What does the item response theory measure?
The item response theory (IRT), also known as the latent response theory refers to a family of mathematical models that attempt to explain the relationship between latent traits (unobservable characteristic or attribute) and their manifestations (i.e. observed outcomes, responses or performance).
What is Rasch measurement theory?
The Rasch model is used to measure latent traits like attitude or ability; It shows the probability of an individual getting a correct response on a test item. The Rasch model is a lot simpler and intuitive than many other models.
What is item response theory in educational assessment?
Item response theory (IRT) was first proposed in the field of psychometrics for the purpose of ability assessment. It is widely used in education to calibrate and evaluate items in tests, questionnaires, and other instruments and to score subjects on their abilities, attitudes, or other latent traits.
What is item analysis and how it can be done?
Item analysis is a process which examines student responses to individual test items (questions) in order to assess the quality of those items and of the test as a whole.
What are the three characteristics of an item response theory curve?
There are three main assumptions for IRT. They are: (1) dimensionality of the latent space, (2) local independence of items, and (3) item characteristic curves. Each of these will be described.
What are Rasch scores?
Rasch analysis is a statistical procedure within IRT that calculates item difficulty in relation to personal ability and weights the overall scores accordingly. The resulting scores are on a linear scale, allowing easy comparison of measures and easy interpretation of changes in scores.
What is Rasch UnIT?
RIT stands for Rasch UnIT and is a measurement scale developed to simplify the interpretation of test scores. It is an equal-interval scale, like feet and inches on a ruler, so scores can be added together to calculate accurate class or school averages.
What is the advantage of item response theory?
The use of IRT with test development has several advantages over CTT mainly because IRT produces person parameter invariance (test scores are not dependent on the particular choice of test items) when model fit is present, and test information functions provide the amount of information or “measurement precision” …
Why is item analysis important in assessment?
Item analyses are intended to assess and improve the reliability of your tests. If test reliability is low, test validity will necessarily also be low. This is the ultimate reason you do item analyses—to improve the validity of a test by improving its reliability.
What are the assumptions of item response theory?
6 Key IRT Assumptions. Several key assumptions underlie the IRT framework, including (i) unidimensionality of the measured trait, (ii) local independence, (iii) monotonicity, and (iv) item invariance. Unidimensionality assumes that a set of items on a scale measure just one thing in common.
What is the Rasch model for measurement?
Rasch models for measurement. Series: quantitative applications in the social sciences. London: Sage Publications. This short book reviews the general principles underlying the Rasch Model and focuses on the simple logistic model for dichotomous data. Concepts are solidified through use of one example throughout the text.
What is Item Response Theory in psychology?
Item Response Theory (also known as Modern Test Theory) is a mathematical approach for quantifying latent traits based on the fundamental assumption that a subject’s response to an item is a function of the difference between 1) his/her abilities and 2) the characteristics of the item.
How similar are the difficulty and discrimination parameters from the Rasch model?
The estimated difficulty parameters (Dffclt) seem roughly comparable to those from the Rasch model. The discrimination parameters (Dscrmn), which were all equal in the Rasch model, show some but not massive heterogeneity. This is also evident from the plot of the ICCs. Note that res_2pl_1 and res_rm_1 were estimated using two different packages.
What are the best books on Rasch measurement theory?
Andrich, David, and Ida Marais. A Course in Rasch Measurement Theory: Measuring in the Educational, Social and Health Sciences. Singapore: Springer, 2019. Bond, Trevor G., Zi Yan, and Moritz Heene. Applying the Rasch Model: Fundamental Measurement in the Human Sciences (4th Ed.).