getPrior_delta: Get prior parameters from Beta distribution

In eggCounts: Hierarchical Modelling of Faecal Egg Counts

Get prior parameters from Beta distribution

Description

Compute the shape parameters from a Beta distribution for \delta based on some prior belief.

Usage

getPrior_delta(lower, upper, p = 0.7, mode, conc, plot = TRUE)

Arguments

lower,upper,p	numeric. Prior belief about the reduction. There is p probability that the reduction is between lower and upper. Not used if mode and conc are supplied.
mode,conc	numeric. Prior belief about the reduction. The mode and concentration parameters of a beta distribution. Higher concentration indicates smaller variance. Not used if lower and upper thresholds are supplied.
plot	logical. If TRUE, the prior distribution is plotted after parameters are found.

Details

The multiroot function from rootSolve package is used to compute the parameters.

Value

Returns Beta prior parameters for \delta and the printed argument to use in a fecr_stan() or a fec_stan() function call.

Author(s)

Tea Isler
Craig Wang

Examples

# there is 80% probability that the reduction is between 60% and 90%
getPrior_delta(lower = 0.6, upper = 0.9, p = 0.8)

eggCounts documentation built on Oct. 15, 2023, 1:06 a.m.