The Essentials of Biostatistics for Physicians, Nurses, and Clinicians

Solutions to Selected Exercises 187

It appears obvious that group 1 has the larger numbers.

From the table for the Wilcoxon rank - sum test when n 1 = n 2 = 12 we have for

T = 209.50. The p - value given here was obtained using the following SAS code:

data schizo;

input group$ season$ nschizo

;

datalines;

g2 summer 9

g2 summer 15

g2 summer 17

g2 summer 21

g2 summer 25

g2 summer 28

g2 spring 10

g2 spring 13

g2 spring 14

g2 spring 18

g2 spring 20

g2 spring 22

g1 fall 19

g1 fall 20

g1 fall 23

g1 fall 27

g1 fall 32

g1 fall 33

g1 winter 35

g1 winter 36

g1 winter 36

g1 winter 38

g1 winter 41

g1 winter 43

;

run;

ods graphics on;

proc npar1way data = schizo;

class group;

var nschizo;

run;

ods graphics off;

data schizo;

input group$ season$ nschizo

;

datalines;

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