=+Exchanges in 5-Bromodeoxyuridine-Substituted Chromosomes,” Genetics, 1979: 1251–1264). A Poisson model was hypothesized for the distribution of the number of exchanges. Test the fit of such a model to the accompanying data by first estimating

 and then combining the frequencies for x 5 8 and x 5 9.

x: 0 1 2 3 4 5 6 7 8 9 Frequency: 6 24 42 59 62 44 41 14 6 2