[R] Joining two datasets - recursive procedure?

Luca Meyer lucam1968 at gmail.com
Sat Mar 21 14:49:26 CET 2015


Hi Bert,

Thank you for your message. I am looking into ave() and tapply() as you
suggested but at the same time I have prepared a example of input and
output files, just in case you or someone else would like to make an
attempt to generate a code that goes from input to output.

Please see below or download it from
https://www.dropbox.com/s/qhmpkkrejjkpbkx/sample_code.txt?dl=0

# this is (an extract of) the INPUT file I have:
f1 <- structure(list(v1 = c("A", "A", "A", "A", "A", "A", "B", "B",
"B", "B", "B", "B"), v2 = c("A", "B", "C", "A", "B", "C", "A",
"B", "C", "A", "B", "C"), v3 = c("B", "B", "B", "C", "C", "C",
"B", "B", "B", "C", "C", "C"), v4 = c(18.18530, 3.43806,0.00273, 1.42917,
1.05786, 0.00042, 2.37232, 3.01835, 0, 1.13430, 0.92872,
0)), .Names = c("v1", "v2", "v3", "v4"), class = "data.frame", row.names =
c(2L,
9L, 11L, 41L, 48L, 50L, 158L, 165L, 167L, 197L, 204L, 206L))

# this is (an extract of) the OUTPUT file I would like to obtain:
f2 <- structure(list(v1 = c("A", "A", "A", "A", "A", "A", "B", "B",
"B", "B", "B", "B"), v2 = c("A", "B", "C", "A", "B", "C", "A",
"B", "C", "A", "B", "C"), v3 = c("B", "B", "B", "C", "C", "C",
"B", "B", "B", "C", "C", "C"), v4 = c(17.83529, 3.43806,0.00295, 1.77918,
1.05786, 0.0002, 2.37232, 3.01835, 0, 1.13430, 0.92872,
0)), .Names = c("v1", "v2", "v3", "v4"), class = "data.frame", row.names =
c(2L,
9L, 11L, 41L, 48L, 50L, 158L, 165L, 167L, 197L, 204L, 206L))

# please notice that while the aggregated v4 on v3 has changed …
aggregate(f1[,c("v4")],list(f1$v3),sum)
aggregate(f2[,c("v4")],list(f2$v3),sum)

# … the aggregated v4 over v1xv2 has remained unchanged:
aggregate(f1[,c("v4")],list(f1$v1,f1$v2),sum)
aggregate(f2[,c("v4")],list(f2$v1,f2$v2),sum)

Thank you very much in advance for your assitance.

Luca

2015-03-21 13:18 GMT+01:00 Bert Gunter <gunter.berton a gene.com>:

> 1. Still not sure what you mean, but maybe look at ?ave and ?tapply,
> for which ave() is a wrapper.
>
> 2. You still need to heed the rest of Jeff's advice.
>
> 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 Sat, Mar 21, 2015 at 4:53 AM, Luca Meyer <lucam1968 a gmail.com> wrote:
> > Hi Jeff & other R-experts,
> >
> > Thank you for your note. I have tried myself to solve the issue without
> > success.
> >
> > Following your suggestion, I am providing a sample of the dataset I am
> > using below (also downloadble in plain text from
> > https://www.dropbox.com/s/qhmpkkrejjkpbkx/sample_code.txt?dl=0):
> >
> > #this is an extract of the overall dataset (n=1200 cases)
> > f1 <- structure(list(v1 = c("A", "A", "A", "A", "A", "A", "B", "B",
> > "B", "B", "B", "B"), v2 = c("A", "B", "C", "A", "B", "C", "A",
> > "B", "C", "A", "B", "C"), v3 = c("B", "B", "B", "C", "C", "C",
> > "B", "B", "B", "C", "C", "C"), v4 = c(18.1853007621835, 3.43806581506388,
> > 0.002733567617055, 1.42917483425029, 1.05786640463504,
> > 0.000420548864162308,
> > 2.37232740842861, 3.01835841813241, 0, 1.13430282139936,
> 0.928725667117666,
> > 0)), .Names = c("v1", "v2", "v3", "v4"), class = "data.frame", row.names
> =
> > c(2L,
> > 9L, 11L, 41L, 48L, 50L, 158L, 165L, 167L, 197L, 204L, 206L))
> >
> > I need to find a automated procedure that allows me to adjust v3
> marginals
> > while maintaining v1xv2 marginals unchanged.
> >
> > That is: modify the v4 values you can find by running:
> >
> > aggregate(f1[,c("v4")],list(f1$v3),sum)
> >
> > while maintaining costant the values you can find by running:
> >
> > aggregate(f1[,c("v4")],list(f1$v1,f1$v2),sum)
> >
> > Now does it make sense?
> >
> > Please notice I have tried to build some syntax that tries to modify
> values
> > within each v1xv2 combination by computing sum of v4, row percentage in
> > terms of v4, and there is where my effort is blocked. Not really sure
> how I
> > should proceed. Any suggestion?
> >
> > Thanks,
> >
> > Luca
> >
> >
> > 2015-03-19 2:38 GMT+01:00 Jeff Newmiller <jdnewmil a dcn.davis.ca.us>:
> >
> >> I don't understand your description. The standard practice on this list
> is
> >> to provide a reproducible R example [1] of the kind of data you are
> working
> >> with (and any code you have tried) to go along with your description. In
> >> this case, that would be two dputs of your input data frames and a dput
> of
> >> an output data frame (generated by hand from your input data frame).
> >> (Probably best to not use the full number of input values just to keep
> the
> >> size down.) We could then make an attempt to generate code that goes
> from
> >> input to output.
> >>
> >> Of course, if you post that hard work using HTML then it will get
> >> corrupted (much like the text below from your earlier emails) and we
> won't
> >> be able to use it. Please learn to post from your email software using
> >> plain text when corresponding with this mailing list.
> >>
> >> [1]
> >>
> http://stackoverflow.com/questions/5963269/how-to-make-a-great-r-reproducible-example
> >>
> ---------------------------------------------------------------------------
> >> Jeff Newmiller                        The     .....       .....  Go
> Live...
> >> DCN:<jdnewmil a 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 March 18, 2015 9:05:37 AM PDT, Luca Meyer <lucam1968 a gmail.com>
> wrote:
> >> >Thanks for you input Michael,
> >> >
> >> >The continuous variable I have measures quantities (down to the 3rd
> >> >decimal level) so unfortunately are not frequencies.
> >> >
> >> >Any more specific suggestions on how that could be tackled?
> >> >
> >> >Thanks & kind regards,
> >> >
> >> >Luca
> >> >
> >> >
> >> >===
> >> >
> >> >Michael Friendly wrote:
> >> >I'm not sure I understand completely what you want to do, but
> >> >if the data were frequencies, it sounds like task for fitting a
> >> >loglinear model with the model formula
> >> >
> >> >~ V1*V2 + V3
> >> >
> >> >On 3/18/2015 2:17 AM, Luca Meyer wrote:
> >> >>* Hello,
> >> >*>>* I am facing a quite challenging task (at least to me) and I was
> >> >wondering
> >> >*>* if someone could advise how R could assist me to speed the task up.
> >> >*>>* I am dealing with a dataset with 3 discrete variables and one
> >> >continuous
> >> >*>* variable. The discrete variables are:
> >> >*>>* V1: 8 modalities
> >> >*>* V2: 13 modalities
> >> >*>* V3: 13 modalities
> >> >*>>* The continuous variable V4 is a decimal number always greater than
> >> >zero in
> >> >*>* the marginals of each of the 3 variables but it is sometimes equal
> >> >to zero
> >> >*>* (and sometimes negative) in the joint tables.
> >> >*>>* I have got 2 files:
> >> >*>>* => one with distribution of all possible combinations of V1xV2
> >> >(some of
> >> >*>* which are zero or neagtive) and
> >> >*>* => one with the marginal distribution of V3.
> >> >*>>* I am trying to build the long and narrow dataset V1xV2xV3 in such
> >> >a way
> >> >*>* that each V1xV2 cell does not get modified and V3 fits as closely
> >> >as
> >> >*>* possible to its marginal distribution. Does it make sense?
> >> >*>>* To be even more specific, my 2 input files look like the
> >> >following.
> >> >*>>* FILE 1
> >> >*>* V1,V2,V4
> >> >*>* A, A, 24.251
> >> >*>* A, B, 1.065
> >> >*>* (...)
> >> >*>* B, C, 0.294
> >> >*>* B, D, 2.731
> >> >*>* (...)
> >> >*>* H, L, 0.345
> >> >*>* H, M, 0.000
> >> >*>>* FILE 2
> >> >*>* V3, V4
> >> >*>* A, 1.575
> >> >*>* B, 4.294
> >> >*>* C, 10.044
> >> >*>* (...)
> >> >*>* L, 5.123
> >> >*>* M, 3.334
> >> >*>>* What I need to achieve is a file such as the following
> >> >*>>* FILE 3
> >> >*>* V1, V2, V3, V4
> >> >*>* A, A, A, ???
> >> >*>* A, A, B, ???
> >> >*>* (...)
> >> >*>* D, D, E, ???
> >> >*>* D, D, F, ???
> >> >*>* (...)
> >> >*>* H, M, L, ???
> >> >*>* H, M, M, ???
> >> >*>>* Please notice that FILE 3 need to be such that if I aggregate on
> >> >V1+V2 I
> >> >*>* recover exactly FILE 1 and that if I aggregate on V3 I can recover
> >> >a file
> >> >*>* as close as possible to FILE 3 (ideally the same file).
> >> >*>>* Can anyone suggest how I could do that with R?
> >> >*>>* Thank you very much indeed for any assistance you are able to
> >> >provide.
> >> >*>>* Kind regards,
> >> >*>>* Luca*
> >> >
> >> >       [[alternative HTML version deleted]]
> >> >
> >> >______________________________________________
> >> >R-help a 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 a 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.
>

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