def _calculate_robust_standard_errors(self):
    'Calculate robust standard errors for our two sets of coefficients by taking the square root of the diagonal\n        values in the variance covariance matrices\n        '
    (_robust_cov0, _robust_cov1) = self._calculate_robust_covariance()
    _std_error0 = np.sqrt(np.diag(_robust_cov0))
    _std_error1 = np.sqrt(np.diag(_robust_cov1))
    return (_std_error0, _std_error1)
Calculate robust standard errors for our two sets of coefficients by taking the square root of the diagonal
values in the variance covariance matrices
def _calculate_robust_standard_errors(self):
    'Calculate robust standard errors for our two sets of coefficients by taking the square root of the diagonal\n        values in the variance covariance matrices\n        '
    (_robust_cov0, _robust_cov1) = self._calculate_robust_covariance()
    _std_error0 = np.sqrt(np.diag(_robust_cov0))
    _std_error1 = np.sqrt(np.diag(_robust_cov1))
    return (_std_error0, _std_error1)