For the Poisson regression Example 9.9 (Frome), analyze the data with a linear mean function in the two variables and compute variance estimates of the parameters. For the sum-of-squares function S(β)...

For the Poisson regression Example 9.9 (Frome), analyze the data with a linear mean function in the two variables and compute variance estimates of the parameters.

For the sum-of-squares function S(β) (from (9.8.1)), compute the derivative in the direction d; that is, take the derivative of S(β + td) with respect to t.