Section 8.4 (p.473)

 

1.         Let l1 < l2, increases in S Xi.

 

2.         Let Y = S (Xi-m)2 and s12 < s22.  increases in Y.

 

3.         Let a1 < a2,  increases in P Xi.

 

5.         Let q1 < q2, increases in S d(Xi)

 

6.         Since the probability of rejecting H0 is always 0.05, the power function is 0.05 for every q.

 

7.         The joint pdf of X1,…, Xn has a MLR in SXi2 (Exercise 2). Therefore by Theorem 1 the test that rejects H0 if SXi2 ³ c is a UMP test. It is possible for any a0 because SXi2 is continuous and the constant c con be derived from the equation Pr(SXi2 ³ c | s2=2) = a0.

 

9.         The joint pdf of X1,…, Xn has a MLR in SXi and the UMP test rejects H0 when SXi ³ c (Example 3). Note that SXi has a Binomial(n, p) distribution. When a0 = 0.0577 = Pr(SXi ³ c | p=1/2), it can be shown that c = 14 (use table on p.684). When a0 = 0.0207, c = 15.

 

10.       The joint pdf of X1,…, Xn has a MLR in SXi (Exercise 1). Therefore by Theorem 1 the test that rejects H0 if SXi2 ³ c is a UMP test. To determine c, we have a0 = 0.0143 = Pr(SXi ³ c | l=1). Since SXi has a Poisson distribution with mean 10, we have c = 18 (use table on p. 688).

 

14.       The joint pdf of X1,…, Xn has a MLR in because

 increases in if b2>b1.

Now we apply the results from Exercise 11, which can be proved in the same manner as the textbook proves Theorem 1. Therefore, the test that rejects H0 if  is a UMP test. Or equivalently, rejects H0 if .

 

17.       The test that rejects H0 if  is a UMP test (Example 4). Given a0=0.025, we have

            (a) . Since p(m|d*) is increasing in m, we want to find the smallest n for which p(m=0.5|d*) ³ 0.9. That is

 

            (b)