PRACTICE TEST 4 Why does the speaker discuss a study from 2019?

[00:00.00]Listen to a talk in a psychology class.
[00:01.00]Professor: The bystander effect is a social psychological theory according to which individuals are less likely to offer help to a victim when other people are present. The theory was first proposed by researchers in the 1960s, based on observations. The bystander effect can be explained through two primary factors: diffusion of responsibility and social influence. Diffusion of responsibility occurs when people believe that Someone else will take action, and so they feel less personal responsibility. Social influence involves looking to others for cues on how to behave, especially in ambiguous situations. If others are not helping, individuals may interpret the situation as non-emergency and refrain from intervening.
[00:02.00]More recent studies, however, have disputed the claim that the presence of more bystanders can decrease the likelihood of assistance. One study from 2019 that analyzed video footage from multiple cities found that in 9 out of 10 incidents, at least one bystander did take action to help. This study found that a bystander was actually more likely to intervene when more bystanders were present. Some factors that may influence bystander behavior include the level of danger and whether bystanders know each other.