An introduction to the Item Response Warehouse (IRW): A resource for enhancing data usage in psychometrics

The Item Response Warehouse (IRW) is a collection and standardization of a large volume of item response datasets in a free and open-source platform for researchers. We describe key elements of the data standardization process and provide a brief description of the over 900 datasets in the current iteration of the IRW (version 28.2). We describe how to access the data through both the website and an API, and offer a brief tutorial with example R code illustrating how to download data from the IRW and use it in standard psychometric analyses. While we are continuing to develop the IRW, this presentation may help researchers utilize data from this resource for work in psychometrics and related fields.