This chapter focuses on group dynamics. We review group dynamics in five domains and examine group dynamics within the context of group development. There are many theories about the development of group dynamics, but fundamental to all of them is the notion of groups as social systems. A system is composed of elements in interaction. When group members interact with each other, they form a soc...

Identifying factors that affect human decision making and quantifying their influence remain essential and challenging tasks for the design and implementation of social and technological communication systems. We report results of a behavioral experiment involving decision making in the face of an impending natural disaster. In a controlled laboratory setting, we characterize individual and gro...

Group formation is a quite ubiquitous phenomenon across different animal species, whose individuals cluster together forming communities of diverse size. Previous investigations suggest that, in general, this phenomenon might have similar underlying reasons across the interested species, despite genetic and behavioral differences. For instance improving the individual safety (e.g. from predator...

The rich set of interactions between individuals in the society results in complex community structure, capturing highly connected circles of friends, families, or professional cliques in a social network. Due to the frequent changes in the activity and communication patterns of individuals, the associated social and communication network is subject to constant evolution. The cohesive groups of...

Imitation-matching the configural body movements of another individual-plays a crucial part in social interaction. We investigated whether automatic imitation is not only influenced by who we imitate (ingroup vs. outgroup member) but also by the nature of an expected interaction situation (competitive vs. cooperative). In line with assumptions from Social Identity Theory), we predicted that bot...

We present a coarse convexity result for the dynamics of free group automorphisms: Given an automorphism φ of a finitely generated free group F , we show that for all x ∈ F and 0 ≤ i ≤ N , the length of φ(x) is bounded above by a constant multiple of the sum of the lengths of x and φ (x), with the constant depending only on φ.