Introductory Biostatistics

7.18 Source of Variation SS df MS FStatistic pValue

Between samples 55.44 2 27.72 2.62 0.1059

Within samples 158.83 15 10.59

Total 214.28 17

7.19 Source of Variation SS df MS FStatistic pValue

Between samples 74.803 3 24.934 76.23 0.0001

Within samples 4.252 13 0.327

Total 79.055 16

7.20 Source of Variation SS df MS FStatistic pValue

Between samples 40.526 2 20.263 3.509 0.0329

Within samples 527.526 126 5.774

Total 568.052 128

7.21 Source of Variation SS df MS FStatistic pValue

Between samples 57.184 3 19.061 37.026 <0.0001

Within samples 769.113 1494 0.515

Total 826.297 1497

7.22 For exposed group:

Source of Variation SS df MS FStatistic pValue

Between samples 5,310.032 2 2,655.016 0.987 0.3738

Within samples 845,028 314 2,691.172

Total 850,338.032 316

For nonexposed group:

Source of Variation SS df MS FStatistic pValue

Between samples 10,513.249 2 5,256.624 2.867 0.0583

Within samples 607,048 331 1,833.982

Total 617,561.249 333

7.23 Factor: age

(a) t¼ 1 :037,pvalue¼ 0 :3337;(b)z¼
 0 :864,pvalue¼ 0 :3875.

Factor: acid

(a) t¼
 1 :785,pvalue¼ 0 :080;(b)z¼ 2 :718,pvalue¼ 0 :0066.

ANSWERS TO SELECTED EXERCISES 523