The lines() command doesn't work and histogram combines categories unless you specify the number. How about a barplot
Lam <- 3 X <- table(rpois(500, Lam)) Max <- length(X)-1 barplot(rbind(X, 500*dpois(0:Max, Lam)), beside=TRUE, legend.text=c("Observed", "Expected")) or a rootogram library(vcd) rootogram(X, dpois(0:Max, Lam)*500) -----Original Message----- From: r-help-boun...@r-project.org [mailto:r-help-boun...@r-project.org] On Behalf Of R. Michael Weylandt <michael.weyla...@gmail.com> Sent: Thursday, November 03, 2011 2:55 PM To: kerry1912 Cc: r-help@r-project.org Subject: Re: [R] Histograms in R Try something like this Lam <- 3 X <- rpois(500, Lam) hist(X, freq = F) x <- seq(min(X), max(X), length = 500) lines(x, dpois(x, Lam), col=2) Adapt as necessary Michael On Nov 3, 2011, at 8:03 AM, kerry1912 <kerry1...@hotmail.com> wrote: > We have a histogram of our observed response and we want to overlay the > corresponding poisson distribution with respect to our poisson model. > > > -- > View this message in context: http://r.789695.n4.nabble.com/Histograms-in-R-tp3985397p3985397.html > Sent from the R help mailing list archive at Nabble.com. > > ______________________________________________ > R-help@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code. ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.