Abstract
The EZ-diffusion model for two-choice response time tasks takes mean response time, the variance of response time, and response accuracy as inputs. The model transforms these data via three simple equations to produce unique values for the quality of information, response conservativeness, and nondecision time. This transformation of observed data in terms of unobserved variables addresses the speed—accuracy trade-off and allows an unambiguous quantification of performance differences in two-choice response time tasks. The EZ-diffusion model can be applied to data-sparse situations to facilitate individual subject analysis. We studied the performance of the EZ-diffusion model in terms of parameter recovery and robustness against misspecification by using Monte Carlo simulations. The EZ model was also applied to a real-world data set.
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This research was funded by a VENI grant from the Dutch Organization for Scientific Research (NWO). Part of this work was presented at the 4th Annual Summer Interdisciplinary Conference, Briançon, France (July 2005), and at the 38th Annual Meeting of the Society for Mathematical Psychology, Memphis, Tennessee (August 2005).
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Wagenmakers, EJ., Van Der Maas, H.L.J. & Grasman, R.P.P.P. An EZ-diffusion model for response time and accuracy. Psychonomic Bulletin & Review 14, 3–22 (2007). https://doi.org/10.3758/BF03194023
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DOI: https://doi.org/10.3758/BF03194023