twCoefLogitnormMLE: twCoefLogitnormMLE

In logitnorm: Functions for the Logitnormal Distribution

Description

Estimating coefficients of logitnormal distribution from mode and upper quantile

Usage

twCoefLogitnormMLE(mle, quant, perc = 0.999)

Arguments

mle	numeric vector: the mode of the density function
quant	numeric vector: the upper quantile value
perc	numeric vector: the probability for which the quantile was specified

Value

numeric matrix with columns c("mu","sigma") rows correspond to rows in mle, quant, and perc

Author(s)

Thomas Wutzler

See Also

logitnorm

Examples

# estimate the parameters, with mode 0.7 and upper quantile 0.9
(theta <- twCoefLogitnormMLE(0.7,0.9))

x <- seq(0,1,length.out=41)[-c(1,41)]	# plotting grid
px <- plogitnorm(x,mu=theta[1],sigma=theta[2])	#percentiles function
plot(px~x); abline(v=c(0.7,0.9),col="gray"); abline(h=c(0.999),col="gray")
dx <- dlogitnorm(x,mu=theta[1],sigma=theta[2])	#density function
plot(dx~x); abline(v=c(0.7,0.9),col="gray")

# vectorized
(theta <- twCoefLogitnormMLE(mle=seq(0.4,0.8,by=0.1),quant=0.9))
    
    # flat
    (theta <- twCoefLogitnormMLEFlat(0.7))

logitnorm documentation built on May 2, 2019, 6:15 p.m.