Item Response Theory

A 2-Day Seminar Taught by Tenko Raykov, Ph.D. 

Behavioral, social, educational, biomedical, business, and marketing scientists are frequently involved in the evaluation, development and revision of multiple-component measuring instruments, such as tests, scales, inventories, questionnaires, surveys, self-reports, testlets, subscales, etc. Scores obtained from them are often employed in various analyses addressing substantive research questions. The quality of these instruments and resulting individual parameter estimates determine the extent to which the subsequent analyses and modeling efforts can be trusted. To ensure high quality of the measuring instruments, researchers must carefully study their psychometric properties and engage in possibly multiple revisions of them.

This two-day seminar provides a thorough introduction to Item Response Theory (IRT, Item Response Modeling, IRM), and covers also multiple intermediate level as well as several more advanced topics. Throughout the seminar, numerous empirical examples are utilized from the educational, behavioral, and social sciences. The popular packages Stata and Mplus are used in the examples, along with a detailed discussion of the needed command syntax and interpretation of the resulting output. References to the increasingly popular software flexMIRT are made on several occasions as well as to IRTPRO and the package ‘ltm’ of R, and use of them is made in some of the examples. At the end of the seminar, the participants will also be able to conduct software-based analyses using the modeling methods covered in the course.

Participants in this seminar can expect to come away with:

  1. A nuanced understanding of the conceptual foundations and basic mathematical and statistical relationships underlying IRT/IRM.
  2. The ability to understand, interpret and explain the output from Stata and Mplus when used for IRT/IRM, and to evaluate pertinent psychometric properties of given measuring instruments, such as tests, scales, testlets, subscales, inventories, self-reports, surveys or questionnaires.
  3.  An appreciation of the advantages of a thorough study of the underlying latent structure of (tentative versions of) multi-component instruments.
  4. Practical tools and strategies for constructing an initial version of a test/instrument of interest and its revision aimed at improving its quality, based on item information and test information functions.
  5. The ability to improve a given measuring instrument, in order to achieve corresponding higher psychometric standards.
  6. The ability to deal with issues arising in the practice of studying tests, scales, and behavioral or mental measuring instruments using IRT/IRM.


This seminar will use predominantly Stata and Mplus for the examples, but prior knowledge or familiarity with these software packages is not required. Although it is not essential, you are welcome to bring your own laptop computer, and outlets will be provided at each seat. 


To benefit from this seminar, you should have the equivalent of one or more semesters of statistics: a good introductory course with some treatment of probability and random variables as well as regression analysis. Some knowledge of multivariate statistics would also be helpful, but is not essential.


The seminar meets Friday, November 4 and Saturday, November 5 at Temple University Center City, 1515 Market Street, Philadelphia, PA 19103. The class will meet from 9 to 4 each day with a 1-hour lunch break. 

Participants receive a bound manual containing detailed lecture notes (with equations and graphics), all data sets used in the workshop, as well as examples of computer output and many other useful features. This book frees participants from the distracting task of note taking. 


The fee of $995 includes all course materials.

Lodging Reservation Instructions

A block of guest rooms has been reserved at the Club Quarters Hotel, 1628 Chestnut Street, Philadelphia, PA at a special rate of $149 per night. This location is about a 5 minute walk to the seminar location. In order to make reservations, call 203-905-2100 during business hours and identify yourself by using group code STA003 or click here. For guaranteed rate and availability, you must reserve your room no later than October 2, 2016.

If you make reservations after the cut-off date ask for the Statistical Horizon’s room rate (do not use the code) and they will try to accommodate your request.


  1. Resources for the course.
  2. Introduction, brief history, and a short overview of Item Response Theory (IRT)/Item Response Modeling (IRM).
  3. A start-up example.
  4. Popular unidimensional IRT models.
  5. Parameter estimation in item response models.
  6. Item information and test information functions. Test characteristic curves.
  7. Measuring instrument construction, development, and revision using IRT/IRM
  8. Differential item functioning and methods for its examination. 
  9. Polytomous IRT models.
  10. Multidimensional IRT/IRM.
  11. Extensions and limitations of contemporary IRT/IRM applications. 
  12. Conclusion and outlook.