Inverse of the 5PL Model

Solves for x: $$x = c - b\,\log\!\left(\left(\frac{d - a}{y - a}\right)^{1/g} - 1\right)$$

Usage

inv_logistic5(y, a, b, c, d, g, tol = 1e-06)

inv_logistic5_fixed(y, fixed_a, b, c, d, g)

Arguments

y

Numeric vector. Observed response.

a, b, c, d

Numeric scalars. Model parameters.

g

Numeric scalar. Asymmetry parameter.

tol

Numeric scalar. Buffer from asymptotes.

fixed_a

Numeric scalar. Externally fixed lower asymptote.

Value

Numeric vector of x values. NA for out-of-range y.

See also

Other inverse-functions: inv_gompertz4(), inv_logistic4(), inv_loglogistic4(), inv_loglogistic5()