In Sources of Power: How People Make Decisions, Klein identifies two basic ways people make decisions: singular evaluation and comparative evaluation (see Table 8-1). In singular evaluation, the first option is considered and checked against some kind of criteria (do I want to wear this green shirt today?). If it meets the criteria, it's chosen and the decision maker moves on to more important things. If it doesn't meet the criteria, another idea or choice is considered, and the process repeats (how about this yellow shirt?). A good example of this might be finding a place to go to the bathroom when you really have to go, or trying to find something to eat when you're ravenously hungry. The first available restroom or restaurant you find is sufficient, and there's no need to explore for alternatives.
|Decision approach||How it works||Example|
|Singular evaluation||The first reasonable alternative found is accepted.||You seriously need to go to the bathroom.|
|Comparative evaluation||Several alternatives are evaluated against each other before deciding.||You're deciding on which tropical island to purchase..|
At the other end of the decision-making spectrum, comparative evaluation requires seeking alternatives before deciding. Considering what city to move your family to is a good example of a common comparative evaluation decision.
Singular evaluation makes sense for situations where the difference between a great ...