Introductory Biostatistics

6.3 z¼ð 264 
 249 Þ=

ffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi

264 þ 249

p

¼ 0 : 66 ; pvalue¼ 0 : 5092

orw^2 ¼ 0 :44.

6.4 z¼ 3 :77 orw^2 ¼ 14 :23;pvalue< 0 :01.

6.5 z¼ 4 :60;pvalueF0.

6.6 H 0 : consistent report for a couple, i.e., man and woman agree.

z¼ð 6 
 7 Þ=

ffiffiffiffiffiffiffiffiffiffiffi

6 þ 7

p

¼
 0 : 28 ; pvalue¼ 0 : 7794

6.7 H 0 : no e¤ects of acrylate and methacrylate vapors on olfactory function.

z¼ð 22 
 9 Þ=

ffiffiffiffiffiffiffiffiffiffiffiffiffiffi

22 þ 9

p

¼ 2 : 33 ; pvalue¼ 0 : 0198

6.8 z¼ 4 :11 orw^2 ¼ 16 :89;pvalue< 0 :01.

6.9 z¼ 5 :22 orw^2 ¼ 27 :22;pvalue< 0 :01.

6.10 z¼ 7 :44 orw^2 ¼ 55 :36;pvalue< 0 :01.

6.11 w^2 ¼ 44 :49;pvalue< 0 :01.

6.12 w^2 ¼ 37 :73;pvalue< 0 :01.

6.13 w^2 ¼ 37 :95;pvalue< 0 :01.

6.14 w^2 ¼ 28 :26;pvalue< 0 :01.

6.15 w^2 ¼ 5 :58;pvalue< 0 :05.

6.16 pvalue¼ 0 :002.

6.17 (a)Pearson’s: w^2 ¼ 11 :35; pvalue¼ 0 :001;(b) Pearson’s with Yates’
correction: wc^2 ¼ 7 :11; pvalue¼ 0 :008; (c) Fisher’s exact: pvalue¼
0 :013.

6.18 pvalue¼ 0 :018.

6.19 w^2 ¼ 14 :196; df¼3;pvalue< 0 :05.

6.20 For males:w^2 ¼ 6 :321; df¼3;pvalue¼ 0 :097; for females:w^2 ¼ 5 :476;
df¼3;pvalue¼ 0 :140.

6.21 For men:
Myocardial infarction:w^2 ¼ 0 :16;pvalue> 0 :05.
Coronary death:w^2 ¼ 8 :47;pvalue< 0 :01.

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