[R] Insert regression coefficients in a graphic.

[David Winsemius]

On Apr 22, 2011, at 2:16 PM, JJCV wrote:

> Hello.
>
> I did a graphic with the next code:
>
> T=c(10,15,20,25,30)
> p=c(1003,1005,1010,1011,1014)
> plot(T, p, xlab=" ",, ylab=" ", pch=1, cex=2, lwd=2,
> xlim=c(5,30), ylim=c(1000,1015))
> abline(lm(p ~ T), lwd=2)
> lm(p ~ T)
>
> I want to see the regression coefficient in the graphic. ¿How can I  
> do that?

 > coef(lm(p ~ T)
+ )
(Intercept)           T
      997.40        0.56
 > text(10,1010, labels=paste("Slope =", coef(lm(p ~ T)  )[2]) )

I suppose you could format it with formatC() or sprintf() if you  
wanted it to fewer than 10 decimal places.


-- 
David Winsemius, MD
West Hartford, CT