8.5 Exercises
1. What are Q-Q plots useful for?
2. For the following data, plot the theoretically expected z score as a function of the actual z score (a Q-Q plot).
0
0
0
0
0
0
0.1
0.1
0.1
0.1
0.1
0.2
0.2
0.3
0.3
0.4
0.5
0.6
0.6
0.6
0.6
0.6
0.6
0.6
0.6
0.6
0.7
0.7
0.8
0.8
0.8
0.8
0.8
0.9
1
1
1.1
1.1
1.2
1.2
1.2
1.2
1.2
1.2
1.3
1.3
1.3
1.3
1.3
1.4
1.4
1.5
1.6
1.7
1.7
1.7
1.8
1.8
1.9
1.9
2
2
2
2.1
2.1
2.1
2.1
2.1
2.1
2.1
2.3
2.5
2.7
3
4.2
5
5.7
12.4
15.2
3. For the data in problem 2, describe how the data differ from a normal distribution.
4. For the "SAT and College GPA" case study data, create a contour plot looking at University GPA as a function of Math SAT and High School GPA. Naturally, you should use a computer to do this.
5. For the "SAT and College GPA" case study data, create a 3D plot using the variables University GPA, Math SAT, and High School GPA. Naturally, you should use a computer to do this.
Adapted from Online Statistics Education: A Multimedia Course of Study (onlinestatbook.com), Project Leader: David M. Lane, Rice University. Developed with NSF support. The original work is in the public domain; it is cited here at the authors' request. Changes were made: reformatted as an accessible XYZ web edition with native MathML. License: Public-Domain.