Question

1. Genotypes AA, Aa, and aa occur with probabilities (p1,p2,p3). For n = 3 independent observa-

   tions the observed frequencies are (y1, y2, y3).

   1. (a) Explain how you can determine y3 from knowing y1 and y2. Thus the multinomial distribution

      of (y1, y2, y3) is actually two-dimensional.

   2. (b) Show the set of all possible observations, (y1, y2, y3) with n = 3.

   3. (c) Suppose (p1, p2, p3) = (0.25, 0.5, 0.25). Find the the probability that (y1, y2, y3) = (1, 2, 0).

   4. (d) Refer to (c). What probability distribution does y1 alone have? Specified the values of the

      sample size index and parameter for that distribution.

Answer 1