Brown-Forsythe test

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Brown-Forsythe test

Salbod

Good Day Friends,

                When should the two options on the one-way procedure:  Brown-Forythe and Welch be checked? I have three groups of data that have unequal ns and unequal variances. I’m planning to use Dunnett C for post-hoc analyses. When I checked Welch procedure, PASW Statistics generated a pivot table labeled: “Robust Tests of Equality of Means”. Does this mean that these are not HOV tests?

 

                Any light you can shine on this issue will be greatly appreciated.

 

Stephen Salbod, Pace University, NYC   

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Re: Brown-Forsythe test

Marta Garcia-Granero
Hi Stephen


Brown-Forsythe and Welch tests are indeed NOT HOV tests. If you want to
check the HOV assumption, use Levene test. Welch test should be used as
a replacement of the ordinary F test of the ANOVA table if HOV
assumption is not met and the design is unbalanced, like in your case.

HTH,
Marta GG

Salbod, Mr. Stephen wrote:

>
> Good Day Friends,
>
> When should the two options on the one-way procedure: Brown-Forythe
> and Welch be checked? I have three groups of data that have unequal ns
> and unequal variances. I’m planning to use Dunnett C for post-hoc
> analyses. When I checked Welch procedure, PASW Statistics generated a
> pivot table labeled: “Robust Tests of Equality of Means”. Does this
> mean that these are not HOV tests?
>
> Any light you can shine on this issue will be greatly appreciated.
>
> Stephen Salbod, Pace University, NYC
>


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