beta_mm: Obtain the shape parameters of a beta distribution

In bstaton1/StatonMisc: Common Functions Used in B. Staton's Code

Description

Use the method of moments to obtain the shape1 (alpha) and shape2 (beta) parameters when provided either a vector of beta random variables or the sample mean and variance of such a vector.

Usage

beta_mm(mn = NULL, vr = NULL, p = NULL, na.rm = FALSE)

Arguments

mn	numeric vector of length == 1. The mean of a beta random variable. Must be specified if vr is not NULL
vr	numeric vector of length == 1. The variance of a beta random variable. Must be specified if mn is not NULL
p	numeric vector of length > 1. iid beta random variables. Must be NULL if mn and vr are not NULL
na.rm	logical. Do you wish to remove NA elements before calculating mean and variance? Defaults to FALSE and only takes effect if p is not NULL.

Examples

beta_mm(p = rbeta(1e6, 6, 1))
beta_mm(mn = 0.5, vr = 0.04)

bstaton1/StatonMisc documentation built on May 18, 2020, 12:06 a.m.