Message-ID: <49D0F9CD.01BB.00A6.1@usm.maine.edu>
Date: 2009-03-30T20:56:46Z
From: AbouEl-Makarim Aboueissa
Subject: Comparing Points on Two Regression Lines
Dear R users:
Suppose I have two different response variables y1, y2 that I regress separately on the different explanatory variables, x1 and x2 respectively. I need to compare points on two regression lines.
These are the x and y values for each lines.
x1<-c(0.5,1.0,2.5,5.0,10.0)
y1<-c(204,407,1195,27404313)
x2<-c(2.5,5.0,10.0,25.0)
y2<-c(440,713,1520,2634)
Suppose we need to compare the two lines at the common value of x=13.
Please see attached the method as described in section 18.3 in Jerrold H. Zar.
With many thanks
Abou
==========================
AbouEl-Makarim Aboueissa, Ph.D.
Assistant Professor of Statistics
Department of Mathematics & Statistics
University of Southern Maine
96 Falmouth Street
P.O. Box 9300
Portland, ME 04104-9300
Tel: (207) 228-8389
Fax: (207) 780-5607
Email: aaboueissa at usm.maine.edu
aboueiss at yahoo.com
http://www.usm.maine.edu/~aaboueissa/
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