In the notation of Exercise 2.28, let R = Y2/Y1. Show that the first four cumulants of this ratio are and explain what is meant by the notation κr

(λ).

κ1 (R) = κ1 (λ)

κ2 (R) = 2κ2 (λ)/ (n + 2)

κ3 (R) = 8κ3 (λ)/ {(n + 2)(n + 4)}

κ4 (R) = 48κ4 (λ)/ {(n + 2)(n + 4)(n + 6)}

+ 48nκ

2 2 (λ)/{(n + 2)

2 (n + 4)(n + 6)}