homogeneity of variance, for a section of my thesis on sex differences

in variability of cognitive performance (greater male variability hypothesis). As I don't

have the original data I'm analysing, I can't use SPSS to calculate Levene's for me, and

need to calculate it manually (ideally in Excel!).

I've come across this resource on the calculation of Levene's (http://www.itl.nist.gov/div898/handbook/eda/section3/eda35a.htm) which gives the original formula as thus:

where Zij can have one of the following three definitions:

1.

where Yi is the mean of the ith subgroup.

1.

where Yi is the mean of the ith subgroup.

What I can't understand (and may be on completely the wrong track about) is where the actual standard deviation of the groups comes in ..... because male and female scores often have the

**same**or negligible mean differences, but different standard deviations (and hence variance).

Can anyone point me to a worked example of a Levene's test, or explain it to me

simply? All I want to do is see if the SD1 != SD2 (hypothesis supported) or if SD1 = SD2 (hypothesis not supported).

Many thanks and eternal grattiude for your help!