[R] anova error

[Ben Bolker]

Peter Ehlers <ehlers <at> ucalgary.ca> writes:

> 
> It might be a good idea not to use an outdated version of R.
> I don't see your "problem" in R 2.12.0.
> 
> Peter Ehlers
> 
> On 2010-12-01 05:44, Jean.Coursol <at> math.u-psud.fr wrote:
> > Just for fun
> >
> > This small program gives negative Sum of Sq in anova (with R versions
> > 2.9.2 and 2.10.0) (linux 32 kernel 2.6.29.6-smp slackware 13.0) :
> >

  These are essentially just round-off error in a problem with zero
noise: there is absolutely no practical difference between 2e-16 and
2e16.  If you really need to do something with these values that will
break if they are negative, see ?zapsmall ...