[R] Comparing Points on Two Regression Lines

[AbouEl-Makarim Aboueissa]

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









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AbouEl-Makarim Aboueissa, Ph.D.
Assistant Professor of Statistics
Department of Mathematics & Statistics
University of Southern Maine
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