seqtab {TraMineR}

Frequency table of the sequences

Description

Computes the frequency table of the sequences (count and percent of each sequence).

Usage

seqtab(seqdata, idxs = 1:10, weighted = TRUE, format = "SPS", tlim)

Arguments

seqdata

a sequence object as defined by the seqdef function.

idxs

returns the table for the sequences at ranks 'idxs' in the list of distinct sequences sorted in decreasing order of their frequencies. Default is 1:10, i.e. the 10 most frequent sequences. Can be any subset, like 5:10 (fifth to tenth most frequent sequences) or c(2,10) (second and tenth most frequent sequences). Set idxs=0 to get the table for the whole set of distinct sequences.

weighted

if TRUE (default), frequencies account for the weights, if any, assigned to the state sequence object (see seqdef). Set to FALSE for ignoring weights.

format

format used for displaying the rownames (the sequences) in the output table. Default is SPS format, which yields shorter and more readable sequence representations. Alternatively, "STS" may be specified.

tlim

Deprecated. Use idxs instead.

Details

The weighted argument has no effect when no weights were assigned to the state sequence object since weights default in that case to 1.

Value

An object of class stslist.freq. This is actually a state sequence object (containing a list of state sequences) with added attributes, among others the freq attribute containing the frequency table. There are print and plot methods for such objects. More sophisticated plots can be produced with the seqplot function.

Author(s)

Alexis Gabadinho (with Gilbert Ritschard for the help page)

References

Gabadinho, A., G. Ritschard, N. S. Müller and M. Studer (2011). Analyzing and Visualizing State Sequences in R with TraMineR. Journal of Statistical Software 40(4), 1-37.

See Also

seqplot, plot.stslist.freq.

Examples

## Creating a sequence object from the actcal data set
data(actcal)
actcal.lab <- c("> 37 hours", "19-36 hours", "1-18 hours", "no work")
actcal.seq <- seqdef(actcal, 13:24, labels=actcal.lab)

## 10 most frequent sequences in the data
seqtab(actcal.seq)

## With idxs=0, we get all distinct sequences in the data set
## sorted in decreasing order of their frequency
stab <- seqtab(actcal.seq, idxs=0)
head(stab)
tail(stab)

## Example with weights
## from biofam data set using weigths
data(ex1)
ex1.seq <-  seqdef(ex1, 1:13, weights=ex1$weights)

## Unweighted frequencies
seqtab(ex1.seq, weighted=FALSE)

## Weighted frequencies
seqtab(ex1.seq, weighted=TRUE)