Chimpanzees rationally revise their beliefs

The selective revision of beliefs in light of new evidence has been considered one of the hallmarks of human-level rationality. However, tests of this ability in other species are lacking. We examined whether and how chimpanzees (Pan troglodytes) update their initial belief about the location of a reward in response to conflicting evidence. Chimpanzees responded to counter-evidence in ways predicted by a formal model of rational belief revision: they remained committed to their initial belief when the evidence supporting the alternative belief was weaker, but they revised their initial belief when the supporting evidence was stronger. Results suggest that this pattern of belief revision was guided by the explicit representation and weighing of evidence. Taken together, these findings indicate that chimpanzees metacognitively evaluate conflicting pieces of evidence within a reflective process. , , ## Chimpanzees Rationally Revise Their Beliefs

This repository contains data, code, and output for the paper \"Chimpanzees Rationally Revise Their Beliefs,\" published in Science.

For questions or comments, please contact Emily M. Sanford at [[e-mail]](mailto:[e-mail]).

## Analysis Files

* \[`All_Analyses.Rmd`]: Contains all analyses for all experiments.
* The first chunk in the file specifies the packages that must be installed in R to run the script.
* To run the full analysis, you will need to download [`Functions.zip`] and place the unzipped folder in your working directory.
* You must also download [`Stan_Models.zip`] and place the unzipped folder in your working directory to fit the Bayesian computational models.
* \[`R_Data_Part_1.RData`] and [`R_Data_Part_2.RData`]: These two files contain the results of running the [`All_Analyses.Rmd`] file, which is time consuming to run. These objects can be loaded in the first chunk of [`All_Analyses.Rmd`] t..., ,