def inverse_deriv(self, z):
    "\n        Derivative of the inverse of the logit transform\n\n        Parameters\n        ----------\n        z : array_like\n            `z` is usually the linear predictor for a GLM or GEE model.\n\n        Returns\n        -------\n        g'^(-1)(z) : ndarray\n            The value of the derivative of the inverse of the logit function\n        "
    t = np.exp(z)
    return (t / ((1 + t) ** 2))
Derivative of the inverse of the logit transform

Parameters
----------
z : array_like
    `z` is usually the linear predictor for a GLM or GEE model.

Returns
-------
g'^(-1)(z) : ndarray
    The value of the derivative of the inverse of the logit function
def inverse_deriv(self, z):
    "\n        Derivative of the inverse of the logit transform\n\n        Parameters\n        ----------\n        z : array_like\n            `z` is usually the linear predictor for a GLM or GEE model.\n\n        Returns\n        -------\n        g'^(-1)(z) : ndarray\n            The value of the derivative of the inverse of the logit function\n        "
    t = np.exp(z)
    return (t / ((1 + t) ** 2))