statsmodels.stats.contingency_tables.SquareTable.test_ordinal_association

SquareTable.test_ordinal_association(row_scores=None, col_scores=None)

Assess independence between two ordinal variables

This is the ‘linear by linear’ association test, which uses weights or scores to target the test to have more power against ordered alternatives.

Parameters:

row_scoresarray_like, optional

An array of numeric row scores

col_scoresarray_like, optional

An array of numeric column scores

Returns:

Bunch

A bunch with attributes

• statisticfloat

  The test statistic.

• null_meanfloat

  The expected value of the test statistic under the null hypothesis.

• null_sdfloat

  The standard deviation of the test statistic under the null hypothesis.

• zscorefloat

  The Z-score for the test statistic.

• pvaluefloat

  The p-value for the test.

Notes

The scores define the trend to which the test is most sensitive.

Using the default row and column scores gives the Cochran-Armitage trend test.