statsmodels.stats.contingency_tables.cochrans_q¶

statsmodels.stats.contingency_tables.
cochrans_q
(x, return_object=True)[source]¶ Cochran’s Q test for identical binomial proportions.
 Parameters
 xarray_like, 2d (N, k)
data with N cases and k variables
 return_objectboolean
Return values as bunch instead of as individual values.
 Returns
 Returns a bunch containing the following attributes, or the
 individual values according to the value of `return_object`.
 statisticfloat
test statistic
 pvaluefloat
pvalue from the chisquare distribution
Notes
Cochran’s Q is a ksample extension of the McNemar test. If there are only two groups, then Cochran’s Q test and the McNemar test are equivalent.
The procedure tests that the probability of success is the same for every group. The alternative hypothesis is that at least two groups have a different probability of success.
In Wikipedia terminology, rows are blocks and columns are treatments. The number of rows N, should be large for the chisquare distribution to be a good approximation.
The Null hypothesis of the test is that all treatments have the same effect.
References
http://en.wikipedia.org/wiki/Cochran_test SAS Manual for NPAR TESTS