|Date: ||Thu, 4 Feb 2010 18:21:46 -0600|
|Reply-To: ||Bhupinder Farmaha <bhupi80singh@YAHOO.CO.IN>|
|Sender: ||"SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU>|
|From: ||Bhupinder Farmaha <bhupi80singh@YAHOO.CO.IN>|
|Subject: ||Normality problem|
|Content-Type: ||text/plain; charset="us-ascii"|
I need your suggestion about appropriate measure to tackle non-normal data.
I ran an agronomic experiment for three years. I am modeling it using Proc
Mixed. I found that data do not meet the assumption of normality. The
problem I found that response variables values are quite different for one
year compared to other two years. The part of the reason it is weather
driven. I have tried log transformation but it didn't work at all. I don't
know if I have to give less weights to data from that year or what can be
the other approach. It is clear from the some of the preliminary that data
have this problem because crop is adversely affected in one particular years
compared to others.
I would appreciate any feedback on this.