R: Extract sequences of distinct successive states

seqdss {TraMineR} | R Documentation

## Extract sequences of distinct successive states

### Description

Extract the sequence of distinct successive states from each sequence in a object.

### Usage

    seqdss(seqdata, with.missing=FALSE)

### Arguments

`seqdata` | a sequence object as defined by the `seqdef` function.
`with.missing` | Should non-void missing values be considered as regular states? See Details.

### Details

Returns a sequence object containing the sequences of distinct successive states (DSS). The spell durations are not taken into account. E.g., the DSS contained in `'D-D-D-D-A-A-A-A-A-A-A-D'` is `'D-A-D'`. Associated durations can be extracted with the `seqdur` function.

When `{with.missing=TRUE}`, non-void missing values are considered as a regular state of the alphabet. For example, the DSS of `A-A-*-*-*-B-B-C-C-D` is `A-*-B-C-D`.

When `with.missing=FALSE` (default) missing values are ignored and a substring `A-A-*-*-*A` for example will be considered as a single spell in `A` while the DSS of this substring would be `A-*-A` whith `with.missing=TRUE`.

See seqdef on options for handling missing values when creating sequence objects.

### Value

a sequence object containing the distinct state sequence (DSS) for each sequence in the object given as argument.

### Author(s)

Alexis Gabadinho and Gilbert Ritschard

### See Also

`seqdur`.

### Examples

    ## Creating a sequence object from columns 13 to 24
    ## in the 'actcal' example data set
    ## Here we retain the first 10 sequences only.
    data(actcal)
    actcal.seq <- seqdef(actcal[1:10,13:24])

    ## Retrieving the DSS
    actcal.dss <- seqdss(actcal.seq)

    ## Displaying the DSS for the first 10 sequences
    actcal.dss

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

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

[Package TraMineR version 2.2-4 Index]