# twCoefLogitnormCi: twCoefLogitnormCi In logitnorm: Functions for the Logitnormal Distribution

## Description

Calculates mu and sigma of the logitnormal distribution from lower and upper quantile, i.e. confidence interval.

## Usage

 ```1 2``` ```twCoefLogitnormCi(lower, upper, perc = 0.975, sigmaFac = qnorm(perc), isTransScale = FALSE) ```

## Arguments

 `lower` value at the lower quantile, i.e. practical minimum `upper` value at the upper quantile, i.e. practical maximum `perc` numeric vector: the probability for which the quantile was specified `sigmaFac` sigmaFac = 2 is 95% sigmaFac = 2.6 is 99% interval `isTransScale` if true lower and upper are already on logit scale

## Value

named numeric vector: mu and sigma parameter of the logitnormal distribution.

Thomas Wutzler

## See Also

`logitnorm`

## Examples

 ```1 2 3 4 5 6 7 8``` ```mu = 2 sd = c(1,0.8) p = 0.99 lower <- l <- qlogitnorm(1 - p, mu, sd ) # p-confidence interval upper <- u <- qlogitnorm(p, mu, sd ) # p-confidence interval cf <- twCoefLogitnormCi(lower,upper, perc = p) all.equal( cf[,"mu"] , c(mu,mu) ) all.equal( cf[,"sigma"] , sd ) ```

logitnorm documentation built on Jan. 7, 2021, 9:09 a.m.