Friday, November 30, 2007

Answers to Friday's work

Chapter 14 #12a)
1. 0.45
2. 0.87

Chapter 14 #12b)
1. (0.55)^2 = 0.3025
2. (0.45)^2 = 0.2025
3. 1 - (0.87)^2 = 0.2431

Chapter 15 #8
a) P(male | cat) = 6/18 = 0.333
b) P(cat | female) = 12/28 = 0.429
c) P(female | dog) = 16/24

Chapter 15 #10
a) 0.62
b) 0.26/0.30 = 0.867
c) 0.12/0.62 = 0.194
d) 0.66

Chapter 15 #24
No! P(death penalty) = 62%, but P(dp | rep) = 26/30 = 86.7% and P(dp
| dem) = 12/36 = 33%, so party is clearly NOT independent of party!

Quiz on Monday!!!