ch13 excel

8/12/2019 Ch13 Excel

1/63

Guide to Using Excel For Basic

Statistical Applications

To Accompany

A Course I n Business Statistics, 4thEd.

Chapter 13:

Multiple Regression Analysis and Model

Building

By

Groebner, Shannon, Fry, & SmithPrentice-Hall Publishing Company

Copyright, 2006

8/12/2019 Ch13 Excel

2/63

Chapter 14 Excel

Examples

Multiple Regression

First City Real Estate

Multiple Regression

Dummy Variable


Curvilinear Regression

Ashley Investment Services Interaction Effects

Ashley Investment Services

More Examples

8/12/2019 Ch13 Excel

3/63

Chapter 14 Excel

Examples

Residual Analysis


8/12/2019 Ch13 Excel

4/63

Mult ip le Regression

Firs t City Real Estate

Issue:

First City management wishes to build a

model that can be used to predict sales prices

for residential property.

Objective:

Use Excel to build a multiple regression

model relating sales price to a set of measurablevariables. Data file is First City.xls

8/12/2019 Ch13 Excel

5/63

Open File First City.xls

Mult iple Regression First City Real Estate

8/12/2019 Ch13 Excel

6/63

First click onTools,then

Data Analysis

and finally on

Correlation.


8/12/2019 Ch13 Excel

7/63

Define ranges for Variables. Clickon O.K.


8/12/2019 Ch13 Excel

8/63

The Exceloutput shows

the correlation

between Age

and Square

Feet.


8/12/2019 Ch13 Excel

9/63

Return to thedata sheet, click

on Tools, Data

Analysis and

then Regression.


8/12/2019 Ch13 Excel

10/63

Identify rangeof dependent

and independent

variables. Click

OK.


8/12/2019 Ch13 Excel

11/63

Excel determines theregression model.


8/12/2019 Ch13 Excel

12/63

To determine the

Variance InflationFactors, return to the

data sheet, click on

PHStat, Regression and

Multiple Regression.


8/12/2019 Ch13 Excel

13/63


Identify rangeof dependent

and independent

variables. Click

on VIF thenclick OK.

8/12/2019 Ch13 Excel

14/63


PHStat will find VarianceInflation Factors for all

independent variables.

8/12/2019 Ch13 Excel

15/63

8/12/2019 Ch13 Excel

16/63

Open File

First City.xls

click on the

worksheet

containing

the Area

data.

Mult iple Regression- Dummy Variable


8/12/2019 Ch13 Excel

17/63

Click on

PHStat then

Regression

andMultiple

Regression.



8/12/2019 Ch13 Excel

18/63

Define the Data

ranges for the Y

and X Variable

then select

Regression

Statistics Table,

ANOVACoefficients Table

and VIF.



8/12/2019 Ch13 Excel

19/63

The output shows

improved RegressionStatistics.



8/12/2019 Ch13 Excel

20/63

C il i R l t i h i A hl I t t S i

8/12/2019 Ch13 Excel

21/63

Open File Ashley.xls

File contains values for

20 Investment Advisors.

Curvi l inear Relat ionsh ips Ashley Investment Services


8/12/2019 Ch13 Excel

22/63

To develop thescatter plot

first click on

Chart Wizard

buttonthenselect XY

(Scatter).



8/12/2019 Ch13 Excel

23/63

Define the Data

range and

remember the X

variable must be

in the left

column. You may

have to reversethe columns by

cutting and

pasting.



8/12/2019 Ch13 Excel

24/63

Label the X and Y axis.



8/12/2019 Ch13 Excel

25/63

Find the

scatter plot.


C r i l inear Relat ionsh ips Ashle In estment Ser ices

8/12/2019 Ch13 Excel

26/63

To find theregression

model, return

to the data

sheet, click onTools,then

Data Analysis

and finally

Regression.



8/12/2019 Ch13 Excel

27/63

Identify the

range for the

X and Y

variables.

Then click

OK.



8/12/2019 Ch13 Excel

28/63

The output shows

the R Square

value and the

Regression

Coefficients.



8/12/2019 Ch13 Excel

29/63

To develop a nonlinear model,

return to the data file. Create

a new variable Socialization

Squared.



8/12/2019 Ch13 Excel

30/63


model, click

on Tools,then

Data Analysisand finally

Regression.



8/12/2019 Ch13 Excel

31/63

Identify the

range for the

X and Y

variables.

Then click

OK.



8/12/2019 Ch13 Excel

32/63

The output shows

the R Square

value and the

Regression

Coefficients.



8/12/2019 Ch13 Excel

33/63

For an alternate

way to find a

nonlinear model,

return to the

scatter plot, left

click on any point

on the graph thenright click. Select

Add Trendline.



8/12/2019 Ch13 Excel

34/63

Select

Exponential.



8/12/2019 Ch13 Excel

35/63

This gives

the

Exponential

Regression

Line. To add

the

RegressionEquation,

left click on

the trend

line, thenright click to

Format

Trendline



8/12/2019 Ch13 Excel

36/63

Select

Options.

Check

Display

equation and

Display R-

square.



8/12/2019 Ch13 Excel

37/63

This adds

the

Regression

Equation

and R-

square value

to the TrendLine.


8/12/2019 Ch13 Excel

38/63

In terac t ion Effec ts -

Ash ley Investment Serv ices

Issue:

The director of personnel is trying to determine

whether the model can be improved by separatingobservations between those taken from men and

women.

Objective:

Use Excel to determine whether the relationshipbetween the measures can be improved. Data file is

Ashley-2.xls

8/12/2019 Ch13 Excel

39/63


8/12/2019 Ch13 Excel

40/63

Group the data from males and

females together by identifying

the range of data, then clicking

on Data then Sort.



8/12/2019 Ch13 Excel

41/63

Click on the Chart

Wizard and then (XY)

Scatter. Click Next



8/12/2019 Ch13 Excel

42/63

Click on theSeries Tab.

Identify the

range for data

from Males.



8/12/2019 Ch13 Excel

43/63

Add Females tothe Series and

identify the

appropriate

Data Range.

p y


8/12/2019 Ch13 Excel

44/63

Label the

Chart and

the X and Y

Axes. Then

click Next.

p y

Curvi l inear Relat ionsh ipsAshley Investment Services

8/12/2019 Ch13 Excel

45/63

The scatter plot

now separates

male and female

data points.

p

y


8/12/2019 Ch13 Excel

46/63

To find a

nonlinear model

for each data

group, left click

on any point on

each series then

right click. SelectAdd Trendline

then Exponential.

p

y


8/12/2019 Ch13 Excel

47/63

Add colors

by left

cicking on

each

Trendline,

then right

clickandselect

Format

Trendline.

p

y


8/12/2019 Ch13 Excel

48/63

A nonlinear model can also be

developed by creating new

variables and proceeding as in

the last tutorial.

p

y


8/12/2019 Ch13 Excel

49/63


model, click

on Tools,then

Data Analysisand finally

Regression.

y


8/12/2019 Ch13 Excel

50/63

Identify the

range for the

X and Y

variables.

Then click

OK.


8/12/2019 Ch13 Excel

51/63

The output shows

the R Square

value and the

Regression

Coefficients.

8/12/2019 Ch13 Excel

52/63

Issue:

The company is interested in analyzing the

residuals of the regression model to determine

whether the assumptions are satisfied.

Objective:

Use Excel to analyze residuals from a

regression model. Data file is First City-3.xls

Res idual Analys is -

Firs t City Real Estate

8/12/2019 Ch13 Excel

53/63

Residu al AnalysisFirst City Real Estate

8/12/2019 Ch13 Excel

54/63

Since Excel

requires the

independentvariables to be

adjacent, cut and

paste the

appropriatecolumns.


8/12/2019 Ch13 Excel

55/63

First click on Tools,

then Data Analysisand then on

Regression.


8/12/2019 Ch13 Excel

56/63

Define range for X

and Y Variables.

Excel gives several

options for

Residual Analysis,

but does not haveas complete a set

as Minitab.

8/12/2019 Ch13 Excel

57/63


8/12/2019 Ch13 Excel

58/63

Any of the

residual

plots can

be

adjusted togive a

clearer

picture of

theresidual

pattern.


8/12/2019 Ch13 Excel

59/63

This is the output if

the Normal

Probability Plot

option is selected.


8/12/2019 Ch13 Excel

60/63

While Excel will

notautomatically

generate a

histogram of

residual values,

one can be

generated. Start

with the

Standardized

Residuals.

8/12/2019 Ch13 Excel

61/63

8/12/2019 Ch13 Excel

62/63


8/12/2019 Ch13 Excel

63/63

Size and format the

Histogram output.

Also, close the gaps

between the

rectangles.

ch13 excel

Documents