Why variance so important?
Message posted by Willie on January 18, 2000 at 12:00 AM (ET)

Hi,

I am a beginner in basic research stats.I have been reading a lot of books
but still cannot cpmprehend why does variance determines whether there
is significant difference or not and why must groups have same variance
before they can be compared?

Would be glad if someone can enlighten me on this basic premise.

Thanks.

Willie