beta.select {LearnBayes} | R Documentation |
Finds the shape parameters of a beta density that matches knowledge of two quantiles of the distribution.
beta.select(quantile1, quantile2)
quantile1 |
list with components p, the value of the first probability, and x, the value of the first quantile |
quantile2 |
list with components p, the value of the second probability, and x, the value of the second quantile |
vector of shape parameters of the matching beta distribution
Jim Albert
# person believes the median of the prior is 0.25
# and the 90th percentile of the prior is 0.45
quantile1=list(p=.5,x=0.25)
quantile2=list(p=.9,x=0.45)
beta.select(quantile1,quantile2)