| 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 serie from the pdata.frame. The "index"
attribute is then added to the serie 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. The as.data.frame remove the index from
the pdata.frame and add 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)