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Dynamics of Helping Behavior and Networks in a Small World

Hang-Hyun Jo·Woo-Sung Jung·Hie-Tae Moon
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Abstract

To investigate an effect of social interaction on the bystanders' intervention in emergency situations a rescue model was introduced which includes the effects of the victim's acquaintance with bystanders and those among bystanders from a network perspective. This model reproduces the experimental result that the helping rate (success rate in our model) tends to decrease although the number of bystanders $k$ increases. And the interaction among homogeneous bystanders results in the emergence of hubs in a helping network. For more realistic consideration it is assumed that the agents are located on a one-dimensional lattice (ring), then the randomness $p \in [0,1]$ is introduced: the $kp$ random bystanders are randomly chosen from a whole population and the $k-kp$ near bystanders are chosen in the nearest order to the victim. We find that there appears another peak of the network density in the vicinity of $k=9$ and $p=0.3$ due to the cooperative and competitive interaction between the near and random bystanders.

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Hang-Hyun Jo, Woo-Sung Jung, Hie-Tae Moon. 2006-06-10. Dynamics of Helping Behavior and Networks in a Small World. https://doi.org/10.1103/physreve.74.026120

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