University crime statistics
Question
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, and let y be a variable that represents the number of burglaries in a year on the university campus. A random sample of n = 8 universities in California gave the following information about enrollments and annual burglary incidents.
x 13.7, 29.4, 24.5, 14.3, 7.5, 27.7, 16.2, 20.1
y 23, 76, 39, 23, 15, 30, 15, 25
(a) Make a scatter diagram of the data.
Then visualize the line you think best fits the data.
(b) Use a calculator to verify that Σx = 153.4, Σx2 = 3346.78, Σy = 246, Σy2 = 10330 and Σxy = 5522.9.
*** Compute r. (Round to 3 decimal places.)
As x increases, does the value of r imply that y should tend to increase or decrease? Explain your answer.
i. Given our value of r, y should tend to decrease as x increases.
ii. Given our value of r, y should tend to increase as x increases.
iii. Given our value of r, we can not draw any conclusions for the behavior of y as x increases.
iv. Given our value of r, y should tend to remain constant as x increases.