確証バイアス
Optimism and belief that one has control over what will still be positive outcomes lead to continued self-justification of commitment to actions. People add to their initial personal investments in the hope they will overcome currently negative results. This was illustrated in a case study by Staw, where providing business students with manipulated responsibilities for initial decisions and their outcomes resulted in the greatest commitment to increased actions and resources when the initial decision assigned was made directly by the student with poor outcomes. In these instances, people take further risk in an attempt to avoid further problems. This is even more likely when subjects view current issues as having unstable reasoning rather than stable reasoning, or when the individual is unwilling to admit mistakes. They then believe the situation will stabilize or turn around. Confirmation bias can also lead to escalation of commitment as individuals are then less likely to recognize the negative results of their decisions. On the other hand, if the results are recognized, they can be blamed on unforeseeable events occurring during the course of the project.