(The Lack of) Optimistic Biases in Response to the 1994 Northridge Earthquake: The Role of Personal Experience

The tendency to believe that one's risk is less than that of one's peers is a well-documented and pervasive tendency. This optimistic bias is reduced in certain circumstances, such as when people have personal experience with an event, although it may reappear with time. University students who experienced the 1994 Northridge, CA earthquake were asked 1 week after the quake about their optimistic biases concerning earthquakes and a variety of other events. Students were followed every 2 weeks over the next 5 months. In addition, two new groups of students were surveyed at 2 and 4 months after the earthquake. As expected, no optimistic bias for earthquakes was present immediately after the earthquake (but other events did show the bias). Contrary to previous research, no bias for earthquakes was present even 5 months after the earthquake. Those who had personal experience with injury or monetary loss as a result of the earthquake showed less optimism about injury in future earthquakes than those with no personal experience of injury or loss. Results are discussed in terms of the moderators of the optimistic bias.