Note, difficulty refers to the number of item response functions in the items, i.e., the total number of response options minus one. In this case, 6 response options were used which means that the model has 5 levels of difficulty. # Plot RGL device on item difficulty level 5 plot(g,...
IRT理论即项目反应理论(Item Response Theory, IRT)，又称题目反应理论、潜在特质理论（Item Response Theory）是一系列心理统计学模型的总称。IRT是用来分析考试成绩或者问卷调查数据的数学模型。这些模型的目标是来确定的潜在心理特征(latent trait）是否可以通过测试题被反应出来，以及测试题和被测试者之间的互动关系。...
Item difficulty parameter appeared to be the most sensitive to fluctuations in sample size and test length; whereas, item guessing parameter appeared to be the least sensitive. On the other hand, different samples yielded comparable results in terms of accuracy in estimating the three item ...
For each item, two parameters were estimated: discrimination (a) and difficulty (b). The discrimination parameter determines the slope at which the responses to the items change as a function of the latent trait level, whereas the difficulty parameters of the item determine how much of the ...
Abstract:BycomparingCTTandIRTonhypothesis,accuracy,standarderroranditemselection,thestudyshowsIRThassev灢 eralfeaturesontheindependentitemselectionestimatingsubject’sabilityorlocation,thescaleconsistencywithitemdifficulty andability,theitemparameterestimationindependentofsample,theaccuracyofestimatingmeasurementerror.ButIRTsh...
关键词：项目反应理论；参数估计；小样本 Abstract:This paper researchs the estimation method of item response theory for small sample.First of all,this paper explores the correlation between CTT and IRT methods on the estimation results of difficulty parameters and the reasons for their formation...
8、papers, estimate the difficulty, discrimination and other parameters, get the overall effect of the test papers and students1 ability, and finally issue questionnaires for analysis.Item response theory is a measurement theory that estimates potential characteristics with item characteristic paramete 9、...
This cubes ice maker comes with an icon-based EasyTouch display that provides convenient one-touch access to important data and functions to run the machine with zero difficulty. It allows you to program the volume of ice you can produce for the day to fully maximize your supply and avoid ex...
This model assumes that the item parameters differ across groups of males and females. The difficulty parameters estimates corresponding to the female group using this fixed effects IRT model also resemble the true values. Note that the estimated standard deviations are slightly higher in comparison ...
Winsteps analyzes these data to produce an "ability", "attitude" or similar measure for every person and a difficulty measure for every question, along with many other diagnostic indicators. Facets: this is designed for situations where a person's performance on a task is rated by a rater, ...