Abstract
In the present article, a flexible and fast computer program, calledfast-dm, for diffusion model data analysis is introduced. Fast-dm is free software that can be downloaded from the authors’ websites. The program allows estimating all parameters of Ratcliff ’s (1978) diffusion model from the empirical response time distributions of any binary classification task. Fast-dm is easy to use: it reads input data from simple text files, while program settings are specified by command0s in a control file. With fast-dm, complex models can be fitted, where some parameters may vary between experimental conditions, while other parameters are constrained to be equal across conditions. Detailed directions for use of fast-dm are presented, as well as results from three short simulation studies exemplifying the utility of fast-dm.
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The research reported in this article was supported by Grant Kl 614/31-1 from the Deutsche Forschungsgemeinschaft to Karl Christoph Klauer.
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Voss, A., Voss, J. Fast-dm: A free program for efficient diffusion model analysis. Behavior Research Methods 39, 767–775 (2007). https://doi.org/10.3758/BF03192967
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DOI: https://doi.org/10.3758/BF03192967