R help - Oct 2012 - calculating probability from the density function

Hello,
I have a data x with normal (or very close to normal) distribution, I can
plot a density distribution with density(x,...). My question is is there
any way to calculate an area under this distribution (=probability) for
particular range of x values, let's say for x from 0 to 2? I was not able
to find any kind of simple procedure to do this.
Thanks in advance for your help,
Evgeny.

	[[alternative HTML version deleted]]

Forget density(). Smooth the ecdf instead.

?lowess
?smooth.spline
?monotone.smooth (in package fda, for monotone smoothing, which may be
preferable)
?locfit (in package locfit)

... and many many others

-- Bert

On Mon, Oct 1, 2012 at 6:46 AM, Eugene Kanshin <kanshined1 at gmail.com>
wrote:
> Hello,
> I have a data x with normal (or very close to normal) distribution, I can
> plot a density distribution with density(x,...). My question is is there
> any way to calculate an area under this distribution (=probability) for
> particular range of x values, let's say for x from 0 to 2? I was not
able
> to find any kind of simple procedure to do this.
> Thanks in advance for your help,
> Evgeny.
>
>         [[alternative HTML version deleted]]
>
> ______________________________________________
> R-help at 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.


-- 

Bert Gunter
Genentech Nonclinical Biostatistics

Internal Contact Info:
Phone: 467-7374
Website:
http://pharmadevelopment.roche.com/index/pdb/pdb-functional-groups/pdb-biostatistics/pdb-ncb-home.htm

On Oct 1, 2012, at 6:46 AM, Eugene Kanshin wrote:
> Hello,
> I have a data x with normal (or very close to normal) distribution, I can
> plot a density distribution with density(x,...). My question is is there
> any way to calculate an area under this distribution (=probability) for
> particular range of x values, let's say for x from 0 to 2? I was not
able
> to find any kind of simple procedure to do this.
? pnorm

-- 

David Winsemius, MD
Alameda, CA, USA

You may find it easier to use the logspline density fits (logspline
package) rather than the kernel density estimators for this.

On Mon, Oct 1, 2012 at 7:46 AM, Eugene Kanshin <kanshined1 at gmail.com>
wrote:
> Hello,
> I have a data x with normal (or very close to normal) distribution, I can
> plot a density distribution with density(x,...). My question is is there
> any way to calculate an area under this distribution (=probability) for
> particular range of x values, let's say for x from 0 to 2? I was not
able
> to find any kind of simple procedure to do this.
> Thanks in advance for your help,
> Evgeny.
>
>         [[alternative HTML version deleted]]
>
> ______________________________________________
> R-help at 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.


-- 
Gregory (Greg) L. Snow Ph.D.
538280 at gmail.com