Compare methods

	Cyberball Paradigm	Bystander Intervention Paradigm
Field	Social Psychology	Social Psychology
Family	Process / pipeline	Process / pipeline
Year of origin	2000	1968
Originator	Kipling Williams and colleagues	Bibb Latane & John Darley
Type	Experimental paradigm for social exclusion	Experimental paradigm for emergency helping
Seminal source	Williams, K. D., Cheung, C. K. T., & Choi, W. (2000). Cyberostracism: Effects of being ignored over the Internet. Journal of Personality and Social Psychology, 79(5), 748-762.	Latane, B., & Darley, J. M. (1968). Group inhibition of bystander intervention in emergencies. Journal of Personality and Social Psychology, 10(3), 215-221.
Aliases	Cyberball, Cyberostracism Paradigm, Virtual Ball-Toss Ostracism Task	Bystander Effect Experiment, Diffusion of Responsibility Paradigm, Emergency Helping Paradigm
Related	3	3
Summary	The Cyberball paradigm, introduced by Williams, Cheung, and Choi in 2000, is the most widely used experimental method for inducing social exclusion in the laboratory. Participants believe they are playing a simple online ball-toss game with two or three other people, who are in fact computer-controlled. In the inclusion condition the participant receives the ball about as often as everyone else; in the exclusion condition the other players throw the ball to each other but, after a few initial throws, stop throwing to the participant entirely, ostracizing them. Despite the triviality and artificiality of the game -- the players are unseen strangers and the ball is virtual -- being excluded reliably threatens four fundamental needs (belonging, self-esteem, control, and meaningful existence) and produces negative mood and a cascade of downstream effects. Cyberball's power, simplicity, and adaptability made it the standard tool for studying the psychology of ostracism and rejection.	The bystander intervention paradigm, pioneered by Latane and Darley in 1968, experimentally demonstrates the bystander effect: the counterintuitive finding that individuals are less likely to help in an emergency when other people are present. In their classic studies a participant encounters a staged emergency -- smoke filling a room, a person apparently having a seizure, or a fall -- either alone or in the company of others (sometimes passive confederates). The dependent measures are whether and how quickly the participant intervenes. Helping reliably declines, and slows, as the number of bystanders increases, an effect Latane and Darley explained through diffusion of responsibility, pluralistic ignorance, and audience inhibition. They formalized the path to helping as a sequence of decisions, each of which the presence of others can derail. The paradigm reshaped understanding of prosocial behavior and emergency response.