'A confidence interval for the odds ratio.
Parameters
alpha : float
`1 - alpha` is the nominal coverage probability of the
confidence interval.
method : string
The method for producing the confidence interval.  Currently
must be \'normal\' which uses the normal approximation.'

def oddsratio_confint(self, alpha=0.05, method='normal'):

    (lcb, ucb) = self.log_oddsratio_confint(alpha, method=method)
    return (np.exp(lcb), np.exp(ucb))
