[R] Multiple Conditional Tranformations

Sat Nov 25 04:24:45 CET 2006

Good idea. I'm still getting used to how flexible R is on substitutions
like that! -Bob

-----Original Message-----
From: Leeds, Mark (IED) [mailto:Mark.Leeds at morganstanley.com] 
Sent: Friday, November 24, 2006 10:20 PM
To: Muenchen, Robert A (Bob)
Subject: RE: [R] Multiple Conditional Tranformations

You could set temp<-which(my$gender[my$gender == "f"]) and then temp
will have the female indices and
Then you could just put temp everywhere instead of the statement but I
think that's the best you can do.
Definitely, someone will reply and there may be a shorter way that I am
unaware of.

-----Original Message-----
From: r-help-bounces at stat.math.ethz.ch
[mailto:r-help-bounces at stat.math.ethz.ch] On Behalf Of Muenchen, Robert
A (Bob)
Sent: Friday, November 24, 2006 10:09 PM
To: r-help at stat.math.ethz.ch
Subject: Re: [R] Multiple Conditional Tranformations

Mark,

I finally got that approach to work by spreading the logical condition
everywhere. That gets the lengths to match. Still, I can't help but
think there must be a way to specify the logic once per condition.

Thanks,
Bob

mydata$score1<-numeric(mydata$q1) #just initializing.
mydata$score2<-numeric(mydata$q1)
mydata$score1<-NA
mydata$score2<-NA
mydata

mydata$score1[mydata$gender == "f"]<-  2*mydata$q1[mydata$gender=="f"] +

  mydata$q2[mydata$gender=="f"]
mydata$score2[mydata$gender == "f"]<-2.5*mydata$q1[mydata$gender=="f"] +

  mydata$q2[mydata$gender=="f"]
mydata$score1[mydata$gender == "m"]<-3*mydata$q1[mydata$gender=="m"] +
  mydata$q2[mydata$gender=="m"]
mydata$score2[mydata$gender == "m"]<-3.5*mydata$q1[mydata$gender=="m"] +

  mydata$q2[mydata$gender=="m"]
mydata

=========================================================
Bob Muenchen (pronounced Min'-chen), Manager Statistical Consulting
Center U of TN Office of Information Technology 200 Stokely Management
Center, Knoxville, TN 37996-0520
Voice: (865) 974-5230
FAX: (865) 974-4810
Email: muenchen at utk.edu
Web: http://oit.utk.edu/scc,
News: http://listserv.utk.edu/archives/statnews.html
=========================================================

-----Original Message-----
From: Leeds, Mark (IED) [mailto:Mark.Leeds at morganstanley.com]
Sent: Friday, November 24, 2006 8:45 PM
To: Muenchen, Robert A (Bob)
Subject: RE: [R] Multiple Conditional Tranformations

I'm not sure if I understand your question but I don't think you need
iflelse statements.

myscore<-numeric(q1) ( because I'm not sure how to initialize a list so
initialize a vector with q1 elements )

myscore<-NA ( I think this should set all the values in myscore to NA )
myscore[mydata$gender == f]<-2*mydata$q1 + mydata$q2
myscore[mydata$gender == m]<-3*mydata$q1 + mydata$q2

the above should do what you do in the first part of your code but I
don't know if that was your question ?
also, it does it making myscore a vector because I didn't know how to
initialize a list.
Someone else may goive a better solution. I'm no expert.

-----Original Message-----
From: r-help-bounces at stat.math.ethz.ch
[mailto:r-help-bounces at stat.math.ethz.ch] On Behalf Of Muenchen, Robert
A (Bob)
Sent: Friday, November 24, 2006 8:27 PM
To: r-help at stat.math.ethz.ch
Subject: [R] Multiple Conditional Tranformations

Greetings,

I'm learning R and I'm stuck on a basic concept: how to specify a
logical condition once and then perform multiple transformations under
that condition. The program below is simplified to demonstrate the goal.
Its results are exactly what I want, but I would like to check the
logical state of gender only once and create both (or any number of)
scores at once.

mystring<-

("id,group,gender,q1,q2,q3,q4

01,1,f,2,2,5,4

02,2,f,2,1,4,5

03,1,f,2,2,4,4

04,2,f,1,1,5,5

05,1,m,4,5,4,

06,2,m,5,4,5,5

07,1,m,3,3,4,5

08,2,m,5,5,5,4")

mydata<-read.table(textConnection(mystring),header=TRUE,sep=",",row.name
s="id")

mydata 

#Create score1 so that it differs for males and females:

mydata$score1 <- ifelse( mydata$gender=="f" , 

   (mydata$score1 <- (2*mydata$q1)+mydata$q2),

   ifelse( mydata$gender=="m",

      (mydata$score1 <- (3*mydata$q1)+mydata$q2), NA )

   )

mydata

#Create score2 so that it too differs for males and females:

mydata$score2 <- ifelse( mydata$gender=="f" , 

   (mydata$score2 <- (2.5*mydata$q1)+mydata$q2),

   ifelse( mydata$gender=="m",

      (mydata$score2 <- (3.5*mydata$q1)+mydata$q2), NA )

   )

mydata

Thanks!

Bob

=========================================================
Bob Muenchen (pronounced Min'-chen), Manager Statistical Consulting
Center U of TN Office of Information Technology 200 Stokely Management
Center, Knoxville, TN 37996-0520
Voice: (865) 974-5230
FAX: (865) 974-4810
Email: muenchen at utk.edu
Web: http://oit.utk.edu/scc <http://oit.utk.edu/scc> ,
News: http://listserv.utk.edu/archives/statnews.html
<http://listserv.utk.edu/archives/statnews.html>
=========================================================

	[[alternative HTML version deleted]]

______________________________________________
R-help at stat.math.ethz.ch 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.
--------------------------------------------------------

This is not an offer (or solicitation of an offer) to buy/sell the
securities/instruments mentioned or an official confirmation.  Morgan
Stanley may deal as principal in or own or act as market maker for
securities/instruments mentioned or may advise the issuers.  This is not
research and is not from MS Research but it may refer to a research
analyst/research report.  Unless indicated, these views are the author's
and may differ from those of Morgan Stanley research or others in the
Firm.  We do not represent this is accurate or complete and we may not
update this.  Past performance is not indicative of future returns.  For
additional information, research reports and important disclosures,
contact me or see https://secure.ms.com/servlet/cls.  You should not use
e-mail to request, authorize or effect the purchase or sale of any
security or instrument, to send transfer instructions, or to effect any
other transactions.  We cannot guarantee that any such requests received
via e-mail will be processed in a timely manner.  This communication is
solely for the addressee(s) and may contain confidential information.
We do not waive confidentiality by mistransmission.  Contact me if you
do not wish to receive these communications.  In the UK, this
communication is directed in the UK to those persons who are market
counterparties or intermediate customers (as defined in the UK Financial
Services Authority's rules).

______________________________________________
R-help at stat.math.ethz.ch 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.
--------------------------------------------------------

This is not an offer (or solicitation of an offer) to buy/sell the
securities/instruments mentioned or an official confirmation.  Morgan
Stanley may deal as principal in or own or act as market maker for
securities/instruments mentioned or may advise the issuers.  This is not
research and is not from MS Research but it may refer to a research
analyst/research report.  Unless indicated, these views are the author's
and may differ from those of Morgan Stanley research or others in the
Firm.  We do not represent this is accurate or complete and we may not
update this.  Past performance is not indicative of future returns.  For
additional information, research reports and important disclosures,
contact me or see https://secure.ms.com/servlet/cls.  You should not use
e-mail to request, authorize or effect the purchase or sale of any
security or instrument, to send transfer instructions, or to effect any
other transactions.  We cannot guarantee that any such requests received
via e-mail will be processed in a timely manner.  This communication is
solely for the addressee(s) and may contain confidential information.
We do not waive confidentiality by mistransmission.  Contact me if you
do not wish to receive these communications.  In the UK, this
communication is directed in the UK to those persons who are market
counterparties or intermediate customers (as defined in the UK Financial
Services Authority's rules).