Cognitivemodels – an Extendable R Software Package to Develop and Test Cognitive Models

We present the software package cognitivemodels, a tool to build, apply, estimate, test, and develop computational cognitive models in R. The free package is designed for coding efficiency, robustness, and flexibility and offers novice modelers a user-friendly front-end to use models and experienced modelers a powerful back-end to write models. Here, we show how the package implements the generalized context model (Nosofsky, 1986) and cumulative prospect theory (Tversky \& Kahneman, 1992) and how end users can write further models with the package. We further present the package's variety of goodness-of-fit measures (e.g., binomial or normal log likelihood, mean-squared error, or accuracy), parameter constraints (linear constraints, box constraints, equality constraints, fixed parameters), optimization routines (e.g., Nelder-Mead), and choice rules (e.g., soft-max, epsilon greedy, or Luce's choice rule). We believe the package makes cognitive modeling more widely accessible and adds to robust model development.