Exact Tests for Trends in Ordered Contingency Tables
针对有序列联表，提出基于卡方趋势统计量的精确条件检验方法，相比一般检验能显著提高统计功效，适用于实际中比值比受限的情形。
SUMMARY In an r x c table the probability of a particular outcome conditioned on fixed marginal totals depends on v = (r -1) (c-1) odds-ratio parameters and hence tests of Ho no association against a general alternative have 2V tails. Exact conditional tests are developed for alternatives in which the odds-ratios take restricted values according to the practical context. Use of the appropriate test can lead to substantial increases in power. An exact test based on the x2 trend statistic is recommended on the grounds of power and computational feasibility.