**Poisson Probability**

Steel RGD, Torrie JH Dickey DA (1997) Principles and Procedures of Statistics.
A Biomedical Approach. The McGraw-Hill Companies, Inc New York. p. 558

**The C Test**
The C Test was the original test used to compare two counts, and quoted by most jouirnal and text books. It
is based on the ratio of the two λs under comparison

Przyborowski J and Wilenski H (1940) Homogeneity of results in testing samples
from Poisson series. Biometrika 31:313-323.

**The E Test**
The E Test is based on a difference between the two λs under comparison, and is marginally more
powerful, but requires extensive computing power because it requires mathematical iteration.

Krishnamoorthy, K and Thomson, J. (2004). A more powerful test for comparing
two Poisson means. Journal of Statistical Planning and Inference, 119, 249-267.
Program adapted from FORTRAN program by same author, downloaded from
www.ucs.louisiana.edu/~kxk4695/