped in seven themes. The answer format alternated per theme and was either a labeled image or an answer list, resulting in two versions containing both images and answer lists. Subjects were randomly assigned to one version. Answer formats were compared through item scores. Both examinations had similar overall difficulty and reliability. Two cross‐sectional images resulted in greater item difficulty and item discrimination, compared to an answer list. A schematic image of fetal circulation led to decreased item difficulty and item discrimination. Three images showed variable effects. These results show that effects on assessment scores are dependent on the type of image used. Results from the two cross‐sectional images suggest an extra ability is being tested. Data from a scheme of fetal circulation suggest a cueing effect. Variable effects from other images indicate that a context‐dependent interaction takes place with the content of questions. The conclusion is that item difficulty and item discrimination can be affected when images are used instead of answer lists; thus, the use of images as a response format has potential implications for the validity of test items. Anat Sci Educ © 2012 American Association of Anatomists. 相似文献
20.
Early Identification of Student Performance and Effort Using an Online Homework System: A Pilot Study 总被引：2，自引：2，他引：0
David C. Perdian 《Journal of Science Education and Technology》2013,22(5):697-701
Two distinct student groups, in terms of academic performance, were identified early in the semester as either being under-performing students or over-performing students using an online homework system. The students who are identified as under-performing received, on average, lower grades than their fellow students but spent more time completing the homework assignments. These students are great candidates for targeted advertisement of student resources such as tutoring services. The students who are identified in the over-performing student population received higher grades than their fellow students, but spent less time completing the homework assignments. These students are great candidates for honors programs, independent research projects, and peer-tutoring programs. Incorporating these evaluation criteria to online homework systems will allow instructors to quickly identify students in these academic student populations. 相似文献