Re: [R] How to calculate normality of the residuals from a test in R?

From: Gavin Simpson <>
Date: Thu, 07 Feb 2008 12:05:44 +0000

hits=-2.6 tests=BAYES_00
X-USF-Spam-Flag: NO

On Thu, 2008-02-07 at 11:56 +0100, Falco tinnunculus wrote:
> Hi,
> How do I calculate normality distribution of the residuals from a test in R?
> I have tried plot(mod1), and I get a nice plot, but no p-value... is there
> some other ways to calculate this?
> Regards Kes,

You could use a QQ-plot to judge normality of residuals.

x <- runif(100)
y <- 3 + (0.8 * x) + rnorm(100, mean = 0, sd = 0.5) mod <- lm(y ~ x)

mod.resi <- resid(mod)

Systematic deviations from the line, indicate departures from normality (in this case), such as heavy tails, skewness. If the residuals were normally distributed they should be scattered around the line.


 Dr. Gavin Simpson             [t] +44 (0)20 7679 0522
 ECRC, UCL Geography,          [f] +44 (0)20 7679 0565
 Pearson Building,             [e]
 Gower Street, London          [w]
 UK. WC1E 6BT.                 [w]

______________________________________________ mailing list
PLEASE do read the posting guide
and provide commented, minimal, self-contained, reproducible code.
Received on Thu 07 Feb 2008 - 12:09:32 GMT

Archive maintained by Robert King, hosted by the discipline of statistics at the University of Newcastle, Australia.
Archive generated by hypermail 2.2.0, at Thu 07 Feb 2008 - 12:30:12 GMT.

Mailing list information is available at Please read the posting guide before posting to the list.

list of date sections of archive