pdata.frame {plm} | R Documentation |
An object of this class is a data.frame with an attribute that describes its time and individual dimensions.
pdata.frame(x, index = NULL, drop.index = FALSE, row.names = TRUE) ## S3 method for class 'pdata.frame': x[i, j, drop = TRUE] ## S3 method for class 'pdata.frame': x[[y]] ## S3 method for class 'pdata.frame': x$y ## S3 method for class 'pdata.frame': print(x, ...) ## S3 method for class 'pdata.frame': as.data.frame(x, row.names = NULL, optional = FALSE, ...)
x |
a data.frame for the pdata.frame function and a
pdata.frame for the methods, |
i |
see Extract , |
j |
see Extract , |
y |
one of the columns of the data.frame , |
index |
this argument indicates the individual and time indexes. See details, |
drop |
see Extract , |
drop.index |
should the indexes be removed from the data.frame ? |
optional |
see as.data.frame |
row.names |
should ``fancy'' row names be computed ? |
... |
further arguments |
The index
argument indicates the dimensions of the panel. It can be:
The index
attribute is a data.frame
which contains the individual and the time indexes. The "[["
and "$"
extract a series from the pdata.frame
. The "index"
attribute is then added to the series and a class attribute "pseries"
is added. The "["
method behaves as for data.frame
, except that the extraction is also applied to the index
attribute. as.data.frame
removes the index from the pdata.frame
and adds it to every series.
a pdata.frame
object: this is a data.frame
with an index
attribute which is a data.frame
with two
variables, the individual and the time indexes.
Yves Croissant
data("Wages", package = "plm") Wag <- pdata.frame(Wages, 595) # Gasoline contains two variables which are individual and time indexes data("Gasoline", package = "plm") Gas <- pdata.frame(Gasoline, c("country","year"), drop = TRUE) # Hedonic is an unbalanced panel, townid is the individual index data("Hedonic", package="plm") Hed <- pdata.frame(Hedonic, "townid", row.names = FALSE)