logistic5_fn {drda} R Documentation

5-parameter logistic function

Description

Evaluate at a particular set of parameters the 5-parameter logistic function.

Usage

logistic5_fn(x, theta)

Arguments

 x numeric vector at which the logistic function is to be evaluated. theta numeric vector with the five parameters in the form c(alpha, beta, eta, phi, nu).

Details

The 5-parameter logistic function ⁠f(x; theta)⁠ is defined here as

alpha + (beta - alpha) / (1 + nu * exp(-eta * (x - phi)))^(1 / nu)

where theta = c(alpha, beta, eta, phi, nu), beta > alpha, and nu > 0.

Value

Numeric vector of the same length of x with the values of the logistic function.

[Package drda version 1.0.0 Index]