statsmodels.stats.proportion.confint_proportions_2indep¶

statsmodels.stats.proportion.confint_proportions_2indep(count1, nobs1, count2, nobs2, method=None, compare='diff', alpha=0.05, correction=True)[source]

Confidence intervals for comparing two independent proportions

This assumes that we have two independent binomial samples.

Parameters
count1, nobs1float

Count and sample size for first sample.

count2, nobs2float

Count and sample size for the second sample.

methodstr

Method for computing confidence interval. If method is None, then a default method is used. The default might change as more methods are added.

diff:
• ‘wald’,

• ‘agresti-caffo’

• ‘newcomb’ (default)

• ‘score’

ratio:
• ‘log’

• ‘score’

odds-ratio:
• ‘logit’

• ‘score’

comparestr in [‘diff’, ‘ratio’ ‘odds-ratio’]

If compare is diff, then the confidence interval is for diff = p1 - p2. If compare is ratio, then the confidence interval is for the risk ratio defined by ratio = p1 / p2. If compare is odds-ratio, then the confidence interval is for the odds-ratio defined by or = p1 / (1 - p1) / (p2 / (1 - p2).

alphafloat

Significance level for the confidence interval, default is 0.05. The nominal coverage probability is 1 - alpha.

Returns
low, upp

Notes

Status: experimental, API and defaults might still change.

more methods will be added.