Introductory Biostatistics

5.11 UnderH 0 :z¼

0 : 22
0 : 25

0 : 043

¼
 0 : 70 ; a¼ 0 : 242

UnderHA:z¼

0 : 22
0 : 15

0 : 036

¼ 1 : 94 ; b¼ 0 : 026

The new change makesalarger andbsmaller.

5.12 pvalue¼Prðp< 0 :18 orp> 0 : 32 Þ

¼2Przb

0 : 32
0 : 25

0 : 043

¼ 1 : 63



¼ 0 : 1032

5.13 p¼ 0 : 18

SEðpÞ¼ 0 : 0385

0 : 18 Gð 1 : 96 Þð 0 : 0385 Þ¼ð 0 : 105 ; 0 : 255 Þ;which includes 0: 25

5.14 SEðxÞ¼ 0 :054; cut point fora¼ 0 :05: 4: 86 Gð 1 : 96 Þð 0 : 054 Þ¼ 4 :75 and
4.96.

m¼ 4 : 86 þ 0 : 1

¼ 4 : 96

z¼

4 : 96
4 : 96

0 : 054

¼ 0 ; power¼ 0 : 5

5.15 SEðxÞ¼ 1 :11; cut points fora¼ 0 :05: 128: 6 Gð 1 : 96 Þð 1 : 11 Þ¼ 126 :4 and
130.8.

m¼ 135

power¼ 1 
Prð 126 : 4 axa 130 : 8 jm¼ 135 Þ

F 1 : 0

Chapter 6

6.1 Proportion isp¼ 0 :227;z¼
 1 :67;pvalue¼ð 2 Þð 0 : 0475 Þ¼ 0 :095.

6.2 w^2 ¼ 75 :03;pvalueG0.

ANSWERS TO SELECTED EXERCISES 515