The full manual of EL Version .0 User’s guide (pdf/Word files of 34 pages) is available.  The source codes written in Fortran90 (a self-decompressing file) will be obtained upon request to the author by e-mail.  It is convenient to decompress the file in a special file folder since you will have 10 files.  The following are the contents of the manual.




EL Version 1.0 User’s guide


A set of subroutines for the methods of item response theory (IRT)

Equating/Linking with their asymptotic standard errors



Haruhiko Ogasawara

May, 2003


© H. Ogasawara

Otaru University of Commerce, 3-5-21 Midori, Otaru 047-8501 Japan




1. General notes


2. Item parameter estimation

2.1 NRM1: Generation of quadrature points

2.2 ELPEV1: Item parameter estimation by the marginal maximum likelihood method


3. ELV1: IRT equating and linking with their asymptotic standard errors


4. An example

4.1 Data

4.2 Usage

4.3 Results


Appendix 1. Technical subroutines

Appendix 2. An example of extended problem size