[R] how to remove outliers

[S Ellison]

The outlier is a maximum value, so which.max() is likely to be useful 

time <- time[-which.max(time$TimeDiff ),]

should work reliably.


S Ellison

> -----Original Message-----
> From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-project.org]
> On Behalf Of Bert Gunter
> Sent: 15 July 2014 11:38
> To: Hasan Diwan
> Cc: R Project Help
> Subject: Re: [R] how to remove outliers
> 
> No! Do not do this.
> 
> First, the syntax is wrong. Second, this will fail in general due to floating point
> arithmetic. Use inequality with sufficient fuzz instead.
> 
> e.g.
> time <- time[time$TimeDiff < 14478,]
> 
> Moral: Caveat Emptor. Free advice may be worth exactly that.
> 
> Cheers,
> Bert
> 
> Bert Gunter
> Genentech Nonclinical Biostatistics
> (650) 467-7374
> 
> "Data is not information. Information is not knowledge. And knowledge is
> certainly not wisdom."
> Clifford Stoll
> 
> 
> 
> 
> On Mon, Jul 14, 2014 at 9:43 PM, Hasan Diwan <hasan.diwan at gmail.com>
> wrote:
> > Marta,
> > To remove a row from your data frame, use:
> >
> > value <- 14478.4
> > time <- time[-time[$TimeDiff] == value,]
> >
> > I hope that helps... If not, do push back. -- H
> >
> >
> > On 14 July 2014 09:17, Marta valdes lopez <martavaldes85 at gmail.com>
> wrote:
> >
> >> Hi!
> >>
> >> I did this test and I got this outlier that i would like to remove
> >> the whole row in my database; anyone knows how i can remove it?
> >>
> >>  chisq.out.test(time$TimeDiff)
> >>         chi-squared test for outlier
> >> data:  time$TimeDiff
> >> X-squared = 73260.07, p-value < 2.2e-16 alternative hypothesis:
> >> highest value 14478.4 is an outlier
> >>
> >> Thank you!!
> >>
> >>         [[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.
> >>
> >
> >
> >
> > --
> > Sent from my mobile device
> > Envoyé de mon portable
> >
> >         [[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.
> >
> 
> ______________________________________________
> 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.


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