Math153-DB1 Name(s): _________________________________________

9/05 _______________________________________________

_______________________________________________

Project 5: (10 points) Analyze class survey: Work Hours and Study Hours

Due: on or before Friday, October 7, 2005.

READ EACH SECTION FIRST BEFORE USING MINTAB14.

1) Open Minitab14.

Enter the class data (DB1) for WkDB1 and StudyDB1. (Questions How many hours per week will you be working in a typical week during this semester? How many hours per week do you plan to study for this course this semester?)

Enter the data below. There are two cases for which there was no numerical response for the study question. Just leave that cell blank. There are 19 cases.

WkDB1	StudyDB1
40	2
38
0	6
17	10
25	7
28	2
15	3
42	20
40	6
0	20
29
15	10
15	3
15	7
30	2
20	4
34	4
14	6
15	2

2) Find the equation of the regression line. We would like to know if the hours per week spent working influences the hours per week planned studying for the course.

IMPORTANT: Use StudyDB1 as the response variable or y variable; use WkDB1 as the predictor variable or x variable.

Pull down the menu Stat, Regression, Regression,

For the Response variable, double click on StudyDB1.

For the Predictor variable, double click on WkDB1.

OK

DO NOT ROUND OFF.

Equation of Regression Line: ____________________________________________________________

3) Draw a scatterplot.

4) Type your name in the Session Window and print the Worksheet (the data), the Session Window (the regression analysis), and the Scatterplot.

-OVER-

5) Which observations are influential or unusual and why? Circle and label observations on your scatterplot which are influential and unusual (i.e. having a large standardized residual and way off the line).

a) Influential: Observation #(s): (Note: there may be none.)__________________

Why influential?

b) Unusual (large standardized residual): Observation #(s) ____________________

Why unusual?

6) Can we generalize this interpretation to the population of day Math153 students taught by the instructor? _____

Use the p-value. Explain briefly.

7) Do you think there is an association between work hours and planned hours of study for the course? ______________ Why or why not?