seqtransn: Number of transitions in a sequence

In TraMineR: Trajectory Miner: a Sequence Analysis Toolkit

Number of transitions in a sequence

Description

Computes the number of transitions (state changes) in each sequence of a sequence object.

Usage

seqtransn(seqdata, with.missing=FALSE, norm=FALSE, pweight=FALSE)

Arguments

seqdata	a state sequence object as defined by the seqdef function.
with.missing	logical: should non-void missing values be treated as a regular state? If FALSE (default) missing values are ignored.
norm	logical. If set as TRUE, the number of transitions is divided by its theoretical maximum, length of the sequence minus 1. When the length of the sequence is 1, the normalized value is set as 0.
pweight	logical. EXPERIMENTAL! If set as TRUE, return count of transitions weighted by their probability to not occur to give higher weights to rare transitions.

Details

A transition in a sequence is a state change between time/position t and t+1. For example, the sequence "A-A-A-A-B-B-A-D-D-D" contains 3 transitions. The maximum number of transitions a sequence can contain is \ell-1 where \ell is the length of the sequence. The number of transitions is obtained by subtracting 1 to the length of the sequence of distinct successive states (DSS).

Value

a one column matrix with the number of transitions in each sequence.

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

seqdss.

Examples

## Creating a sequence object from columns 13 to 24
## in the 'actcal' example data set
data(actcal)
actcal.seq <- seqdef(actcal,13:24)

## Computing the number of transitions
actcal.trans <- seqtransn(actcal.seq)

## Displaying number of transitions in the first 10 sequences
actcal.trans[1:10]

## Example with with.missing argument
data(ex1)
ex1.seq <- seqdef(ex1, 1:13)

seqtransn(ex1.seq)
seqtransn(ex1.seq, with.missing=TRUE)

TraMineR documentation built on Dec. 8, 2024, 3:01 p.m.