[R] (no subject)

[Sarah Goslee]

Hi,

On Fri, Jun 24, 2011 at 3:15 AM, Ungku Akashah <kaslah90 at yahoo.com> wrote:
> hi dear R crew.
> may i request the script for volcano plot.
> if able, pls include any tips about volcano plot.

Sure. What do you think a volcano plot looks like, and what kind of
data do you wish to use in constructing one?

The R Graph Gallery is a wonderful resource for this sort of question:
http://addictedtor.free.fr/graphiques/
but all the volcano plots listed there are of Maunga Whau, and somehow
I don't think that's what you have in mind.

You probably mean this, don't you?
http://en.wikipedia.org/wiki/Volcano_plot_%28statistics%29

That looks fairly straightforward: use your desired statistical test
on a whole pile of data, extract the p-values, plot their negative
log.

You need to pick the text, but you might be interested in such things
as lm(), t.test(), aov().

Plotting could be done with plot(). log10() might also be useful.

You could browse the R Graph Gallery and see whether anyone has
provided an example under a different name. All of those graphs come
with sample code that you can adapt for your own purposes.

Sarah

-- 
Sarah Goslee
http://www.functionaldiversity.org