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) 