This archive presents codes and functions in R programming language that were used in "Using informative priors to better quantify the occurrence rate of a rare tree-related microhabitat locally" by P. Cottais et al. (doi : 10.1101/2024.11.28.625900). The archive is made of seven files : is a commented R source file that contains all the functions and library imports used in the study; Main.rmd is a RMarkdown file that presents the global pipeline of analyses used in the study of P. Cottais et al.; Main.pdf is a compiled version of Main.rmd in a more readable pdf format; ggplots.R is a R source file containing functions to generate some graphical outputs, it is called by Main.rmd; chains_process.R is a R source file containing custom-made functions to handle MCMC outputs , it is called by Main.rmd; Weibull_Hierarchic_11A_Rot.Hole_Chains.txt is a text file containing the MCMC output of Courbaud et al (2022) continental model, used in building informative priors in the study of P. Cottais et al. , , it is read by Main.rmd; model_nonInfo.r is a R source file creating functions to run bayesian estimation with non informative priors; model_Info.r is a R source file creating functions to run bayesian estimation with informative priors.