HomepageIRT (Item Response Theory) has been undergoing
important developments in the past few years. Indeed, many general
purpose statistical packages still don't have procedures
implementing these new indices, methods and models. As a consequence, a significant number of
specific packages have been developed by psychometricians (see
http://www.assess.com).
However, no package offers a comprehensive set of methods, and no
package has emerged as standard tool in the field. The increasing sophistication of general
statistical packages, on the other hand, allows user-written
routines to be developed which will implement IRT methods within the
context of an already-familiar computing environment. This site presents a set of macro-programs for
use with Stata or SAS. While they were originally developed to
analyse quality of life scales, they can, of course, be used in the
area of psychometrics, test construction etc. These macros come in the following categories:
- Selection of items to form unidimensional scales (RASCHFIT, MSP, HCACCPROX, BACKRASCH, CLV)
- Validation of a supposed structure of the items (DETECT, LOEVH)
- Traces of the items (ANAQOL, TRACES)
- Modelling (ANAQOL, GEEKEL2D, RASCHTEST, MMSRM)
- Graphical validation (ANAQOL,RASCHTEST)
- Tests for the Rasch model (ANAQOL, RASCHTEST)
- Simulation of data (SIMIRT)
- Others tools (GAMMASYM, GAUSSHERMITE)
The spirit of this web site inspired the creation
of the FreeIRT
Project in collaboration with Karl Bang Christensen. |
