It's easy to think that the bystander effect isn't applicable to modern lives today. As humans, we have a tendency to be overly optimistic in the assessment of our hypothetical action. When we read about the Kitty Genovese's situation, we're quick to distance ourselves from those actions, saying outraged things like "Oh, I would NEVER do something like that."
In actuality, however, those are not isolated incidents as the bystander effect manifests itself in real world situations. To give a quick definition, the bystander effect is the phenomenon that occurs when people do not offer help in emergency situations because other people are present. Oftentimes, people in those situations are less likely to assume responsibility by believing that others will "take care" of the situation. However, when no one assumes responsibility, in the end, no help is offered.
Recently, a tragic incident demonstrating the bystander effect triggered international outrage. In the Guangdong province of China, a two-year-old girl--Wang Yue--was crushed by a truck driver and later died of her injuries. The true tragedy was that as Wang Yue lay dying in the street, 18 passerbys skirted around her body without offering any form of emergency aid. In fact, it was after another truck ran Wang Yue over again that a female scavenger eventually helped her by calling emergency services. The entire incident was captured via security cameras and incited a hailstorm of condemnation.
I'll refrain from posting the video here as it is graphic, but the incident demonstrates the tragic aftermath of the bystander effect in the modern world. Furthermore, it horrifically establishes that the bystander effect can occur in everyday situations when we're least expecting it, and with devastating effects. As psychology students, the only way we can truly prevent terrible incidents like this from happening is to be aware of the effects of situations on our behaviors. By becoming aware, we gain the ability to fight these behaviors to make sure another Kitty Genovese or Wang Yue isn't made a victim.