[R] Cook-distance-type plot (vertical bars)
Prof Brian Ripley
ripley at stats.ox.ac.uk
Thu Aug 28 19:13:26 CEST 2003
On Thu, 28 Aug 2003, Frank Gibbons wrote:
> Hi,
>
> Figure 13 of Emmanuel Paradis's "R for Beginners" was produced by termplot
> working on an aov object. The lower right-hand plot is labelled "Cook's
> distance plot", and I'd really like to produce a similar type of figure,
> but in a totally different context. (I'm not even sure what this kind of
> figure is called, perhaps an "impulse plot", where instead of a point at
> (x,y), there's a vertical bar running from the x-axis up to where the point
> would be).
Often called an `index plot'. It's done by plot(type="h"). R seems to
think that is `histogram-like', but the notation comes from S which calls
it `high-density lines'. I've never found either intuitive notation.
> Can anyone give me pointers on where to look for more info. I've had a look
> in the places I could think of (plot.lm.R, termplot.R, plot.R, aov.R), and
> couldn't find anything. Maybe I overlooked it?
I suspect it was done by plot.lm(which=4), which does an index plot of
Cook's distance.
--
Brian D. Ripley, ripley at stats.ox.ac.uk
Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/
University of Oxford, Tel: +44 1865 272861 (self)
1 South Parks Road, +44 1865 272866 (PA)
Oxford OX1 3TG, UK Fax: +44 1865 272595
More information about the R-help
mailing list