1. There are four stages to deciding to help someone in trouble. 1. Notices the incident. 2. Interprets incident as an emergency. 3. Assumes responsibility. 4. Attempts to help.
2. The problem, happens during stage 3. When there are larger groups of people, the responsibility is "shared" namely, individuals are less likely to offer help.
3. Situational ambiguity
   1. In ambiguous situations, (i.e., it is unclear that there is an emergency) people are much less l ikely to offer assistance than in situations involving a clear-cut emergency
4. Perceived cost
   1. The likelihood of helping increases as the perceived cost to our­selves declines
5. Diffusion of responsibility
   1. The presence of others may diffuse the sense of individual responsibility.
6. Similarity
   1. People are more willing to help others whom they perceive to be similar to themselves—people who share a common background and beliefs.
7. Mood
   1. People are generally more willing to help others when they are in a good mood
8. Gender
   1. Despite changes in traditional gender roles, women in need are more likely than men in need to receive assistance from strangers
9. Attributions of the cause of need
   1. People are much more likely to help others they judge to be innocent victims than those they believe have brought their problems on themselves
10. Social norms
    1. Social norms prescribe behaviors that are expected of people in social situations