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Levene's Test In SAS and SPSS

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Occasional Contributor
Posts: 7

Levene's Test In SAS and SPSS

Hi,

Has anyone encountered this - different Levene's test result for homogeneity of variance between SAS and SPSS?

 

Below is the results in SAS and after that SPSS. Everything else is the same excep the levene's test. Do you know why that may be?Thank you in advance.

 

SAS

Levene's Test for Homogeneity of Q4_CodedCount Variance ANOVA of Squared Deviations from Group Means

Source

DF

Sum of Squares

Mean Square

F Value

Pr > F

Condition

2

1.1994

0.5997

1.05

0.3493

Error

1409

802.6

0.5696

 

 

 

Source

DF

Sum of Squares

Mean Square

F Value

Pr > F

Model

2

4.5688012

2.2844006

4.35

0.0131

Error

1409

739.7109438

0.5249900

 

 

Corrected Total

1411

744.2797450

 

 

 

 

 

 

 

SPSS

Test of Homogeneity of Variances

Q4_CodedCount Count of correct benefits recalled

Levene Statistic

df1

df2

Sig.

8.768

2

1409

.000

 

ANOVA

Q4_CodedCount Count of correct benefits recalled

 

Sum of Squares

df

Mean Square

F

Sig.

Between Groups

4.569

2

2.284

4.351

.013

Within Groups

739.711

1409

.525

  

Total

744.280

1411

   
Super User
Posts: 10,500

Re: Levene's Test In SAS and SPSS

Without knowing the options used between the two, i.e. program code, it is difficult to point towards specific possibilities.

The documentation shows that the SAS default in Proc Anova for HOVTEST=Levene defaults to using squared residuals (Type=Square).

I don't know about SPSS but that seems like something easy to investigate whether SPSS defaults to absolute residuals.

Super User
Posts: 17,829

Re: Levene's Test In SAS and SPSS

Or you could switch SAS to abs to check:

 

hovtest=levene(type=abs)
Occasional Contributor
Posts: 7

Re: Levene's Test In SAS and SPSS

Thank you both for your comments. That is exactly what is happening, SPSS uses absolute and SAS uses squared by default. Thank you.

Super User
Posts: 17,829

Re: Levene's Test In SAS and SPSS

@mmjohnson Please mark the question answered Smiley Happy

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