Code, data and materials for the manuscript "Apathy is associated with reduced precision of prior beliefs about action outcomes", published in *Journal of Experimental Psychology: General* [(link to article)](http://dx.doi.org/10.1037/xge0000739). This repository is organised as follows: * analysis.R is the main analysis script that reproduces the results and figures from the manuscript. * data contains the (de-identified) raw data file, pinball_full.txt. * experiment contains the Matlab code used to run the experiment. * pinballR is an R package of functions that reproduce specific results or figures, in support of the main analysis script. Note that these functions are deliberately inflexible and probably would not make sense outside of the context of the current project - the emphasis is on reproducibility. * platenotation contains LaTeX code to reproduce figure 5A and supplementary figure 1. * bayesFit.stan, bayesFit_obsprior.stan and bayesFit_shift.stan are the Stan code files corresponding to the Bayesian models. We call on these files in the analysis.R script to fit the models via R. * output and figs are empty folders that will be filled up by running the analysis.R script. ---------- The experiment was programmed and run in Matlab R2014a on a Windows 7 machine, using the [Psychtoolbox extensions](http://psychtoolbox.org/) (version 3.0.13). The analysis code was written in [R](https://www.r-project.org/) (version 3.5.0); additional R packages needed to run the analyses are installed and loaded in the main analysis script (analysis.R). Note that all code is provided "as is", without warranty of any kind. ---------- For any questions regarding this repository, please contact the corresponding author, Frank H. Hezemans: <Frank.Hezemans@mrc-cbu.cam.ac.uk>. If you use this repository's code or materials in your own research, please cite the corresponding journal article: Hezemans, F. H., Wolpe, N., & Rowe, J. B. (2020). Apathy is associated with reduced precision of prior beliefs about action outcomes. *Journal of Experimental Psychology: General*. Advance online publication. http://dx.doi.org/10.1037/xge0000739