You have entered the Pathfinder's overview decision tree for appraising adaptation options.

The crucial methodological choice faced at this stage is whether to apply a formal approach, a deliberative / participatory approach (Renn 2008), both of these or whether to leave decision making to our intuition (see decision tree). Formal decision appraisal methods are based on formalizing the decision and then applying mathematical reasoning prescribing which options should be chosen. Examples of such methods are multi-criteria analysis, cost-benefit analysis or robust decision making. In contrast, deliberative approaches appraise options through discursively harmonizing preferences and eliciting information. Intuitive decisionmaking relies on cognitive processes that have been developed through experience and learning.

A first decision node to consider is whether the adaptation situation is individual or collective because collective adaptations are often characterized by the various stakeholders involved having different preferences on outcomes, while for individual adaptation this is, of course, not the case.

If the adaptation situation consists of a private individual actor, the subsequent decision node concerns whether to formalise the decision or to decide intuitively. For individuals, formal decision appraisal methods may be superior to intuitive decision making, as there are many consistently observed biases in individuals’ decision making including overestimating the value of low probability high impact events (Tversky and Kahneman 1973; Weber and Hilton 1990), strong aversion to potential losses (Kahneman and Tversky 1979) and problems discounting future events (Laibson 1997; Karp 2003; Frederick et al. 2002) . On the other hand, research in psychology has shown that informal decision making of individuals may be remarkably effective and in the presence of limited or highly ambiguous information even consistently lead to better results than formal methods (Gigerenzer 2000). This is particularly true in settings where an individual has had extensive experience with similar decisions, and the decision provides immediate feedback and thus an opportunity for learning (Kahne man et al. 1982).