snehamoy when you say "positively skewed" do you mean skewed to the left or to the right. If you calculate the skewness coefficient, postive is skewed to the left with a long tail to the right. If your data is skewed to the right, it is negatively skewed.
For negative skewness, we have had success with subtracting limestone values from the maximum chemically possible Ca content. Then using a lognormal approach. That is take 58(?)-Ca and then take logs. If you have a variance of 140, you didn't take logarithms yet. Your variance should be the same whether you do the linear transform or not, only the logarithmic or other "non-linear" transformation would change the variance. Can you clarify? Isobel http://geoecosse.bizland.com/course_brochure.htm ____________________________________________________________ Yahoo! Messenger - Communicate instantly..."Ping" your friends today! Download Messenger Now http://uk.messenger.yahoo.com/download/index.html
