Brown-Forsythe Issue in ANOVA

Posted by Jarrod Teo-2 on
URL: http://spssx-discussion.165.s1.nabble.com/How-data-entry-for-TURF-analysis-tp4635246p4657430.html

Hi,

I have some queries on Brown-Forsythe.

Query 1

I have an issue with ANOVA. One of my categories is having a 0 variance. Hence SPSS could not calculate the Brown-Forsythe's Statistics. The Levene Statistics showed that the homogeneity of variance was not met and hence F Statistics could not be use. I have checked and found out that the reason why one of my categories is having a 0 variance is because no respondents fell under this category. My instinct is to remove this category and perform an ANOVA again with K-1 categories. Is this a correct approach?

Query 2

My case happened because one category has 0 respondent in it and this caused the 0 variance issue. However I would like to also check if anyone had this similar issue before but under the following condition. (I kind of doubt the possibility of a 0 variance with all the categories ! having at least one respondents though.)

1. All categories have respondents in them.
2. At least one of the categories have 0 variance and caused SPSS unable to calculate Brown-Forsythe's Statistics. 
3. Lastly, the work around for this situation.

Thanks.

Dorraj Oet