In a genetics experiment, investigators looked at 300 chromosomes of a particular type and counted the number of sister-chromatid exchanges on each (“On the Nature of Sister-Chromatid Exchanges in 5-BromodeoxyuridineSubstituted Chromosomes,” Genetics, 1979: 1251–1264). A Poisson model was hypothesized for the distribution of the number of exchanges. Test the fit of a Poisson distribution to the data by first estimating m and then combining the counts for and into one cell.

0 1 2 3 4 5 6 789 Observed Counts 6 24 42 59 62 44 41 14 6 2