Table 1 Definitions and interpretations in the context of activity data, for various recurrence plot quantifiers that are used in this work.

DET

Ratio of diagonal structures to total recurrence points.

Level of deterministic activity in the data.

Lower levels indicate more randomness

LAM

Ratio of vertical structures to total recurrence points.

Level of slowly evolving processes in the time series.

Higher levels indicate more activities that linger

\(L_{avg}\)

Mean length of diagonal structures

Average duration of recurrent physical activity

Higher levels indicate longer recurrent physical activities

\(L_{ent}\)

Entropy of diagonal line distribution

Diversity of durations of recurrent physical activity patterns

Higher levels indicate recurrent physical activities of varying durations

\(V_{avg}\)

Mean length of vertical structures

Average duration of static activity patterns

Higher levels indicate lingering physical activities that last longer

\(V_{ent}\)

Entropy of vertical line distribution

Diversity of durations of static activity patterns

Higher levels indicate lingering physical activities of varying durations

\(\frac{LAM}{DET}\)

Ratio of LAM to DET measures

Level of statis as compared to deterministic structure

Changes in this ratio has been shown to be an indicator of change in stability^45,46.