find_beta_parms: Find parameters for Beta prior based on prior mean and one...

In bayesics: Bayesian Analyses for One- and Two-Sample Inference and Regression Methods

Find parameters for Beta prior based on prior mean and one quantile

Description

Find parameters for Beta prior based on prior mean and one quantile

Usage

find_beta_parms(
  mean,
  quantile,
  left_tail_prob,
  plot_results = TRUE,
  search_bounds = c(0.001, 100)
)

Arguments

mean	numeric between 0 and 1 giving the prior mean
quantile	numeric between 0 and 1 giving the quantile lying at left_tail_prob
left_tail_prob	numeric between 0 and 1 giving the prior probability of theta being less than or equal to quantile
plot_results	logical. Should the resulting inverse gamma distribution be plotted?
search_bounds	bounds with which to search. Sometimes you need to adjust this to get a good solution.

Value

Vector of beta shape parameters

Examples

find_beta_parms(2/5,0.68,0.9)
2/ (2 + 3)
qbeta(0.9,2,3)

bayesics documentation built on March 11, 2026, 5:07 p.m.