All but one of the following statements contains an

5. All but one of the following statements contains an error. Which statement could be
correct?
(a) There is a correlation of 0.54 between the position a football player plays and his weight.
(b) We found a correlation of r = –0.63 between gender and political party preference.
(c) The correlation between the distance travelled by a hiker and the time spent hiking is
r = 0.9 meters per second.
(d) We found a high correlation between the height and age of children: r = 1.12.
(e) The correlation between mid-August soil moisture and the per-acre yield of tomatoes is
r = 0.53.

6. A set of data describes the relationship between the size of annual salary raises and the
performance ratings for employees of a certain company. The least squares regression
equation is
ˆ
y
= 1400 + 2000 x where y is the raise amount (in dollars) and x is the
performance rating. Which of the following statements is not necessarily true?
7. A least-squares regression line for predicting weights of basketball players on the basis of
their heights produced the residual plot below.
What does the residual plot tell you about the linear model?
86 84 82 80 78 76 74 72
30
20
10
0
-10
-20
HEIGHT
RESIDUAL
Residuals versus Height
© 2011 BFW Publishers The Practice of Statistics, 4/e- Chapter 3 121

122 The Practice of Statistics, 4/e- Chapter 3 © 2011 BFW Publishers