The remainder of the paper is organized as follows. In
Section 2 we provide background information on the Poisson
distribution as well as review the marginal maximum likelihood
estimation method for the gamma prior parameters. In
Section 3 we propose and derive sample-size determination
methods for the ratio of two independent Poisson rate parameters.
We continue in Section 4 with two real-life examples for
sample-size determination using the conjugate gamma prior.
Finally, in Section 5 we conclude with brief comments.