Systems factorial technology with R.

Systems factorial technology (SFT) comprises a set of powerful nonparametric models and measures, together with a theory-driven experiment methodology termed the double factorial paradigm (DFP), for assessing the cognitive information-processing mechanisms supporting the processing of multiple sources of information in a given task (Townsend and Nozawa, Journal of Mathematical Psychology 39:321-360, 1995). We provide an overview of the model-based measures of SFT, together with a tutorial on designing a DFP experiment to take advantage of all SFT measures in a single experiment. Illustrative examples are given to highlight the breadth of applicability of these techniques across psychology. We further introduce and demonstrate a new package for performing SFT analyses using R for statistical computing.