Decision Support for Forest Management

In this chapter, decision, decision support, decision-making and planning are defined. We describe what planning means, why planning is needed and what are the aims of planning as a process. We describe the phases decision situations typically involve. We describe the different views for studying decision-making, i.e. the descriptive view, which studies decisions as people make them, and normative view, which studies the ways that may help in making better decisions. We present the different dimensions of decision situations (under certainty/under uncertainty, single goal/multiple goals, discrete/continuous, single decision-maker/multiple decision-makers or stakeholders). Finally, we briefly present classes of methods potentially useful for decision support for these situations such as mathematical optimisation, heuristics, multi-criteria decision-making and group decision-making. 1.1  Decision means choosing from at least two distinct alternatives. Most decisions we face every day may be easy, like picking a meal from a restaurant menu. In most of the decisions, we need to consider several viewpoints (criteria). For instance, in the decision about the meal, it can be considered from the points of view of price, taste, energy content and healthiness. Usually in simple decisions, we balance the different criteria without giving it a conscious thought. Everyday decision-making is a mix of careful judgement and intuitive selection, in other words the slow and fast processes of reasoning (Kahneman 2011). Sometimes the problems that people face in their lives (both professional and private) are so complex or otherwise hard to tackle, however, that some kind of decision support is needed. Decision support means that we formally model the decision. It means that we explicitly account for the multiple criteria in important decisions and systematically explore the effects of different choices on these criteria. It means that the subjective values of decision-makers are made explicit and the evaluation of the possible choices is made transparent (Belton and Stewart 2002). Decision-making, on the other hand, can be defined to include the whole decision process from problem identification to choosing the best alternative © Springer International Publishing Switzerland 2015 A. Kangas et al., Decision Support for Forest Management, Managing Forest Ecosystems 30, DOI 10.1007/978-3-319-23522-6_1 3 (e.g. Kangas 1992). The decision process starts from the discovery of a decision problem, meaning the decision-maker (DM) either realises that he/she has alternative options available and needs to choose the best or realises that the current situation is not satisfactory and some action needs to be taken. In the first case, the DM needs to think of the values based on which to make the choice, and in the latter, the DM needs to define suitable actions based on his/her values. The actual choice is just the last phase of the decision process. Planning, on the other hand, can be defined as the process of thinking about and organising the activities required in order to achieve a desired goal. Planning involves the creation and maintenance of a plan. Thus, planning is very closely related to the decision process, and the plan can be seen as the guide to the final decision. The choice of the best action is not the only decision type. Also ranking or sorting type of problems can be seen as decision problems (Ishizaka and Nemery 2013). The sorting problem can be, for instance, such that the alternative options are sorted to groups of “acceptable” and “not acceptable”, for instance, when selecting a candidate to vote for parliament or choosing research projects to be funded. The ranking problem means that the candidates are ranked from best to worst, for instance, when selecting the best candidate for a post in an organisation. Another type of a decision problem is a design problem (Keeney 1992). It means that a creative new alternative option is sought for. In economic theory, it is usually assumed that people act rationally. A rational decision-maker chooses an alternative which in his/her opinion maximises the utility (Etzioni 1986, von Winterfeldt and Edwards 1986). For this, one has to have a perfect knowledge of the consequences of different decision alternatives, the goals and objectives of the decision-maker and the preferences of the decisionmaker among them. There is evidence that people are not necessarily rational (e.g. Simon 1957, Kahneman 2011). Or, even if they would want to make the best choice, they do not necessarily have enough information for being able to behave fully rationally. Therefore, decision-making can be considered from at least two points of view: one can analyse how the decisions should be made in order to obtain best results (prescriptive approach) or one can analyse how people actually do decisions without help (descriptive approach) (e.g. von Winterfeldt and Edwards 1986). The first approach is normative; it aims at designing and promoting methods that can be used to aid people in their decisions. The second approach represents behavioural research, usually based on experiments on how people actually make decisions under different conditions. In the behavioural studies, people have been found to have many different biases (see, e.g., Kahneman et al. 1991). For instance, people tend to remember the results of their past decisions as better than they actually are or to pay attention only to the information that confirms their pre-assumptions, to name but a few. People have also been found to behave more business-like and unethically in decisions when they have been prompted with money just before the decision (e.g. Kouchaki et al. 2013).