Some studies specifically address "durability bias," the tendency to overestimate the length of time future emotional responses will last. Even if people accurately estimate the intensity of their future emotions, they may not be able to estimate the duration of them. Durability bias is generally stronger in reaction to negative events. This is important because people tend to work toward events they believe will cause lasting happiness, and according to durability bias, people might be working toward the wrong things. Similar to impact bias, durability bias causes a person to overemphasize where the root cause of their happiness lies.