Inverse of the Gompertz Model

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

Usage

inv_gompertz4(y, a, b, c, d)

inv_gompertz4_fixed(y, fixed_a, b, c, d)

Arguments

y

Numeric vector. Observed response.

a, b, c, d

Numeric scalars. Model parameters.

fixed_a

Numeric scalar. Externally fixed lower asymptote.

Value

Numeric vector of x values.

See also

Other inverse-functions: inv_logistic4(), inv_logistic5(), inv_loglogistic4(), inv_loglogistic5()