- To calculate the correla on factor (r), go to Excel, Formulas, Sta s cs, and select the CORREL func on.
- To calculate the Regression Equa on and Coe cient of Determina on: a. Select the x,y data
b. Insert a sca er chart from that data
c. Click the chart, go to Chart Design
d. Go to Quick Layout
e. Select Layout 9
f. Then you get the Regression Equa on, and r square.
1) Exercise 23, page 159.
Roadway conges on is a costly item, in both me wasted, and fuel wasted. Let X represent the average annual hours per person spent in tra c delays and let Y represent the average annual gallons of fuel wasted per person in tra c delays.
a) Draw a sca er diagram for the data.
b) Compute r (Coe cient of Correla on).
c) Is there a correla on?
X (hr)
Y (gal)
28
48
5
3
20
24
35
55
20
34
23
38
18
28
5
9
2) Exercise 7, page 172.
Let X represent the total number of jobs in each neighborhood, and let Y represent the number of entry-level jobs in the same neighborhood. A sample of six neighborhoods gave the following informa on (units in hundreds of jobs).
X
Y
16
2
33
3
50
6
28
5
50
9
25
3
a) Calculate the media of jobs.
b) Calculate the media of entry-level jobs.
c) Compute r (Coe cient of Correla on).
d) Draw a sca er diagram for the data, showing the regression line.
e) Calculate the Coe cient of Determina on.
f) Calculate the Regression Equa on.
g) Ques on: If a neighborhood with 40 jobs, how many are predicted to be entry-level jobs?
STA200
Homework 4: Based on Chapter 4.
· To calculate the correlation factor (r), go to Excel, Formulas, Statistics, and select the CORREL function.
· To calculate the Regression Equation and Coefficient of Determination:
a. Select the x,y data
b. Insert a scatter chart from that data
c. Click the chart, go to Chart Design
d. Go to Quick Layout
e. Select Layout 9
f. Then you get the Regression Equation, and r square.
1) Exercise 23, page 159. Roadway congestion is a costly item, in both time wasted, and fuel wasted. Let X represent the average annual hours per person spent in traffic delays and let Y represent the average annual gallons of fuel wasted per person in traffic delays. a) Draw a scatter diagram for the data. b) Compute r (Coefficient of Correlation). c) Is there a correlation?
|
X (hr) |
Y (gal) |
|
28 |
48 |
|
5 |
3 |
|
20 |
24 |
|
35 |
55 |
|
20 |
34 |
|
23 |
38 |
|
18 |
28 |
|
5 |
9 |
2) Exercise 7, page 172. Let X represent the total number of jobs in each neighborhood, and let Y represent the number of entry-level jobs in the same neighborhood. A sample of six neighborhoods gave the following information (units in hundreds of jobs).
|
X |
Y |
|
16 |
2 |
|
33 |
3 |
|
50 |
6 |
|
28 |
5 |
|
50 |
9 |
|
25 |
3 |
a) Calculate the media of jobs. b) Calculate the media of entry-level jobs. c) Compute r (Coefficient of Correlation). d) Draw a scatter diagram for the data, showing the regression line. e) Calculate the Coefficient of Determination. f) Calculate the Regression Equation. g) Question: If a neighborhood with 40 jobs, how many are predicted to be entry-level jobs?