[R] merge a list of data frames

[Sam Steingold]

> * David Winsemius <qjvafrzvhf at pbzpnfg.arg> [2012-09-05 21:02:16 -0700]:
>
> On Sep 5, 2012, at 8:51 PM, Sam Steingold wrote:
>
>> I have a list of data frames:
>> 
>>> str(data)
>> List of 4
>> $ :'data.frame':	700773 obs. of  3 variables:
>>  ..$ V1: chr [1:700773] "200130446465779" "200070050127778"
>> "200030633708779" "200010587002779" ...
>>  ..$ V2: int [1:700773] 0 0 0 0 0 0 0 0 0 0 ...
>>  ..$ V3: num [1:700773] 1 1 1 1 1 ...
>> $ :'data.frame':	700773 obs. of  3 variables:
>>  ..$ V1: chr [1:700773] "200130446465779" "200070050127778"
>> "200030633708779" "200010587002779" ...
>>  ..$ V2: int [1:700773] 0 0 0 0 0 0 0 0 0 0 ...
>>  ..$ V3: num [1:700773] 1 1 1 1 1 ...
>> $ :'data.frame':	700773 obs. of  3 variables:
>>  ..$ V1: chr [1:700773] "200130446465779" "200070050127778"
>> "200030633708779" "200010587002779" ...
>>  ..$ V2: int [1:700773] 0 0 0 0 0 0 0 0 0 0 ...
>>  ..$ V3: num [1:700773] 1 1 1 1 1 ...
>> $ :'data.frame':	700773 obs. of  3 variables:
>>  ..$ V1: chr [1:700773] "200160325893778" "200130647544079"
>> "200130446465779" "200120186959078" ...
>>  ..$ V2: int [1:700773] 0 0 0 0 0 0 0 0 0 0 ...
>>  ..$ V3: num [1:700773] 1 1 1 1 1 1 1 1 1 1 ...
>> 
>> I want to merge them.
>
> Why? What are you expecting?

these are the results of applying a model to the test data.
the first column is the ID
the second column is the actual value
the third column is the model score

after I will merge the frames, I will
1. check that all the V2 columns are identical and drop all but one
(I guess I could just merge on c("V1","V2") instead, right?)

2. compute the sum (or the mean, whatever is easier) of all the V3
columns

3. sort by the sum/mean of the V3 columns and evaluate the combined
model using the lift quality metric
(http://dl.acm.org/citation.cfm?id=380995.381018)

I have many more score files (not just 4), so it is not practical for me
to rename the column to something unique.



-- 
Sam Steingold (http://sds.podval.org/) on Ubuntu 12.04 (precise) X 11.0.11103000
http://www.childpsy.net/ http://www.memritv.org http://truepeace.org
http://jihadwatch.org http://mideasttruth.com http://americancensorship.org
To be popular with ladies one has to be smart, handsome & rich. Or to be a cat.