The Ratcliff diffusion model has many advantages over the traditional approach to response time analysis. Unfortunately, computational challenges have thus far prevented the model from gaining widespread use among experimental psychologists. In order to popularize the Ratcliff diffusion model, Wagenmakers, van der Maas, and Grasman (in press) developed a simplified, EZ version. The EZ-diffusion model requires no fitting, but instead simply transforms RT mean, RT variance, and percentage correct to drift rate, boundary separation, and nondecision time. This presentation will discuss the current limitations of the EZ model and how some of these limitations can be successfully addressed. |