To find whether the correlation is low, moderate or high
University Crime: FBI Report Do larger universities tend to have more property crime? University crime statistics are affected by a variety of factors. The surrounding community, accessibility given to outside visitors, and many other factors influence crime rate. Let x be a variable that represents student enrollment (in thousands) on a university campus. Let y be a variable that represents the number of burglaries in a year on a university campus. A random sample of n = 8 universities in California gave the following information about enrollments and annual burglary incidents. (References: Crime in the United States, Federal Bureau of Investigation.)
|
x
|
12.5
|
30.0
|
24.5
|
14.3
|
7.5
|
27.7
|
16.2
|
20.01
|
|
y
|
26
|
73
|
39
|
23
|
15
|
30
|
15
|
25
|
(a.) Make a scatter diagram and draw the line you think best fits the data.
(b.) Would you say the correlation is low, moderate, or high? Positive or negative?
(c.) Using a calculator, verify that Σx = 152,8 Σx² = 3350.98, Σy = 246, Σy² = 10,030, and Σxy = 5488.4. Compute r. As x increases, does the value of r imply that y should tend to increase or decrease? Explain.