dBeta_mu: Beta probability density function

In FlexReg: Regression Models for Bounded Responses

Description

The function computes the probability density function of the beta distribution with a mean-precision parameterization.

Usage

dBeta_mu(x, mu, phi)

Arguments

x	a vector of quantiles.
mu	the mean parameter. It must lie in (0, 1).
phi	the precision parameter. It must be a positive real value.

Details

The beta distribution has density

\frac{Γ{(φ)}}{Γ{(μφ)}Γ{((1-μ)φ)}}x^{μφ-1}(1-x)^{(1-μ)φ-1}

for 0<x<1, where 0<μ<1 identifies the mean and φ>0 is the precision parameter.

Value

A vector with the same length as x.

References

Ferrari, S.L.P., and Cribari-Neto, F. (2004). Beta Regression for Modeling Rates and Proportions. Journal of Applied Statistics, 31(7), 799–815. doi:10.1080/0266476042000214501

Examples

dBeta_mu(x = c(.5,.7,.8), mu = 0.3, phi = 20)

FlexReg documentation built on Jan. 17, 2022, 5:06 p.m.