Introductory Biostatistics

Chapter 5

5.1 (a)H 0 :m¼30;HA:m>30;(b)H 0 :m¼ 11 :5;HA:m 011 :5;(c)hypoth-

eses are for population parameters;(d)H 0 :m¼ 31 :5;HA:m< 31 :5;(e)

H 0 :m¼16;HA:m 0 16;(f)Same as part (c).

5.2 H 0 :m¼ 74 :5.

5.3 H 0 :m¼7250;HA:m<7250.

5.4 H 0 :p¼38;HA:p>38.

5.5 H 0 :p¼ 0 :007;HA:m> 0 :007.

pvalue¼Prðb20 cases out of 1000jH 0 Þ

H 0 :mean¼ð 1000 Þð 0 : 007 Þ¼ 7

variance¼ð 1000 Þð 0 : 007 Þð 0 : 993 Þ¼ð 2 : 64 Þ^2

z¼

20
7

2 : 64

¼ 4 : 92 ; pvalueF 0

5.6 The mean di¤erence;H 0 :md¼0,HA:md 0 0.

5.7 H 0 :p¼

20 : 5

5000

HA:p>

20 : 5

5000

5.8 H 0 :s¼20,HA:s 0 20.

5.9 One-tailed.

5.10 UnderH 0 :p¼ 0 :25; variance¼pð 1
pÞ= 100 ¼ð 0 : 043 Þ^2

z¼

0 : 18
0 : 25

0 : 043

¼
 1 : 63 ; a¼ 0 : 052

UnderHA:p¼ 0 :15; variance¼pð 1 
pÞ= 100 ¼ð 0 : 036 Þ^2

z¼

0 : 18
0 : 15

0 : 036

¼ 0 : 83 ; b¼ 0 : 2033

The change makesasmaller andblarger.

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