Houghton mifflin textbook explanation of itemresponse theory. Then they store them like little chunks of code that they can plug and play into other progra. Item response theory irt has become a popular methodological framework for modeling response data from assessments in education and health. Sep 05, 20 this book develops an intuitive understanding of irt principles through the use of graphical displays and analogies to familiar psychological principles. Item response theory irt, also called latent trait theory, is a psychometric theory that was created to better understand how individuals respond to individual items on psychological and educational tests. Item response theory irt has its roots in thurstones work to scale tests of mental development in the 1920s. Perhaps it is because irt is not a single statistical model, but a family of increasing complex models and estimation techniques. Item response theory wikipedia, the free encyclopedia. It is not the only modern test theory, but it is the most popular one and is currently an area of active research. Item response theory irt, also known as latent trait theory or modern mental test theory.
Item response theory or irt is a theory in psychometrics that is based on the assumption that individual answers or responses to questions have actual mathematical relationships. The underlying theory is built around a series of mathematical formulas that have parameters that need to be estimated using complex statistical algorithms. As discussed by bock, thurstone envisioned a measurement model in which the probability of success on a given intelligence test item was a function of the chronological age of the respondent. Two introductory books are suggested to students and professors interested in irt for. Item bias is generally defined as conditional dependence. Each item in a test will have its own item characteristic curve. To examine the assumptions of the item response theory and to define the item parameters, we need largescale sample cases hambleton, 1990. Understanding item analyses 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.
Among the greatest advantages of the item response theory over the classic measurement theory are. Lords book, applications of item response theory to practical testing problems, presented much of the current irt theory in language easily understood by many practitioners. Using r for item response theory model applications 1st. It covered basic concepts, comparison to ctt methods, relative efficiency, optimal number of choices per item, flexilevel tests, multistage tests, tailored testing. As a result of a comprehensive survey of the related literature, the author provides nuggets of information about a wide range of rules of thumb and analysis alternatives. In item response theory, it is known as the item characteristic curve. Designed for researchers, psychometric professionals, and advanced students, this book clearly presents both the howto and the why of irt. Introduction to educational and psychological measurement using r. In psychometrics, item response theory is a paradigm for the design, analysis, and scoring of tests, questionnaires, and similar instruments measuring abilities, attitudes, or other variables. The mathematical theory underlying rasch models is a special case of item response theory and, more generally, a special case of a generalized linear model. While now 50 years old assuming the birth is the classic lord and novick 1969 text it is still underutilized and remains a mystery to many practitioners. This application is due in large part to gains in the precision of measurement attributable to item response theory and corresponding decreases in response burden, study costs, and study duration.
This book describes various item response theory models and furnishes detailed explanations of algorithms that can be used to estimate the item and ability parameters. A course in item response theory and modeling with stata, by tenko raykov and george a. However, there are important differences in the interpretation of the model parameters and its philosophical implications 5 that separate proponents of the rasch model from the item. Therefore, considerable attention will be devoted to this curve and its role. Book description item response theory irt is widely used in education and psychology and is expanding its applications to other social science areas, medical research, and business as well. How would you explain irt item response theory to a. Latent structure analysis is here defined as a mathematical model for. Item response theory christine demars oxford university press. Item response theory aka irt is also sometimes called latent trait theory. I recently received a email from a researcher that wanted to implement item response theory, but was not sure where to start. It occurred to me that there are plenty of resources out there which describe irt but few, if any, that provide guidance for how someone new to the topic could apply irt. Item response theory irt represents an important innovation in the field of psychometrics. Item response theoryirt is a way to analyze responses to tests or questionnaires with the goal of improving measurement accuracy and. Introduction to educational and psychological measurement.
The theory and practice of item response theory methodology. The central feature of irt models is that they relate item responses to characteristics of individual persons and assessment items. Instead of assuming all questions contribute equivalently to our understanding of a students abilities, irt provides a mo. Multidimensional item response theory springerlink. A typical item characteristic curve the item characteristic curve is the basic building block of item response theory. Item response theory irt is arguably one of the most influential developments in the field of educational and psychological measurement. Item response theory irt model differs in terms of the number of parameters contained in the model. His work with the ets had impacts on the law school admissions test, the test of english as a foreign language, and the graduate record exam. For detecting biased items, statistical tests and indices based on item response theory have been proposed.
The book describes the commonly used multidimensional item response theory mirt models and the important methods needed for their practical application. Multidimensional item response theory is the first book to give thorough coverage to this emerging area of psychometrics. Houghton mifflin textbook explanation of itemresponse. One could make a case that item response theory is the most important statistical method about which most of us know little or nothing. 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. A course in item response theory and modeling with stata. Apr 18, 2016 item response theory irt has become a popular methodological framework for modeling response data from assessments in education and health. This is a title in our understanding statistics series, which is designed to provide researchers with authoritative guides to understanding, presenting and critiquing analyses and associated inferences. Through irt, the abilities or intelligence of people are said to be measurable through various mathematical models and techniques. Individual test items are important in both irt and classical psychometric theory, but irt and classical.
Item response theory irt comprises a set of generalized latent variable models designed specifically for data arising from educational and psychological tests and questionnaires. Its a theory of measurement, more precisely a psychometric theory. Irt provides a foundation for statistical methods that are utilized in contexts such as test development, item analysis, equating, item banking, and computerized adaptive testing. Irt as a family of statistical models, particularly. It is based on the application of related mathematical models to testing data. As its name implies, the characteristics of individual test items are at the heart of the theory. Novick on test theory, which was an expansion of his dissertation. Measuring web usability using item response theory.
A brief explanation of itemresponse theory 1 conceptual background itemresponse theory irt offers a different way to construct tests. Since we have not been able to meet this requirement. From this point of view, item response theory irt is a powerful tool that enables the construction of standardised scales from a set of items via mathematical models embretson and reise, 2000. Polytomous irt models are given central coverage since many psychological tests use rating scales. Item response theory irt has become a popular methodological. An items response categories can be assessed by analyzing the item response curves, which is produced descriptively in classical test theory by plotting the percentage of subjects choosing each response option on the yaxis and the total score, expressed as such or percentiles or other metric, on the xaxis.
It is used for statistical analysis and development of assessments, often for high. Item response theory irt comprises a set of generalized latent variable. This book provides a thorough overview of item response theory methodology, with a nice blend of theoretical psychometrics and practical applications. Item response theory irt is a latent variable modeling approach used to minimize bias and optimize the measurement power of educational and psychological tests and other psychometric applications. Meaning, interpretations, and measurementscale properties. In the context of usability, schmettow and vietze 2008 discuss the use of irt in measuring usability inspection processes. The foundation of irt is a mathematical model defined by item. Jan 23, 2014 item response theory or irt is a theory in psychometrics that is based on the assumption that individual answers or responses to questions have actual mathematical relationships. This is a modern test theory as opposed to classical test theory. Baker, item response theory can evaluate a same scala the items and examenees and it allow that the measurement made with irt are invariant respect to the item on a test used on the medition.
Several different statistical models are used to represent both item and test taker charact. Lords book, applications of item response theory to practical testing. In psychometrics, item response theory irt is a paradigm for the design, analysis, and scoring. It is widely used in education to calibrate and evaluate items in tests, questionnaires, and other. The theory and practice of item response theory rafael. Item analysis is especially valuable in improving items which will be used again in later tests, but it can also be used to eliminate ambiguous or. In psychometrics, the theory has been superseded by the more sophisticated models in item response theory irt and generalizability theory g theory.
An introduction to item response theory and rasch analysis. An application of item response theory to psychological. The first edition is available as free on line book chapters available. Understanding item analyses office of educational assessment.
Nov 30, 2014 in psychometrics, item response theory irt also known as latent trait theory, strong true score theory, or modern mental test theory, is a paradigm for the design, analysis, and scoring of tests. Demars in her book chapter classical test theory and item response theory still uses axioms based on the basic ctt equation to derive the most common formulas used in ctt. In psychometrics, item response theory irt also known as latent trait theory, strong true score theory, or modern mental test theory, is a paradigm for the design, analysis, and scoring of tests. It surveys contemporary irt models, estimation methods, and computer programs. Item response theory irt model differs in terms of the number of. 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.
Irt was applied to two scales a positive and a negative affect. That is, plenty of resources that define the abc parameters and discuss the item response. Marcoulides, is a comprehensive introduction to the concepts of irt that includes numerous examples using statas powerful suite of irt commands. Jan 01, 2009 item response theory irt is a latent variable modeling approach used to minimize bias and optimize the measurement power of educational and psychological tests and other psychometric applications. Classical test theory is an influential theory of test scores in the social sciences. Item response theory models student ability using question level performance instead of aggregate test level performance. Item response theory each individual item can be used for comparison purposes person endorses better rating on hard itemsthe person is higher on the trait person endorses worse rating on easy items the person is lower on the trait items that measure the. Sep 10, 2012 this sounds like it belongs in a selfhelp book. Item response theory each individual item can be used for comparison purposes person endorses better rating on hard itemsthe person is higher on the trait person endorses worse rating on easy items the person is lower on the trait items that measure the same construct can be aggregated into longer assessments.
Chapter 8 the new psychometrics item response theory. Item response theory irt is arguably one of the most in. The item characteristic curve is the basic building block of item response theory. In psychometrics, item response theory irt also known as latent trait theory, strong true score theory, or modern mental test theory, is a paradigm for the design, analysis, and scoring of tests, questionnaires, and similar instruments measuring abilities, attitudes, or other variables. These three books item response theory principles and applications, item response. An application of item response theory to psychological test. Thus, the use of multidimensional item response theory in composite score creation may provide better composite estimates. Smart folks analyze the quality of questions, determining how appropriate they are for given respondents and the quality of answers they seem to provide. Although demars irt can be considered to be an introductory book and requires almost no mathstats background it covers a variety of topics about item response theory. A brief explanation of item response theory 1 conceptual background item response theory irt offers a different way to construct tests. This paper aims to provide a didactic application of irt and to highlight some of these advantages for psychological test development.
Item response theory irt you will know about some of the potential applications you will be aware of some of the limitations of the approach you will be aware of which software packages are irtcapable you will think about potential opportunities in your own work to apply irt. This book develops an intuitive understanding of irt principles through the use of graphical displays and analogies to familiar psychological principles. Later, hambleton and swaminathan 1985 produced a comprehensive textbook on irt. It is a theory of testing based on the relationship between individuals performances on a test item and the test takers levels of performance on an overall measure of the ability that item was designed to measure. An introduction to item response theory and rasch analysis of. In many achievementtesting situations it is useful or sometime required to.
Overview of classical test theory and item response theory. Many books have been written that address item response theory or contain irt or irtlike models. Whereas classical test theory focuses on the test as a whole, item response theory shifts its focus to the individual items questions themselves. Item response theory irt is arguably one of the most influential developments in the field of. Each is an attempt to explain the process by which individuals respond to. In psychometrics, the theory has been superseded by the more sophisticated models in item response theory irt and generalizability theory gtheory. Item response theory has its origins in educational measurement and is now commonly applied in healthrelated measurement of latent traits, such as function and symptoms.
1524 19 1400 742 84 843 1212 280 1120 357 751 774 306 972 1106 191 819 136 1659 660 539 974 31 712 1239 253 696 1679 822 355 312 248 1012 1679 1330 709 270 923 294 21 304 1264