IRTtool.com is a webinterface for the cran package ltm by Dimitris Rizopoulos. It is an attempt to make IRT modeling easier available for applied researchers. The application supports 1 parameter (Rasch), 2 parameter and 3 parameter IRT modeling. Other options include importing and exporting data, plotting information curves and exporting to PDF.
What it does
The user has to upload a datafile, which can be either in SPSS (.sav) or Comma Separated (.csv) format. A list of variables in the datafile is then displayed, and the user has to select which variables are to be added to the model, and the type of IRT model (1p, 2p or 3p). When the fitting of the model has been successful, parameters are displayed, and options appear to call up graphs, information, or a PDF report.
The application is publicly available at http://vps.jeroenooms.com/irttool/