Bus and subway ridership for the summer months in London, England, is believed to be tied heavily to the number of tourists visiting the city. During the past 12 years, the data on the next page have been obtained:
|
YEAR (SUMMER MONTHS)
|
NUMBER OF TOURISTS (IN MILLIONS)
|
RIDERSHIP (IN MILLIONS)
|
|
1
|
7
|
1.5
|
|
2
|
2
|
1.0
|
|
3
|
6
|
1.3
|
|
4
|
4
|
1.5
|
|
5
|
14
|
2.5
|
|
6
|
15
|
2.7
|
|
7
|
16
|
2.4
|
|
8
|
12
|
2.0
|
|
9
|
14
|
2.7
|
|
10
|
20
|
4.4
|
|
11
|
15
|
3.4
|
|
12
|
7
|
1.7
|
a) Plot these data and decide if a linear model is reasonable.
b) Develop a regression relationship.
c) What is expected ridership if 10 million tourists visit London in a year?
d) Explain the predicted ridership if there are no tourists at all.
e) What is the standard error of the estimate?
f) What is the model's correlation coefficient and coefficient of determination?