[R] boxplot statistics

[Karin Lagesen]

I have read and reread the boxplot and the boxplot stats page, and I
still cannot understand how and what boxplot shows. I realize that
this might be due to me not knowing enough statistics, but anyway...

First, how does boxplot determine the size of the box? And is the line
inside the box the mean or the median (or something completely
different?) And how does it determine how long out the whiskers should
go?

Also, the boxplot.stats page talks about "hinges", what are those?  
"The two "hinges" are versions of the first and third quartile, i.e.,
close to 'quantile(x, c(1,3)/4)'."

Thankyou very much.

Karin
-- 
Karin Lagesen, PhD student
karin.lagesen at medisin.uio.no
http://www.cmbn.no/rognes/