# Empirical study on social groups in pedestrian evacuation dynamics

## TL;DR

This empirical study investigates how social groups within pedestrian crowds affect evacuation dynamics, revealing that group behavior can influence evacuation times and configurations, with larger groups potentially reducing evacuation times due to self-ordering effects.

## Contribution

The paper introduces new parameters to quantify social group dynamics and configurations, providing empirical evidence on their impact during evacuations.

## Key findings

- Large groups may decrease evacuation times due to self-ordering.
- Social groups tend to form elliptical shapes aligned with movement.
- Cooperative behavior increases group aggregation and causes intermittent evacuation patterns.

## Abstract

Pedestrian crowds often include social groups, i.e. pedestrians that walk together because of social relationships. They show characteristic configurations and influence the dynamics of the entire crowd. In order to investigate the impact of social groups on evacuations we performed an empirical study with pupils. Several evacuation runs with groups of different sizes and different interactions were performed. New group parameters are introduced which allow to describe the dynamics of the groups and the configuration of the group members quantitatively. The analysis shows a possible decrease of evacuation times for large groups due to self-ordering effects. Social groups can be approximated as ellipses that orientate along their direction of motion. Furthermore, explicitly cooperative behaviour among group members leads to a stronger aggregation of group members and an intermittent way of evacuation.