Dear Colleagues, PriorGen is an R package that generates priors in the form of beta and Gamma distributions got proportions. You may find it useful for the generation of priors on the sensitivity/specificity of diagnostic tests and the prevalence of disease.
The findbeta function estimates the parameters of a Beta distribution based on the existing prior beliefs about the mean (or the median or the mode) and whether it is lower or greater that a certain value with a pre-specified certainty (usually set at 95%). The findbetaqq function estimates the parameters of a Beta distribution based on the existing prior beliefs about the values of two distinct percentiles. The findbetamupsi function estimates: 1. the parameters of a Beta distribution for the expected mean of a proportion -usually the prevalence of disease/infection. 2. the parameters of a Gamma distribution expressing our prior belief about the variability (ψ) of the prevalence estimates across the units of the area/region under consideration. You may download it from here: https://cran.r-project.org/package=PriorGen Hope you find it helpful and, of course, any comments/suggestions are most welcome. Polychronis To cite package ‘PriorGen’ in publications use: Polychronis Kostoulas (2018). PriorGen: Generates Prior Distributions for Proportions. R package version 1.1.2. https://CRAN.R-project.org/package=PriorGen A BibTeX entry for LaTeX users is @Manual{, title = {PriorGen: Generates Prior Distributions for Proportions}, author = {Polychronis Kostoulas}, year = {2018}, note = {R package version 1.1.2}, url = {https://CRAN.R-project.org/package=PriorGen}, } -- Polychronis P. Kostoulas D.V.M., Ph.D., Assistant Professor Associate Editor of Preventive Veterinary Medicine Erasmus+ Departmental Coordinator Laboratory of Epidemiology, Biostatistics and Animal Health Economics Faculty of Veterinary Medicine University of Thessaly Karditsa, 224 Trikalon st. GREECE. P.C. 43100 Telephone: +30 2441066022 Mobile: +30 6977881857 Email: pk...@vet.uth.gr [[alternative HTML version deleted]] _______________________________________________ R-packages mailing list R-packages@r-project.org https://stat.ethz.ch/mailman/listinfo/r-packages
