Quasi-asymmetry model for square tables with nominal categories

Abstract

For an R×R square contingency table with nominal categories, the present paper proposes a model which indicates that the absolute values of log odds of the odds ratio for rows i and j and columns j and R to the corresponding symmetric odds ratio for rows j and R and columns i and j are constant for every i<j<R. The model is an extension of the quasi-symmetry model and states a structure of asymmetry of odds ratios. An example is given.

Keywords:

• contingency table
• nominal category
• quasi-symmetry

2010 Mathematics Subject Classification :

• 62H17

Acknowledgements

The author thanks Professor S. Tomizawa at Tokyo University of Science for helpful comments and suggestions. The author is also thankful to the two anonymous reviewers for their constructive suggestions.