Calgary discovers the Bystander Effect

Why didn’t more people come to the aid of Calgary victim Wong Shuk Yee? asked Metro News. This is basically an instance of the Bystander Effect which has been observed for quite some time by psychologists:

The bystander effect or Genovese syndrome is a social psychological phenomenon that refers to cases where individuals do not offer any means of help in an emergency situation to the victim when other people are present. The probability of help has often appeared to be inversely related to the number of bystanders; in other words, the greater the number of bystanders, the less likely it is that any one of them will help. The mere presence of other bystanders greatly decreases intervention. In general, this is believed to happen because as the number of bystanders increases, any given bystander is less likely to notice the situation, interpret the incident as a problem, and less likely to assume responsibility for taking action.