guide to using excel for basic statistical applications to accompany business statistics: a decision...

Guide to Using Excel For Basic Statistical Applications

Guide to Using Excel For Basic Statistical Applications

To AccompanyTo Accompany

Business Statistics: A Decision Making Approach, 6th Ed.

Chapter 12:Chapter 12:

Goodness of Fit Tests and Contingency Goodness of Fit Tests and Contingency AnalysisAnalysis

ByBy

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

Copyright, 2005Copyright, 2005

Chapter 12 Excel Examples

Goodness of Fit Test

Woodtrim ProductsContingency Analysis

Benton Industries

Goodness of Fit - Woodtrim ProductsGoodness of Fit - Woodtrim Products

Issue: Issue:

The company has recently become concerned The company has recently become concerned that the ripsaw may not be cutting to the that the ripsaw may not be cutting to the manufacture’s specifications manufacture’s specifications

Objective: Objective:

Use Excel to determine whether the data set’s Use Excel to determine whether the data set’s mean and standard deviation meet the manufacturer’s mean and standard deviation meet the manufacturer’s specifications. Data file is specifications. Data file is WoodtrimWoodtrim.xls.xls

Open File Woodtrim.xls

Goodness of Fit – Woodtrim Products

Label columns and define classes.


Use the COUNTIF function to find the number of data values less than -.02.


Again use the COUNTIF only this time subtract the observations in the previous cell to find the number of data values in the current cell.


Continue to use COUNTIF while subtracting the observations in the previous cell to find the number of data values in the current cell.


Notice change in the COUNTIF function for the final cell. Also, sum the observations.


Use the NORMDIST function to find the expected probability of values less than -.02 given the expected mean and standard deviation.


Continue to use the NORMDIST function to generate probabilities, but to get discrete values, subtract out the sum of the preceding cells.


To find the Expected Frequencies multiply the Normal Distribution values by 300.


Compute the Chi square value in column N using the formula for each combination of cells.


Summing the individual values gives the Chi square value.


To find the p-value click on the Function button, then select Statistics and CHITEST.


Enter the ranges for the Actual and Expected frequencies.


The p-value is determined.


Contingency Analysis - Benton IndustriesContingency Analysis - Benton Industries

Issue: Issue:

The company was interested in determining The company was interested in determining the relationship between absenteeism and marital the relationship between absenteeism and marital status. status.

Objective: Objective:

Use Excel to determine whether there is a Use Excel to determine whether there is a statistically significant relationship between statistically significant relationship between absenteeism and marital status. Data file is absenteeism and marital status. Data file is Benton.xlsBenton.xls

Open File Benton.xls

Contingency Analysis – Benton Industries

Use this Formula to find the expected number of single people with zero absences.


Using similar formulas determine the expected values for all the combinations of absentee rate and marital status Shown in green.


Use this formula to determine the Chi Square value.


To find the Chi Square critical value, click on the function button, then select Statistical and CHIINV.


Enter the appropriate Probability and Degrees of Freedom to find the critical value.


guide to using excel for basic statistical applications to accompany business statistics: a decision...

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