(copy from http://en.wikipedia.org/wiki/Decision_making)

Decision making is the cognitive process leading to the selection of a course of action among alternatives. Every decision making process produces a final choice. It can be an action or an opinion. It begins when we need to do something but we do not know what. Therefore, decision-making is a reasoning process which can be rational or irrational, and can be based on explicit assumptions or tacit assumptions.

決策是一種在眾多選項中作出選擇行動的認知程序。每一個決策程序最終都會「選定」一個結論。這個結論可以是一個實際行動,或是一種看法意見。決策行為的起始點,是當我們需要做某些事情,但是卻不知道從何開始。因此,決策是一個推論程序;並可以理性的,或是非理性的程序;也可能是基於外顯的假定,或是內隱的假定。

Common examples include shopping, deciding what to eat, when to sleep, and deciding whom or what to vote for in an election or referendum.

例如購物、決定吃什麼,何時上床就寢,投票給誰等等。

Decision making is said to be a psychological construct. This means that although we can never "see" a decision, we can infer from observable behaviour that a decision has been made. Therefore, we conclude that a psychological event that we call "decision making" has occurred. It is a construction that imputes commitment to action. That is, based on observable actions, we assume that people have made a commitment to affect the action.

決策被稱為一種心理上的構念[?](construct)。即,即使我們無法真的「看見」決策,我們可以透過可觀察的行為,推導出決策行為的過程,以此,察覺出「決策」的心理事件。也就是說,根據可觀察的行動,我們假定人們做出一項心理決定,進而完成行動。

Structured rational decision making is an important part of all science-based professions, where specialists apply their knowledge in a given area to making informed decisions. For example, medical decision making often involves making a diagnosis and selecting an appropriate treatment. Some research using naturalistic methods shows, however, that in situations with higher time pressure, higher stakes, or increased ambiguities, experts use intuitive decision making rather than structured approaches, following a recognition primed decision approach to fit a set of indicators into the expert's experience and immediately arrive at a satisfactory course of action without weighing alternatives.

有結構的理性決策對所有科學專業都是重要的。

Due to the large number of considerations involved in many decisions, computer-based decision support systems have been developed to assist decision makers in considering the implications of various courses of thinking. They can help reduce the risk of human errors.
The systems which try to realize some human/cognitive decision making functions are called Intelligent Decision Support Systems (IDSS), see for ex. [http://citeseer.ist.psu.edu/701938.html "An Approach to the Intelligent Decision Advisor (IDA) for Emergency Managers, 1999"].

Decision making style

According to behavioralist Isabel Briggs Myers (1962), a person's decision making process depends to a significant degree on their cognitive style. Starting from the work of Carl Jung, Myers developed a set of four bi-polar dimensions, called the Myers-Briggs Type Indicator (MBTI). The terminal points on these dimensions are: thinking and feeling; extroversion and introversion; judgement and perception; and sensing and intuition. She claimed that a person's decision making style is based largely on how they score on these four dimensions. For example, someone that scored near the thinking, extroversion, sensing, and judgement ends of the dimensions would tend to have a logical, analytical, objective, critical, and empirical decision making style.

Cognitive and personal biases in decision making

It is generally agreed that biases can creep into our decision making processes, calling into question the correctness of a decision. It is not generally agreed, however, which normative models are to be used to evaluate what constitutes an erroneous decision. Nor is the scientific evidence for all of the biases agreed upon. So, while it is agreed that decision making can be biased, how to tell when it is, and specific cases of biases, are often challenged. The issue in general can be quite controverial among scholars in the field. Below is a list of some of the more commonly debated cognitive biases.

  • Selective search for evidence - We tend to be willing to gather facts that support certain conclusions but disregard other facts that support different conclusions.
  • Premature termination of search for evidence - We tend to accept the first alternative that looks like it might work.
  • Inertia - Unwillingness to change thought patterns that we have used in the past in the face of new circumstances.
  • Contrariness or rebelliousness - Unwillingness to share a view with a perceived oppressive authority.
  • Experiential limitations - Unwillingness or inability to look beyond the scope of our past experiences; rejection of the unfamiliar.
  • Selective perception - We actively screen-out information that we do not think is salient. (See prejudice.)
  • Wishful thinking or optimism - We tend to want to see things in a positive light and this can distort our perception and thinking.
  • Choice-supportive bias occurs when we distort our memories of chosen and rejected options to make the chosen options seem relatively more attractive.
  • Recency - We tend to place more attention on more recent information and either ignore or forget more distant information. (See semantic priming.)
  • Repetition bias - A willingness to believe what we have been told most often and by the greatest number of different of sources.
  • Anchoring and adjustment - Decisions are unduly influenced by initial information that shapes our view of subsequent information.
  • Group think - Peer pressure to conform to the opinions held by the group.
  • Source credibility bias - We reject something if we have a bias against the person, organization, or group to which the person belongs: We are inclined to accept a statement by someone we like. (See prejudice.)
  • Incremental decision making and escalating commitment - We look at a decision as a small step in a process and this tends to perpetuate a series of similar decisions. This can be contrasted with 'zero-based decision making'. (See slippery slope.)
  • Inconsistency - The unwillingness to apply the same decision criteria in similar situations.
  • Attribution asymmetry - We tend to attribute our success to our abilities and talents, but we attribute our failures to bad luck and external factors. We attribute other's success to good luck, and their failures to their mistakes.
  • Role fulfillment - We conform to the decision making expectations that others have of someone in our position.
  • Underestimating uncertainty and the illusion of control - We tend to underestimate future uncertainty because we tend to believe we have more control over events than we really do. We believe we have control to minimize potential problems in our decisions.
  • Faulty generalizations - In order to simplify an extremely complex world, we tend to group things and people. These simplifying generalizations can bias decision making processes.
  • Ascription of causality - We tend to ascribe causation even when the evidence only suggests correlation. Just because birds fly to the equatorial regions when the trees lose their leaves, does not mean that the birds migrate because the trees lose their leaves.

For an explanation of the logical processes behind some of these biases, see logical fallacy.

Cognitive neuroscience of decision making

The anterior cingulate cortex (ACC) and orbitofrontal cortex are brain regions involved in decision making processes. Studies with patients with orbitofrontal lesions have used the Iowa gambling task to show abnormal patterns of risk taking. A recent neuroimaging study, [http://www.nature.com/cgi-taf/DynaPage.taf?file=/neuro/journal/v7/n11/abs/nn1339.html Interactions between decision making and performance monitoring within prefrontal cortex], found distinctive patterns of neural activation in these regions depending on whether decisions were made on the basis of personal volition or following directions from someone else.

Another recent study by [http://www.nature.com/neuro/journal/v9/n7/abs/nn1724.html Kennerly, et al. (2006)] found that lesions to the ACC in the macaque resulted in impaired decision making in the long run of reinforcement guided tasks suggesting that the ACC is responsible for evaluating past reinforcement information and guiding future action.

Decision making in groups

Decision making in groups is sometimes examined separately as process and outcome. Process refers to the interactions among individuals that lead to the choice of a particular course of action. An outcome is the consequence of that choice. Separating process and outcome is convenient because it helps explain that a good decision making processes does not guarantee a good outcome, and that a good outcome does not presuppose a good process. Thus, for example, managers interested in good decision making are encouraged to put good decision making processes in place. Although these good decision making processes do not guarantee good outcomes, they can tip the balance of chance in favor of good outcomes.

A critical aspect for decision making groups is the ability to converge on a choice.

Politics is one approach to making decisions in groups. This process revolves around the relative power or ability to influence of the individuals in the group. Some relevant ideas include coalitions among participants as well as influence and persuasion. The use of politics is often judged negatively, but it is a useful way to approach problems when preferences among actors are in conflict, when dependencies exist that cannot be avoided, when there are no super-ordinate authorities, and when the technical or scientific merit of the options is ambiguous.

In addition to the different processes involved in making decisions, groups can also have different decision rules. A decision rule is the approach used by a group to mark the choice that is made.

  • Unanimity is commonly used by juries in criminal trials in the United States. Unanimity requires everyone to agree on a given course of action, and thus imposes a high bar for action.
  • Majority requires support from more than 50% of the members of the group. Thus, the bar for action is lower than with unanimity and a group of "losers" is implicit to this rule.
  • Consensus decision-making tries to avoid "winners" and "losers". Consensus requires that a majority approve a given course of action, but that the minority agree to go along with the course of action. In other words, if the minority opposes the course of action, consensus requires that the course of action be modified to remove objectionable features.
  • Gathering involves all participants acknowledging each other's needs and opinions and tends towards a problem solving approach in which as many needs and opinions as possible can be satisfied. It allows for multiple outcomes and does not require agreement from some for others to act.
  • Sub-committee involves assigning responsibility for evaluation of a decision to a sub-set of a larger group, which then comes back to the larger group with recommendations for action. Using a sub-committee is more common in larger governance groups, such as a legislature. Sometimes a sub-committee includes those individuals most affected by a decision, although at other times it is useful for the larger group to have a sub-committee that involves more neutral participants.

Less desirable group decision rules are:

  • Plurality, where the largest block in a group decides, even if it falls short of a majority.
  • Dictatorship, where one individual determines the course of action.
    : see also: groupthink

Plurality and dictatorship are less desirable as decision rules because they do not require the involvement of the broader group to determine a choice. Thus, they do not engender commitment to the course of action chosen. An absence of commitment from individuals in the group can be problematic during the implementation phase of a decision.

There are no perfect decision making rules. Depending on how the rules are implemented in practice and the situation, all of these can lead to situations where either no decision is made, or to situations where decisions made are inconsistent with one another over time.

Principles

The ethical principles of decision making vary considerably. Some common choices of principles and the methods which seem to match them include:

There are many grades of decision making which have an element of participation. A common example is that of institutions making decisions which affect those they are charged to provide for. In such cases an understanding of what participation is, is crucial to understand the process and the power structures at play.

Decision making in one's personal life

Some of the decision making techniques that we use in everyday life include:

  • listing the advantages and disadvantages of each option, popularized by Benjamin Franklin
  • flipping a coin, cutting a deck of playing cards, and other random or coincidence methods
  • accepting the first option that seems like it might achieve the desired result
  • tarot cards, astrology, augurs, revelation, or other forms of divination
  • acquiesce to a person in authority or an "expert"

An alternative may be to apply one of the processes described below, in particular in the Business and Management section.

Decision making in healthcare

In the health care field, the steps of making a decision may be remembered with the mnemonic 'BRAND', which includes

  • Benefits of the action
  • Risks in the action
  • Alternatives to the prospective action
  • Nothing: that is, doing nothing at all
  • Decision

Path dependency

Main article: path dependency

It is perhaps pertinent to note that the cost of making no decision at all itself is a factor, and that the benefit of making some decision, even a random choice, can be beneficial in the longer term. Thus the reversibility of an action may be a good way to judge whether or not an action or process is beneficial. A resource can also be viewed as something expendable, or bearing a cost, rather than the implication of selecting something irrevocably.

Even life and death decisions have been priced this way, as in the insurance industry.

Decision making in business and management

In general, business and management systems should be set up to allow decision making at the lowest possible level.

Several decision making models for business include:

Decision-makers and influencers

In the context of industrial goods marketing, there is much theory, and even more opinion, expressed about how the various `decision-makers' and `influencers' (those who can only influence, not decide, the final decision) interact. Decisions are frequently taken by groups, rather than individuals, and the official buyer often does not have authority to take the decision.

Miller & Heiman, for example, offered a more complex view of industrial buying decisions (particularly in the area of `complex sales' of capital equipment). They see three levels of decision-making:

'economic buying influence' - the decision-maker who can authorize the necessary funds for purchase

'user buying influences' - the people in the buying company who will use the product and will specify what they want to purchase

'technical buying influence' - the `experts' (including, typically, the buying department) who can veto the purchase on technical grounds

Webster and Wind, in a similar vein, identify six roles within the `buying centre':

'users' - who will actually use the product or service

'influencers' - particularly technical personnel

'deciders' - the actual decision-makers

'approvers' - who formally authorize the decision

'buyers' - the department with formal authority

'gatekeepers' - those who have the power to stop the sellers reaching other members of the `buying centre'

References

[http://futureobservatory.dyndns.org/9432.htm] R. B. Miller and S. E. Heiman, 'Strategic Selling ' (Kogan Page, 1989)
F. E. Webster and Y. Wind, 'Organizational Buying Behavior ' (Prentice-Hall, 1972)
D. Mercer, ‘Marketing’ (Blackwell, 1996)

See also

Some important research journals