[R] If else

Val valkremk at gmail.com
Sat Oct 31 21:27:55 CET 2015


Thank you very much Ted  for expressing my feeling!. I am working on field
data and the sex of an individual is not recorded  sometimes and hence and
I give it  a category of  NA.

Thank you all for the help.




On Sat, Oct 31, 2015 at 2:47 PM, Ted Harding <Ted.Harding at wlandres.net>
wrote:

> [Apologies if the message below should arrive twice. When first
> sent there was apparently something wrong with the email address
> to r-help, and it was held for moderation because "Message has
> implicit destination" (whatever that means). I have made sure
> that this time the email address is correct.]
>
> John Fox has given a neat expression to achieve the desired result!
>
> I would like to comment, however, on the somewhat insistent criticism
> of Val's request from several people.
>
> It can make sense to have three "sex"es. Suppose, for example,
> that the data are records of street crime reported by victims.
> The victim may be able to identify the sex of the preprator
> as definitely "M", or definitely "F". One of the aims of the
> analysis is to investgate whether there is an association
> between the gender of the offender and the type of crime.
>
> But in some cases the victim may not have been able to recognise
> the offender's sex. Then it would have to go in the record as "NA"
> (or equivalent). There can be two kinds of reason why the victim
> was unable to recognise the sex. One kind is where the victim
> simply did not see the offender (e.g. their purse was stolen
> while they were concentrating on something else, and they only
> found out later). Another kind is where the offender deliberately
> disguises their gender, so that it cannot be determined from their
> appearance. This second kind could be associated with a particular
> category of crime (and I leave it to people's lurid imaginations
> to think of possible examples ... ).
>
> Then one indeed has three "sex"es: Male, Female, and Indeterminate,
> for each of which there is a potential assoctiation with type of crime.
> With most analyses, however, a category of "NA" would be ignored
> (at least by R).
>
> And then one has a variable which is a factor with 3 levels, all
> of which can (as above) be meaningful), and "NA" would not be
> ignored.
>
> Hoping this helps to clarify! (And, Val, does the above somehow
> correspond to your objectives).
>
> Best wishes to all,
> Ted.
>
> On 31-Oct-2015 17:41:02 Jeff Newmiller wrote:
> > Rolf gave you two ways. There are others. They all misrepresent the data
> > (there are only two sexes but you are effectively acting as if there are
> > three); hence the inquisition in hopes of diverting you to a more correct
> > method of analysis. However, this is not the support forum for whatever
> other
> > software you plan to proceed with so never mind.
> >
> ---------------------------------------------------------------------------
> > Jeff Newmiller                        The     .....       .....  Go
> Live...
> > DCN:<jdnewmil at dcn.davis.ca.us>        Basics: ##.#.       ##.#.  Live
> Go...
> >                                       Live:   OO#.. Dead: OO#..  Playing
> > Research Engineer (Solar/Batteries            O.O#.       #.O#.  with
> > /Software/Embedded Controllers)               .OO#.       .OO#.
> rocks...1k
> >
> ---------------------------------------------------------------------------
> > Sent from my phone. Please excuse my brevity.
> >
> > On October 31, 2015 10:15:33 AM PDT, Val <valkremk at gmail.com> wrote:
> >>Hi Jeff,
> >>
> >>I thought I answered. Yes I was not clear about it.  The further
> >>analysis
> >>will no  be done by R.  It is another software that will not accept a
> >>character response variable.
> >>
> >>Why R is so complicated to do that.  If it is SAS then I can do it on
> >>one
> >>statement. .
> >>
> >>
> >>On Sat, Oct 31, 2015 at 11:39 AM, Jeff Newmiller
> >><jdnewmil at dcn.davis.ca.us>
> >>wrote:
> >>
> >>> You haven't actually answered John's question as to the type of
> >>analysis
> >>> you plan to do. It still looks from here like you should be using
> >>factor
> >>> data rather than numeric, but since you are not being clear we cannot
> >>give
> >>> specifics as to how to proceed.
> >>>
>
> >>---------------------------------------------------------------------------
> >>> Jeff Newmiller                        The     .....       .....  Go
> >>Live...
> >>> DCN:<jdnewmil at dcn.davis.ca.us>        Basics: ##.#.       ##.#.  Live
> >>> Go...
> >>>                                       Live:   OO#.. Dead: OO#..
> >>Playing
> >>> Research Engineer (Solar/Batteries            O.O#.       #.O#.  with
> >>> /Software/Embedded Controllers)               .OO#.       .OO#.
> >>rocks...1k
> >>>
>
> >>---------------------------------------------------------------------------
> >>> Sent from my phone. Please excuse my brevity.
> >>>
> >>> On October 31, 2015 8:23:05 AM PDT, Val <valkremk at gmail.com> wrote:
> >>> >Hi All,
> >>> >
> >>> >
> >>> >Yes I need  to change to numeric  because I am preparing a data set
> >>> >for
> >>> >further  analysis. The variable to be changed  from character to
> >>> >numeric
> >>> >(in this case, sex) will be a response variable.  Some records have
> >>> >missing
> >>> >observation on sex and it is blank.
> >>> >     id  sex
> >>> >      1
> >>> >      2
> >>> >      3  M
> >>> >      4  F
> >>> >      5  M
> >>> >      6  F
> >>> >      7  F
> >>> >
> >>> >I am reading the data like this
> >>> >
> >>> >mydata <- read.csv(header=TRUE, text=', sep=", ")
> >>> >     id  sex
> >>> >      1   NA
> >>> >      2  NA
> >>> >      3  M
> >>> >      4  F
> >>> >      5  M
> >>> >      6  F
> >>> >      7  F
> >>> >
> >>> >The  data set is huge   (>250,000)
> >>> >
> >>> >
> >>> >I want the output like this
> >>> >
> >>> >     id  sex    sex1
> >>> >      1   NA    0
> >>> >      2  NA     0
> >>> >      3  M       1
> >>> >      4  F       2
> >>> >      5  M      1
> >>> >      6  F       2
> >>> >      7  F       2
> >>> >
> >>> >Thank you in advance
> >>> >
> >>> >
> >>> >On Sat, Oct 31, 2015 at 5:59 AM, John Kane <jrkrideau at inbox.com>
> >>wrote:
> >>> >
> >>> >> In line.
> >>> >>
> >>> >> John Kane
> >>> >> Kingston ON Canada
> >>> >>
> >>> >>
> >>> >> > -----Original Message-----
> >>> >> > From: valkremk at gmail.com
> >>> >> > Sent: Fri, 30 Oct 2015 20:40:03 -0500
> >>> >> > To: istazahn at gmail.com
> >>> >> > Subject: Re: [R] If else
> >>> >> >
> >>> >> > I am trying to change the mydata$sex  from character to numeric
> >>> >>
> >>> >> Why?
> >>> >>  As Ista (mydata$confusingWillCauseProblemsLater) has pointed out
> >>> >this is
> >>> >> a very unusual thing to do in R.
> >>> >>
> >>> >> Is there a very specific reason for doing this in your analysis.
> >>> >> Otherwise it may better to leave the coding as NA. Some of the
> >>data
> >>> >mungers
> >>> >> here may be able to suggest which is the best strategy in R.
> >>> >>
> >>> >> R is 'weird' compared to more mundane stats packages such as SAS
> >>or
> >>> >SPSS
> >>> >> and common techniques that one would use with them often are not
> >>> >> appropriate in R.
> >>> >>
> >>> >>
> >>> >>
> >>> >>
> >>> >> > I want teh out put like
> >>> >> >    id  sex
> >>> >> >       1  NA   0
> >>> >> >       2  NA   0
> >>> >> >       3  M     1
> >>> >> >       4  F     2
> >>> >> >       5  M    1
> >>> >> >       6  F     2
> >>> >> >       7  F    2
> >>> >> >
> >>> >> > mydata$sex1 <- 0
> >>> >> > if(mydata$sex =="M " ){
> >>> >> >   mydata$sex1<-1
> >>> >> > } else {
> >>> >> >   mydata$sex1<-2
> >>> >> > }
> >>> >> >
> >>> >> > mydata$sex1
> >>> >> >
> >>> >> > Warning message:In if (mydata$sex == "M ") { :
> >>> >> >   the condition has length > 1 and only the first element will
> >>be
> >>> >> > used> mydata$sex1[1] 2 2 2 2 2 2 2 2
> >>> >> >
> >>> >> >>
> >>> >> >
> >>> >> >
> >>> >> > On Fri, Oct 30, 2015 at 8:28 PM, Ista Zahn <istazahn at gmail.com>
> >>> >wrote:
> >>> >> >
> >>> >> >> Using numeric for missing sounds like asking for trouble. But
> >>if
> >>> >you
> >>> >> >> must, something like
> >>> >> >>
> >>> >> >> mydata$confusingWillCauseProblemsLater <-
> >>> >> >>   ifelse(
> >>> >> >>     is.na(mydata$sex),
> >>> >> >>     0,
> >>> >> >>     as.numeric(factor(mydata$sex,
> >>> >> >>                       levels = c("M", "F"))))
> >>> >> >>
> >>> >> >> should do it.
> >>> >> >>
> >>> >> >> Best,
> >>> >> >> Ista
> >>> >> >>
> >>> >> >> On Fri, Oct 30, 2015 at 9:15 PM, Val <valkremk at gmail.com>
> >>wrote:
> >>> >> >>> Hi all,
> >>> >> >>> Iam trying to change character  to numeric but have probelm
> >>> >> >>>
> >>> >> >>> mydata <- read.table(header=TRUE, text=', sep=" "
> >>> >> >>>      id  sex
> >>> >> >>>       1  NA
> >>> >> >>>       2  NA
> >>> >> >>>       3  M
> >>> >> >>>       4  F
> >>> >> >>>       5  M
> >>> >> >>>       6  F
> >>> >> >>>       7  F
> >>> >> >>>        ')
> >>> >> >>>
> >>> >> >>> if sex is missing then sex=0;
> >>> >> >>> if sex is"M" then sex=1;
> >>> >> >>> if sex is"F" then sex=2;
> >>> >> >>>
> >>> >> >>> Any help please ?
> >>> >> >>>
> >>> >> >>>         [[alternative HTML version deleted]]
> >>> >> >>>
> >>> >> >>> ______________________________________________
> >>> >> >>> R-help at r-project.org mailing list -- To UNSUBSCRIBE and more,
> >>see
> >>> >> >>> 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 at r-project.org mailing list -- To UNSUBSCRIBE and more,
> >>see
> >>> >> > 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.
> >>> >>
> >>> >> ____________________________________________________________
> >>> >> FREE 3D MARINE AQUARIUM SCREENSAVER - Watch dolphins, sharks &
> >>orcas
> >>> >on
> >>> >> your desktop!
> >>> >> Check it out at http://www.inbox.com/marineaquarium
> >>> >>
> >>> >>
> >>> >>
> >>> >
> >>> >       [[alternative HTML version deleted]]
> >>> >
> >>> >______________________________________________
> >>> >R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see
> >>> >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 -- To UNSUBSCRIBE and more, see
> > 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.
>
> -------------------------------------------------
> E-Mail: (Ted Harding) <Ted.Harding at wlandres.net>
> Date: 31-Oct-2015  Time: 19:29:50
> This message was sent by XFMail
> -------------------------------------------------
>

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