Modeling slow decisions: Validation of the Diffusion Model for a new type of tasks

• Applicant: Professor Dr. Andreas Voß
• Subject Area: General, Cognitive and Mathematical Psychology
• Term: from 2012 to 2016
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 218833259

This project investigates the possibility to use stochastic diffusion models for the analysis of reaction time data from tasks with response latencies of several seconds. Diffusion models allow disentangling cognitive processes from binary decision tasks by mapping these on distinct parameters. The model provides, among other, valid measures of the rate of information accumulation, the individual response threshold, and the duration of encoding and response execution. Thus, this form of data analysis allows a detailed understanding of cognitive decision-making processes. Until now, fast decisions (of several hundred milliseconds), were considered a prerequisite for diffusion model analyses. However, such fast classification tasks have a low ecological validity for everyday decisions. We argue that the diffusion model is also suitable for tasks with longer phases of information accumulation or processing. Since the cognitive processes in such slower tasks are more typical for decision-making in everyday life, we expect a better criterion validity of the model parameters. In this project, first the validity of the diffusion model is tested for various experimental paradigms with moderate to high response latencies (Work Package 1). Then we investigate whether the drift parameter of the model, which reflects the rate of information accumulation, can be used as a diagnostic measure of intelligence (Work Package 2), and whether the threshold parameter can be used as a measure of impulsive decision-making behavior (Work Package 3).

• DFG Programme: Research Grants