To see how it works, first sort your values:
1. -1.4
2. -1.2
3. -1.11
4. -1.08
5. -1.08
6. -1.08
7. -.75
8. -.73
<---------------p25=(-.73-.57)/2=-.65
9. -.57
10. -.57
11. -.57
12. -.51
13. -.48
14. -.48
15. -.4
16. -.3
17. -.09
18. -.07
19. .47
20. .49
21. .49
22. .54
23. .67
24. .69
<---------------p75=(.69 + .78)/2 = .735
25. .78
26. .87
27. .94
28. .96
29. 1.15
30. 1.2
31. 1.46
32. 1.48
Tom Trikalinos, MD
[email protected]
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