Collapsibility of Multidimensional Contingency Tables to Tables of Smaller Dimension. Technical Report No. 12

摘要

Multidimensional contingency tables can be summed over factors, without affecting the log-linear parameters describing interactions of other factors, under less restrictive conditions than generally recognized. Examples are given that contradict the collapsibility theorem of Bishop, Fienberg, and Holland. Necessary and sufficient conditions for collapsibility are given, and an example applying the results to categorical data is presented. (ERA citation 08:043091)