Date:         Wed, 8 Aug 2007 17:10:29 +0100
Reply-To:     Eamonn O'Brien <eamonnjobrien@GMAIL.COM>
Sender:       "SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU>
From:         Eamonn O'Brien <eamonnjobrien@GMAIL.COM>
Subject:      comparing curves
Content-Type: text/plain; charset=ISO-8859-1

I have absorbance data from two samples read once a day for 6 days.
The response is the absorbance for wavelengths ranging from 400 to 800
nm in 1 nm steps. The research question is : Are the two curves ( as
they appear to resemble survival curves in shape) for each sample
statistically different and does the day variable have an effect?
What would be an appropriate analysis in SAS for this type of data?
thanks.


My data is of the form :

data abs;
input nm sample day abs;
datalines;
400     3       1       .1772
400     3       2       .1742
400     3       3       .1792
400     3       4       .1868
400     3       5       .1871
400     3       6       .1858
400     5       1       .1863
400     5       2       .1985
400     5       3       .1937
400     5       4       .1926
400     5       5       .1933
400     5       6       .1932
401     3       1       .1756
401     3       2       .1726
401     3       3       .1775
401     3       4       .1853
401     3       5       .1854
.etc...............