[R] Computing growth rate

PIKAL Petr petr.pikal at precheza.cz
Thu Dec 15 14:51:16 CET 2016


Hi

Maybe you does not need if or ifelse but just divide by years difference.

d2<-ddply(df1,"co_code1",transform, growth=c(NA,exp(diff(log(sales1))/diff(fyear1))- 1)*100)

Cheers
Petr

> -----Original Message-----
> From: R-help [mailto:r-help-bounces at r-project.org] On Behalf Of Berend
> Hasselman
> Sent: Thursday, December 15, 2016 1:18 PM
> To: Brijesh Mishra <brijeshkmishra at gmail.com>
> Cc: r-help mailing list <r-help at r-project.org>
> Subject: Re: [R] Computing growth rate
>
>
> > On 15 Dec 2016, at 04:40, Brijesh Mishra <brijeshkmishra at gmail.com>
> wrote:
> >
> > Hi,
> >
> > I am trying to calculate growth rate (say, sales, though it is to be
> > computed for many variables) in a panel data set. Problem is that I
> > have missing data for many firms for many years. To put it simply, I
> > have created this short dataframe (original df id much bigger)
> >
> > df1<-data.frame(co_code1=rep(c(1100, 1200, 1300), each=7),
> > fyear1=rep(1990:1996, 3), sales1=rep(seq(1000,1600, by=100),3))
> >
> > # this gives me
> > co_code1 fyear1 sales1
> > 1      1100   1990   1000
> > 2      1100   1991   1100
> > 3      1100   1992   1200
> > 4      1100   1993   1300
> > 5      1100   1994   1400
> > 6      1100   1995   1500
> > 7      1100   1996   1600
> > 8      1200   1990   1000
> > 9      1200   1991   1100
> > 10     1200   1992   1200
> > 11     1200   1993   1300
> > 12     1200   1994   1400
> > 13     1200   1995   1500
> > 14     1200   1996   1600
> > 15     1300   1990   1000
> > 16     1300   1991   1100
> > 17     1300   1992   1200
> > 18     1300   1993   1300
> > 19     1300   1994   1400
> > 20     1300   1995   1500
> > 21     1300   1996   1600
> >
> > # I am now removing a couple of rows
> > df1<-df1[-c(5, 8), ]
> > # the result is
> >   co_code1 fyear1 sales1
> > 1      1100   1990   1000
> > 2      1100   1991   1100
> > 3      1100   1992   1200
> > 4      1100   1993   1300
> > 6      1100   1995   1500
> > 7      1100   1996   1600
> > 9      1200   1991   1100
> > 10     1200   1992   1200
> > 11     1200   1993   1300
> > 12     1200   1994   1400
> > 13     1200   1995   1500
> > 14     1200   1996   1600
> > 15     1300   1990   1000
> > 16     1300   1991   1100
> > 17     1300   1992   1200
> > 18     1300   1993   1300
> > 19     1300   1994   1400
> > 20     1300   1995   1500
> > 21     1300   1996   1600
> > # so 1994 for co_code1 1100 and 1990 for co_code1 1200 have been
> > removed. If I try,
> > d<-ddply(df1,"co_code1",transform, growth=c(NA,exp(diff(log(sales1)))-
> 1)*100)
> >
> > # this apparently gives wrong results for the year 1995 (as shown
> > below) as growth rates are computed considering yearly increment.
> >
> >   co_code1 fyear1 sales1    growth
> > 1      1100   1990   1000        NA
> > 2      1100   1991   1100 10.000000
> > 3      1100   1992   1200  9.090909
> > 4      1100   1993   1300  8.333333
> > 5      1100   1995   1500 15.384615
> > 6      1100   1996   1600  6.666667
> > 7      1200   1991   1100        NA
> > 8      1200   1992   1200  9.090909
> > 9      1200   1993   1300  8.333333
> > 10     1200   1994   1400  7.692308
> > 11     1200   1995   1500  7.142857
> > 12     1200   1996   1600  6.666667
> > 13     1300   1990   1000        NA
> > 14     1300   1991   1100 10.000000
> > 15     1300   1992   1200  9.090909
> > 16     1300   1993   1300  8.333333
> > 17     1300   1994   1400  7.692308
> > 18     1300   1995   1500  7.142857
> > 19     1300   1996   1600  6.666667
> > # I thought of using the formula only when the increment of fyear1 is
> > only 1 while in a co_code1, by using this formula
> >
> > d<-ddply(df1,
> >         "co_code1",
> >         transform,
> >         if(diff(fyear1)==1){
> >           growth=(exp(diff(log(df1$sales1)))-1)*100
> >         } else{
> >           growth=NA
> >         })
> >
> > But, this doesn't work. I am getting the following error.
> >
> > In if (diff(fyear1) == 1) { :
> >  the condition has length > 1 and only the first element will be used
> > (repeated a few times).
> >
> > # I have searched for a solution, but somehow couldn't get one. Hope
> > that some kind soul will guide me here.
> >
>
> In your case use ifelse() as explained by Rui.
> But it can be done more easily since the fyear1 and co_code1 are
> synchronized.
> Add a new column to df1 like this
>
> df1$growth <- c(NA,
>          ifelse(diff(df1$fyear1)==1,
>                     (exp(diff(log(df1$sales1)))-1)*100,
>                     NA
>                     )
>         )
>
> and display df1. From your request I cannot determine if this is what you
> want.
>
> regards,
>
> Berend Hasselman
>
> ______________________________________________
> 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.

________________________________
Tento e-mail a jakékoliv k němu připojené dokumenty jsou důvěrné a jsou určeny pouze jeho adresátům.
Jestliže jste obdržel(a) tento e-mail omylem, informujte laskavě neprodleně jeho odesílatele. Obsah tohoto emailu i s přílohami a jeho kopie vymažte ze svého systému.
Nejste-li zamýšleným adresátem tohoto emailu, nejste oprávněni tento email jakkoliv užívat, rozšiřovat, kopírovat či zveřejňovat.
Odesílatel e-mailu neodpovídá za eventuální škodu způsobenou modifikacemi či zpožděním přenosu e-mailu.

V případě, že je tento e-mail součástí obchodního jednání:
- vyhrazuje si odesílatel právo ukončit kdykoliv jednání o uzavření smlouvy, a to z jakéhokoliv důvodu i bez uvedení důvodu.
- a obsahuje-li nabídku, je adresát oprávněn nabídku bezodkladně přijmout; Odesílatel tohoto e-mailu (nabídky) vylučuje přijetí nabídky ze strany příjemce s dodatkem či odchylkou.
- trvá odesílatel na tom, že příslušná smlouva je uzavřena teprve výslovným dosažením shody na všech jejích náležitostech.
- odesílatel tohoto emailu informuje, že není oprávněn uzavírat za společnost žádné smlouvy s výjimkou případů, kdy k tomu byl písemně zmocněn nebo písemně pověřen a takové pověření nebo plná moc byly adresátovi tohoto emailu případně osobě, kterou adresát zastupuje, předloženy nebo jejich existence je adresátovi či osobě jím zastoupené známá.

This e-mail and any documents attached to it may be confidential and are intended only for its intended recipients.
If you received this e-mail by mistake, please immediately inform its sender. Delete the contents of this e-mail with all attachments and its copies from your system.
If you are not the intended recipient of this e-mail, you are not authorized to use, disseminate, copy or disclose this e-mail in any manner.
The sender of this e-mail shall not be liable for any possible damage caused by modifications of the e-mail or by delay with transfer of the email.

In case that this e-mail forms part of business dealings:
- the sender reserves the right to end negotiations about entering into a contract in any time, for any reason, and without stating any reasoning.
- if the e-mail contains an offer, the recipient is entitled to immediately accept such offer; The sender of this e-mail (offer) excludes any acceptance of the offer on the part of the recipient containing any amendment or variation.
- the sender insists on that the respective contract is concluded only upon an express mutual agreement on all its aspects.
- the sender of this e-mail informs that he/she is not authorized to enter into any contracts on behalf of the company except for cases in which he/she is expressly authorized to do so in writing, and such authorization or power of attorney is submitted to the recipient or the person represented by the recipient, or the existence of such authorization is known to the recipient of the person represented by the recipient.


More information about the R-help mailing list