BUSINESS RESEARCH METHODS 1

HANDS ON: DISCRIMINANT ANALYSISGROUPS 3 & 6

BUSINESS RESEARCH METHODS 2

Agenda

• Data

• SPSS steps

• SPSS output

BUSINESS RESEARCH METHODS 3

DataDependent Variable: ‘Smoke’ (whether the employee smoked or not)Dependent variable categories: 1 – Non-smoker & 2 – Smoker

Independent variables1. Age2. Days absent sick from work last year3. Self concept score4. Anxiety score

Aim of the analysis is to determine whether the above mentioned independent variables will discriminate between the employees who smoke and who do not

BUSINESS RESEARCH METHODS 4

SPSS steps1. Analyze >> Classify >> Discriminant 2. Select ‘smoke’ as the grouping variable and

enter it into the grouping variable box and in the define range box enter 1 for min and 2 for max

3. Include the independent variables in the Independents box

BUSINESS RESEARCH METHODS 5

SPSS steps contd…4. Click on Statistics button and select Means, Univariate Anovas, Box’s M, Unstandardized and Within-Groups correlation and click Continue

5. Click on Classify button and select Within-groups covariance matric, Summary table, Leave-one-out classification and all the plots. Select Compute from group sizes for prior probabilities and click Continue

BUSINESS RESEARCH METHODS 6

SPSS steps contd…6. Click on Save button. Select Predicted group membership, Discriminant scores and Probabilities of group membership and click Continue

BUSINESS RESEARCH METHODS 7

SPSS output

Case processing summary indicates sample size & missing data

Strong statistical evidence of significant differences between means of smoke and no smoke groups for all IV’s with self-concept and anxiety producing very high value F’s

Mean differences between self-concept scores & anxiety scores may be good discriminators as the difference in values are large

BUSINESS RESEARCH METHODS 8

SPSS output contd…

Log determinant values are within rangeCanonical correlation of 0.780 i.e., this model explains 0.7802 = 60.84% of the variance

Highly significant discriminant function with p value close to zeroF value of 13.272 ; p value close to 0

BUSINESS RESEARCH METHODS 9

SPSS output contd…

Self-concept score is the strongest predictor followed by anxiety score

Non-smokers have a mean of 1.044 and smokers have a mean of -1.483

BUSINESS RESEARCH METHODS 10

SPSS output contd…

Cutoff Score {0.587 * 1.044} + {0.413 * (-1.483)} = 3.49 e-4

If discriminant score > 3.49e-4 then the record belongs to group 2. Else, belongs to group 1

Classification/Confusion/Prediction Matrix

92.2% of the cases correctly classified.

BUSINESS RESEARCH METHODS 11

SPSS output contd…

Discriminant function

-1.998 + 0.028 * Age + 0.085 * Selfcon - 0.099 * Anxiety - 0.006 * Absence

Records classified into groups 1/2 as per the discriminant scores

Unstandardized coefficients

BUSINESS RESEARCH METHODS 12

References1. http://studysites.uk.sagepub.com/burns/website%20material/Chapter%2025%20-%

20Discriminant%20Analysis.pdf2. Business Research Methods 8e, Zikmund, Babin, Carr, Adhikari, Griffin

BUSINESS RESEARCH METHODS 13

THANK YOU