Carmax.com lists numerous Toyota Corollas for sale within a 250 mile radius of Redlands, CA. Listed at the top of the next column are the ages of the cars and the advertised prices.
a) Make a scatterplot for these data.
b) Describe the association between Age and Price of a used Corolla.
c) Do you think a linear model is appropriate?
d) Computer software says that R2 = 75.2%. What is the correlation between Age and Price?
e) Explain the meaning of R2 in this context.
f) Why doesn't this model explain 100% of the variability in the price of a used Corolla?
Age (yr) Price Advertised ($)
9 ……………………… 11,599
4 ……………………… 14,998
4 ……………………… 12,998
7 ……………………… 10,998
3 ……………………… 15,998
5 ……………………… 14,599
5 ……………………… 11,559
8 ……………………… 9,998
9 ……………………… 9,998
1 ……………………… 15,998
5 ……………………… 12,599
3 ……………………… 16,998
5 ……………………… 13,998