One can determine how old a tree is by counting its rings, but
that Requires cutting the tree down. A forester wanted to
investigate whether or not the age of a tree can be estimated
simply from its diameter so they measured 27 trees of the same
species that had been cut down, and counted the rings to determine
the ages of the trees. The following are the data
collected.
Diameter in inches
Age in years
Diameter in inches
Age in years
Diameter in inches
Age in years
Diameter in inches
Age in years
3.8
4
6.8
12
9.3
23
11.5
34
3.8
5
6.9
13
9.9
25
11.7
35
5.7
8
7.6
14
9.8
28
11.7
38
5.0
8
7.6
16
10.6
29
11.7
38
5.8
8
8.1
18
10.6
30
12.5
40
6.9
10
9.0
20
10.4
30
12.3
42
6.1
10
8.8
22
11.3
33
Create a residual graph
Use diameter for the x-axis and residuals for the
y-axis
Are the assumptions and conditions met for this linear model to
be appropriate for this data? Please make sure you address
the following:
Quantitative Variable Condition
Straight Enough Condition
Outlier Condition
Does the Plot Thicken? Condition.