Categorical Data Analysis Using The SAS® System, 2nd Edition

11.2. Estimating Tolerance Distributions

Table 11.1 displays data from an experiment in which animals were exposed to bacterial challenges after having one-quarter of their spleen removed (splenectomy). After 96 hours, their survival status was assessed. The stimulus is the bacterial challenge, and interest lies in assessing the tolerances of the animals’ immune systems to the bacterial challenge after they have had partial splenectomies (Koch and Edwards 1985).

Table 11.1. Status 96 Hours After Bacterial Challenge

	Status
Bacterial Dose	Dead	Alive
1.2 × 103	0	5
1.2 × 104	0	5
1.2 × 105	2	3
1.2 × 106	4	2
1.2 × 107	5	1
1.2 × 108	5	0

In bioassay analysis, you make the assumption that responses of subjects are determined through a tolerance distribution. This means that ...