reshape time series into panel in r

Question

Now I have time series GDP data for 3 countries. I would like to create a panel for dataset, for further panel analysis. I don't understand how to create it whith reshape package a plm.

           AT      CZ       DE
 1995    68410.7 30457.3 630631.5
 1995.25 68353.5 30213.1 625515.3
 1995.5  68103.3 29766.4 623124.0
 1995.75 67896.0 29661.8 621122.0
 1996    67888.8 29595.8 616673.1
 1996.25 67874.5 29880.0 616645.4

I've found that I can reshape data in such way:

long <- reshape(as.data.frame(GDP.series),varying = list(names(GDP.series)), v.names="GDP",
            timevar = "Country", idvar = "time", ids = row.names(GDP.series),
            times = names(GDP.series),   new.row.names = 1:((dim(GDP.series)[2])*(dim(GDP.series)[1])),direction = "long")

And after that data are in looks like:

    Country     GDP
 1      AT 49149.0
 2      AT 49555.5
 3      AT 49475.9
 4      AT 49507.6
 5      AT 49888.9
 6      AT 50324.5

But the problem with this transformation is that the infromation about time periods is lost. I'm quite beginner, and not everything in code behind is understable for me, especially this part:

  "new.row.names = 1:((dim(GDP.series)[2])*(dim(GDP.series)[1])),direction = "long""

So know my question is how to improve/change code in case data have following format:

       Country     GDP
2013       AT 49149.0
2012.75    AT 49555.5
2012.5     AT 49475.9
2012.25    AT 49507.6
2011       AT 49888.9
2011.75    AT 50324.5

Or if I need to use some other function? Thank you in advance. (Code is taken from this topic: Data Transformation in R for Panel Regression)

Hey welcome to SO!! Could you try from your end and share the intermediate results. We would like to help you on that! but please don't expect to do all from scratch! — joel.wilson, Nov 05 '16 at 14:39
panel of dataset? could you elaborate? share how you want the output to be like? — joel.wilson, Nov 07 '16 at 17:30

score 0 · Accepted Answer · answered Nov 09 '16 at 03:55

This shall answer yours! however remember that rownames of a dataframe must be unique and so you cannot have that. check my output:

data = data.frame(AT = 1:6,CZ = 11:16,DE = 21:26)
rownames(data) = c(2013,2012.75, 2012.5  ,2012.25  ,2011,2011.75)
data$row = rownames(data)

library(reshape2)
data1 = melt(data, id.vars = "row", measure.vars = c("AT","CZ","DE"),
     value.name = "GDP", variable.name = "Country")
data1
       row Country GDP
1     2013      AT   1
2  2012.75      AT   2
3   2012.5      AT   3
4  2012.25      AT   4
5     2011      AT   5
6  2011.75      AT   6
7     2013      CZ  11
8  2012.75      CZ  12
9   2012.5      CZ  13
10 2012.25      CZ  14
11    2011      CZ  15
12 2011.75      CZ  16
13    2013      DE  21
14 2012.75      DE  22
15  2012.5      DE  23
16 2012.25      DE  24
17    2011      DE  25
18 2011.75      DE  26

And if what you sought is a list of dataframes each for a Country then use dlply() :

library(plyr)
dlply(data1, .(Country), function(x) {rownames(x) = x$row;x$row = NULL;x})

$AT
        Country GDP
2013         AT   1
2012.75      AT   2
2012.5       AT   3
2012.25      AT   4
2011         AT   5
2011.75      AT   6

$CZ
        Country GDP
2013         CZ  11
2012.75      CZ  12
2012.5       CZ  13
2012.25      CZ  14
2011         CZ  15
2011.75      CZ  16

$DE
        Country GDP
2013         DE  21
2012.75      DE  22
2012.5       DE  23
2012.25      DE  24
2011         DE  25
2011.75      DE  26

reshape time series into panel in r

1 Answers1