Martin - Of course you are right. The documentation for truehist (and hist) explains that fact nicely, which is why I thought to send him there. Sorry for any confusion.
Thanks, Erik Martin Maechler wrote: >>>>>>"Erik" == Erik Iverson <[EMAIL PROTECTED]> >>>>>> on Thu, 27 Apr 2006 13:44:16 -0500 writes: > > > Erik> See ?truehist in the MASS package. > > Not in this case! > truehist() also computes a density, > and its values on the "y axis" are not probabilities, either! > hist(*, freq = FALSE) > is fully sufficient here -- the problem of the original poster > was to understand that a density can have values larger than 1. > It may be interesting and is somewhat disappointing for us > "teachers of statistics" to see how many people have posted in > the past on this exact topic, sometimes even more or less > assuming that R was doing some things wrongly because it showed > densities (or density estimates as here) with values larger than > one... oh dear > "Mit der Dummheit kaempfen Goetter selbst vergebens." > - Friedrich Schiller, "Die Jungfrau von Orleans" > > Martin > > >> Philipp Pagel wrote: > >> On Thu, Apr 27, 2006 at 10:48:39AM -0700, [EMAIL PROTECTED] > >> wrote: > >> > >>> Hi All, > >>> > >>> I want to use "hist" to get the relative frequency > >>> plot. But the range of ylab is greater than 1,which I > >>> think it should be less than 1 since it stands for the > >>> probability. > >>> > >>> I'm confused. Could you please help me with it? > >> > >> > >> I was pretty confused by that, too at first. The solution > >> is that freq=False cause hist to plot the DENSITY rather > >> than frequency. And density is not necesssarily the same > >> as relative frequency. Excerpt from ?hist: > >> > >> density: values f^(x[i]), as estimated density values. If > >> 'all(diff(breaks) == 1)', they are the relative > >> frequencies 'counts/n' and in general satisfy sum[i; > >> f^(x[i]) (b[i+1]-b[i])] = 1, where b[i] = 'breaks[i]'. > >> > >> If you want relative distance try something like this: > >> > >> myhist = hist(x,breaks=52, plot=F) myhist$counts = > >> myhist$counts / sum(myhist$counts) > >> plot(myhist,main=NULL,border=TRUE,xlab="days",xlim=c(0,6),lty=2) > >> > >> Not exactly clean, though -- we are messing with the > >> myhist object... > >> > >> > >> cu Philipp > >> > > Erik> ______________________________________________ > Erik> R-help@stat.math.ethz.ch mailing list > Erik> https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do > Erik> read the posting guide! > Erik> http://www.R-project.org/posting-guide.html ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html