Introductory Biostatistics

Action Level Odds Ratio

Rarely 1.93

Occasionally 24.3

Frequently 33.8

Very frequently 5.2

(b)The general odds ratio is 6.15; given two physician of di¤erent types,

the odds that the resident committing more unnecessary transfusion

is 6.15; Yes, this agrees with the results in part(a).

1.46 Factor Odds Ratio

X-ray 8.86

Stage 5.25

Grade 3.26

Chapter 2

2.1 Median¼193.

2.2 Median for 1979 is 47.6, for 1987 is 27.8.

2.8 Median from graph is 83, exact is 86.

2.9 xs^2 ss=x

Men 84.71 573.68 23.95 28.3%

Women 88.51 760.90 27.58 31.2%

2.11 x¼ 168 :75,s^2 ¼ 1372 :75,s¼ 37 :05.

2.12 x¼ 3 :05,s^2 ¼ 0 :37,s¼ 0 :61.

2.13 x¼ 112 :78,s^2 ¼ 208 :07,s¼ 14 :42.

2.14 x¼ 100 :58,s^2 ¼ 196 :08,s¼ 14 :00.

2.15 x¼ 0 :718,s^2 ¼ 0 :261,s¼ 0 :511.

2.16 xs^2 s

Age 65.6 243.11 15.19

SBP 146.2 379.46 19.48

2.17 xs^2 s

Females 107.6 4373.5 66.1

Males 97.8 1635.9 40.4

2.18 x¼ 0 :22,s^2 ¼ 0 :44,s¼ 0 :66.

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