Metrics for describing dyadic movement: a review.

Area of Science:

• Movement ecology
• Collective behaviour analysis

Background:

• Existing studies on collective behaviour in movement ecology often rely on data-driven approaches with simplistic assumptions.
• Current metrics for assessing joint movement may not accurately measure intended aspects of behaviour.

Purpose of the Study:

• To critically evaluate twelve existing metrics for assessing pairwise joint-movement behaviour.
• To analyze the theoretical properties and practical utility of these metrics.
• To determine metric suitability for assessing proximity and coordination in movement.

Main Methods:

• Theoretical analysis of twelve joint-movement metrics.
• Evaluation of metrics against contrasting case scenarios.
• Assessment of metrics based on practical use and parameter dependence.

Main Results:

• Some metrics can be mathematically expressed in general forms.
• Metrics differ in their ability to assess proximity (spatial-temporal closeness) and coordination (synchrony in direction/speed).
• Specific metrics are better suited for proximity, while others are more sensitive to coordination.

Conclusions:

• A graphical representation is provided to aid researchers in selecting appropriate metrics based on proximity and coordination focus.
• The study clarifies the strengths and weaknesses of different joint-movement metrics.
• Guidance is offered for choosing metrics in diverse movement studies.