def deriv2_numdiff(self, p):
    "\n        Second derivative of the link function g''(p)\n\n        implemented through numerical differentiation\n        "
    from statsmodels.tools.numdiff import _approx_fprime_scalar
    p = np.atleast_1d(p)
    return _approx_fprime_scalar(p, self.deriv, centered=True)
Second derivative of the link function g''(p)

implemented through numerical differentiation
def deriv2_numdiff(self, p):
    "\n        Second derivative of the link function g(p)\n\n        implemented through numerical differentiation\n        "
    from statsmodels.tools.numdiff import _approx_fprime_scalar
    p = np.atleast_1d(p)
    return _approx_fprime_scalar(p, self.deriv, centered=True)