Usage
testRetestCES(dat = NULL, moments = NULL, testDat = NULL, retestDat = NULL, parallelTests = 'means', sortItems = FALSE, convertToNumeric = TRUE, digits=4)
parallelSubscales(dat, convertToNumeric = TRUE)
Arguments
dat
A dataframe. For testRetestCES, this dataframe must contain the items in
the scale at both measurement moments. If no dataframe is specified, a
dialogue will be launched to allow the user
to select an SPSS datafile. If only one dataframe is specified, either
the items have to be ordered chronologically (i.e. first all items for the
first measurement, then all items for the second measurement), or the
vector 'moments' has to be used to indicate, for each item, to which
measurement moment it belongs. The number of columns in this dataframe
MUST be even! Note that instead of providing this dataframe, the items
of each measurement moment can be provided separately in testDat and
retestDat as well.
moments
Used to indicate to which measurement moment each item in 'dat' belongs;
should be a vector with the same length as dat has columns, and with two
possible values (e.g. 1 and 2).
testDat, retestDat
Dataframes with the items for each measurement moment: note that the
items have to be in the same order (unless sortItems is TRUE).
parallelTests
A vector indicating which items belong to which parallel test; like the
moments vector, this should have two possible values (e.g. 1 and 2).
Alternatively, it can be character value with 'means' or 'variances';
in this case, parallelSubscales will be used to create roughly
parallel halves.
sortItems
If true, the columns (items) in each dataframe are ordered
alphabetically before starting. This can be convenient to ensure that
the order of the items at each measurement moment is the same.
convertToNumeric
When TRUE, the function will attempt to convert all vectors in the dataframes
to numeric.
digits
Number of digits to print.