Re: [R] what "density" is plotting ?
?density Or http://en.m.wikipedia.org/wiki/Kernel_density_estimation?wasRedirected=true "Ralf B" wrote: >The density function works empirically based on your data. It makes no >assumption about an underlying distribution. > >Ralf > >On Thu, Jun 24, 2010 at 10:48 PM, Carrie Li wrote: >> Hello, Ralf, >> >> Sorry I was being clear. >> I mean probability density function >> like normal f(x)=(1/2*pi*sd )*exp() something like that . >> Sorry about the confusion >> >> Carrie >> >> On Thu, Jun 24, 2010 at 10:43 PM, Ralf B wrote: >>> >>> Hi Carrie, >>> >>> the output is defined by you; density() only creates the function >>> which you need to plot using the plot() function. When you call >>> plot(density(x)) you get the output on the screen. You need to use >>> pdf() if you want to create a pdf file, png() for creating a png file >>> or postscript if you like ps; there are many others. >>> >>> Ralf >>> >>> On Thu, Jun 24, 2010 at 10:35 PM, Carrie Li >>> wrote: >>> > Hi everyone, >>> > >>> > I am confused regarding the function "density". >>> > suppose that there is a sample x of 100 data points, and >>> > plot(density(x)) >>> > gives it's pdf ? >>> > or it's more like histogram only ? >>> > >>> > thanks for any answering >>> > >>> > Carrie >>> > >>> > [[alternative HTML version deleted]] >>> > >>> > __ >>> > 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. --- Jeff NewmillerThe . . Go Live... DCN:Basics: ##.#. ##.#. Live Go... Live: OO#.. Dead: OO#.. Playing Research Engineer (Solar/BatteriesO.O#. #.O#. with /Software/Embedded Controllers) .OO#. .OO#. rocks...1k --- Sent from my phone. Please excuse my brevity. __ 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.
Re: [R] what "density" is plotting ?
The density function works empirically based on your data. It makes no assumption about an underlying distribution. Ralf On Thu, Jun 24, 2010 at 10:48 PM, Carrie Li wrote: > Hello, Ralf, > > Sorry I was being clear. > I mean probability density function > like normal f(x)=(1/2*pi*sd )*exp() something like that . > Sorry about the confusion > > Carrie > > On Thu, Jun 24, 2010 at 10:43 PM, Ralf B wrote: >> >> Hi Carrie, >> >> the output is defined by you; density() only creates the function >> which you need to plot using the plot() function. When you call >> plot(density(x)) you get the output on the screen. You need to use >> pdf() if you want to create a pdf file, png() for creating a png file >> or postscript if you like ps; there are many others. >> >> Ralf >> >> On Thu, Jun 24, 2010 at 10:35 PM, Carrie Li >> wrote: >> > Hi everyone, >> > >> > I am confused regarding the function "density". >> > suppose that there is a sample x of 100 data points, and >> > plot(density(x)) >> > gives it's pdf ? >> > or it's more like histogram only ? >> > >> > thanks for any answering >> > >> > Carrie >> > >> > [[alternative HTML version deleted]] >> > >> > __ >> > 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.
Re: [R] what "density" is plotting ?
Hello, Ralf, Sorry I was being clear. I mean probability density function like normal f(x)=(1/2*pi*sd )*exp() something like that . Sorry about the confusion Carrie On Thu, Jun 24, 2010 at 10:43 PM, Ralf B wrote: > Hi Carrie, > > the output is defined by you; density() only creates the function > which you need to plot using the plot() function. When you call > plot(density(x)) you get the output on the screen. You need to use > pdf() if you want to create a pdf file, png() for creating a png file > or postscript if you like ps; there are many others. > > Ralf > > On Thu, Jun 24, 2010 at 10:35 PM, Carrie Li > wrote: > > Hi everyone, > > > > I am confused regarding the function "density". > > suppose that there is a sample x of 100 data points, and plot(density(x)) > > gives it's pdf ? > > or it's more like histogram only ? > > > > thanks for any answering > > > > Carrie > > > >[[alternative HTML version deleted]] > > > > __ > > 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. > > > [[alternative HTML version deleted]] __ 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.
Re: [R] what "density" is plotting ?
Hi Carrie, the output is defined by you; density() only creates the function which you need to plot using the plot() function. When you call plot(density(x)) you get the output on the screen. You need to use pdf() if you want to create a pdf file, png() for creating a png file or postscript if you like ps; there are many others. Ralf On Thu, Jun 24, 2010 at 10:35 PM, Carrie Li wrote: > Hi everyone, > > I am confused regarding the function "density". > suppose that there is a sample x of 100 data points, and plot(density(x)) > gives it's pdf ? > or it's more like histogram only ? > > thanks for any answering > > Carrie > > [[alternative HTML version deleted]] > > __ > 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.
