Decision Theory: Introduction SpringerLink

While decision theory has history of applications to real world problems in many disciplines, including economics, risk analysis, business management, and theoretical behavioral ecology, it has more recently gained acknowledgment as a beneficial approach to conservation in the last 20 years (Maguire 1986). There are two categories of decisions theories that include normative or prescriptive decision theory to identify the best decision to take, assuming an ideal decision maker who is fully informed, able to compute with perfect accuracy, and fully rational. The practical application of this prescriptive approach is called decision analysis, and aimed at finding tools, methodologies and software to help people make better decisions. The most systematic and comprehensive software tools developed in this way are called decision support systems.

Thus, we can state that if a team approach had been followed instead of a more individual one, the results would probably have been different. The central belief of the research, is that classic decision theory could benefit from a team approach, which reduces the risk that a decision may lead to undesirable consequences. As demonstrated with the case study, within organizations, the decision-making is not a solitary action. Decisions, in fact, are made within a team and in order to be able to function effectively in a group, and manage group situations, there are essential skills.

Interesting though these alternatives are, none has seriously challenged the normative status of SEU. Though highly idealized, and far from adequate as a description of human behavior, SEU remains the best overall account of rational decision making. Opponents of SEU will, of course, deny that risks should be measured by the costs of insuring against them.

  • Let \(S\) be afinite set of prospects, and \(\preceq\) a weak preference relation on\(S\).
  • Indeed, some of the most compelling counterexamples to EU axioms ofpreference rest on ethical considerations.
  • (For furtherdevelopments of this position, see the entry on epistemic utility arguments for probabilism.)
  • But perhaps we want to know more than canbe inferred from such a utility function—we want to know howmuch \(C\) is preferred over \(B\), compared to how much \(B\) ispreferred over \(A\).
  • It should moreover be evident, given the discussion of the Sure ThingPrinciple (STP) in Section 3.1, that Jeffrey’s theory does not have this axiom.

Appendix 2.2 Desiderata of Normative Decision Theory

  • If she is lucky, she may have access to comprehensive weatherstatistics for the region.
  • Now we will discuss the statistical approach that quantifies the tradeoffs between various decisions using probabilities and costs that accompany such decisions.
  • Expected utility theory has been criticised for not allowing for valueinteractions between outcomes in different, mutually incompatiblestates of the world.
  • Another example is that decision-makers may be biased towards preferring moderate alternatives to extreme ones.

It is used to inform decision-making in both personal and professional contexts, from investment decisions to medical diagnosis and treatment. They generally take some medical observations before making decisions – A reasonable observation is to perform a blood test and But there is very high risk in the doctor’s prescription since the doctor is considering only prior probability – that is how many cases of flu and how many cases of really sick has been encountered.

Appendix 2.5 Results, Outcomes and Decision Quality

The study of decision-making processes, to be understood as the role of human factors, becomes particularly interesting in complex organizations. This research aims to analyze how an effective team, within organizations, can develop a more correct and effective decision-making, in order to get an optimal solution, overcoming the typical uncertainty. The paper describes the point of departure of decision in complex, time-pressured, uncertain, ambiguous and changing environments. The use of a leading case (the Tenerife air accident, 1977), will lead us to the desired results, i.e. to demonstrate how an effective decisional process, including team dynamics, can be useful to reduce the risk, present in all decisions, and reduce errors.

It’s time to build

To accommodate this,they extend the Boolean algebra in Jeffrey’s decision theory tocounterfactual propositions, and show that Jeffrey’sextended theory can represent the value-dependencies one often findsbetween counterfactual and actual outcomes. In particular, theirtheory can capture the intuition that the (un)desirability of winningnothing partly depends on whether or not one was guaranteed to winsomething had one chosen differently. Therefore, their theory canrepresent Allais’ preferences as maximising the value of anextended Jeffrey-desirability function.

The investor can use the historical data to estimate the expected return and risk of the stock and make an informed decision. Bounded Rationality is a theory that suggests that there are limits upon how rational a decision maker can actually be. The constraints placed on decision making are due to high costs, limitations in human abilities, lack of time, limited technology, and finally availability of information. A well-known sequential decision problem is the one facing Ulysses onhis journey home to Ithaca in Homer’s great tale from antiquity.Ulysses must make a choice about the manner in which he will sail pastan island inhabited by sweet-singing sirens. Some have suggested that when the precautionary principle isinterpreted as a decision-rule, the feature that most clearlydistinguishes it from the EU rule is that it does not satisfy the EUaxiom of Continuity (see, e.g., Bartha and DesRoches 2021). Recallfrom section 3.3 that this axiom implies that no outcome is so badthat we shouldn’t be willing to take a gamble that might resultin that outcome, provided that the gamble is sufficiently likely toinstead result in an outcome that provides an improvement on thestatus quo.

AI-Driven Decision-Making Models

Descriptive decision theory is a branch of decision theory that focuses on understanding and describing how individuals and groups actually make decisions in practice. Unlike normative decision theory, which prescribes how decisions should ideally be made, descriptive decision theory aims to study and explain the decision-making processes that people use in real-life situations. In theoretical literature, it is represented that decision theory signifies a generalized approach to decision making. It enables the decision maker to analyze a set of complex situations with many alternatives and many different possible consequences and to identify a course of action consistent with the basic economic and psychological desires of the decision maker. Despite its strengths, Decision Theory faces several challenges, including cognitive biases and the difficulty of accurately estimating probabilities. Cognitive biases can lead decision-makers to deviate from rational choices, while estimating probabilities often involves subjective judgments that may not reflect reality.

This subjective expected utility (SEU) theory has its roots in the work of Blaise Pascal, Daniel Bernoulli, Vilfredo Pareto, and Frank P. Ramsey, and finds its fullest expression in Leonard J. Savage’s Foundations of Statistics (1972). According to SEU a rational agent’s basic desires can be represented by a utility function u that assigns a real number u (c ) to each consequence c. The value of u (c ) measures the degree to which c would satisfy the agent’s desires and promote his or her aims. To apply decision theory, the business would first identify the possible outcomes and then estimate the likelihood (probability) of each. The next step would involve assessing the value (or utility) of the outcomes, taking into account both the expected benefits (like increased sales) and costs (such as investment and operational costs).

Some people find the Continuity axiom an unreasonable constraint on rational preference. Is there anyprobability \(p\) such that you would be willing to accept a gamblethat has that probability of you losing your life and probability\((1-p)\) of you gaining $10? However,the very same people would presumably cross the street to pick up a$10 bill they had dropped. But that is just taking a gamble that has avery small probability of being killed by a car but a much higherprobability of gaining $10! More generally, although people rarelythink of it this way, they constantly take gambles that have minusculechances of leading to imminent death, and correspondingly very highchances of some modest reward.

Despite this, the field is important to the study of real human behavior by social scientists, as it lays the foundations to mathematically model and analyze individuals in fields such as sociology, economics, criminology, cognitive science, moral philosophy and political science. Perhaps there is always a way to contrive decision models such thatacts are intuitively probabilistically independent of states. Recall that Savage was tryingto formulate a way of determining a rational agent’s beliefsfrom her preferences over acts, such that the beliefs can ultimatelybe represented by a probability function. If we are interested inreal-world decisions, then the acts in question ought to berecognisable options for the agent (which we have seen isquestionable). Moreover, now we see that one of Savage’srationality constraints on preference—the Sure ThingPrinciple—is plausible only if the modelled acts areprobabilistically independent of the states.

2 Cardinalizing utility

Key terms in decision theory including Acts, States of Nature, and Pay Off matrix with examples illustrating crop and market scenarios.View In the paper, the author tries to present some elements of the decision as a dynamic and very important process of private company management, as well as the concept of decision system and elements of the decision process. The complex issue raised by the adoption of a scientifically sound decision requires knowledge of the elements that must be emphasized in its elaboration.

The distinct advantage ofJeffrey’s theory is that real-world decision problems can bemodelled just as the agent perceives them; the plausibility of therationality constraints on preference do not depend on decisionproblems being modelled in a particular way. We first describe theprospects or decision set-up and the resultant expected utility rule,before turning to the pertinent rationality constraints on preferencesand the corresponding theorem. Beyond this, there is room for argument aboutwhat preferences over options actually amount to, or in other words,what it is about an agent (perhaps oneself) that concerns us when wetalk about his/her preferences over options. This section considerssome elementary issues of interpretation that set the stage forintroducing (in the next section) the decision tables and expectedutility rule that for many is the familiar subject matter of decisiontheory. Further interpretive questions regarding preferences andprospects will be addressed later, as they arise. Decision theory is based on the premise that individuals are rational decision-makers who aim to maximize their expected utility.

It presents the decision analysis process for both public and private decision making, using different decision criteria, different types of information and information of varying quality. It describes the elements in the analysis of decision alternatives and choices, as well as the goals and objectives that guide decision making. The key issues related to a decision-maker’s preferences regarding alternatives, criteria for choice and choice modes, together with the risk assessment tools, are also presented. One can assemble the available information in a form directly usable in decision-making, mathematically assess the consequences of decisions, and combine both to reach optimal decisions. This article discusses the basis of such scientific decision-making, explaining the key concepts of utility, prior information, and maximization of expected utility. Statistical decision theory enlarges the framework of decision-making to include ‘choice among statistical procedures’.

Then decision theory is concerned with assuming that thedesirability of the prize (and similarly the desirability of no prize)is independent of how the coin lands, your preference between the twolotteries should be entirely determined by your comparative beliefsfor the two ways in which the coin can land. For instance, if youstrictly prefer the first lottery to the second, then that suggestsyou consider heads more likely than tails. A common way to rationalise Allais’ preferences is that in thefirst choice situation, the risk of ending up with nothing when onecould have had $2400 for sure does not justify the increased chance ofa higher prize. Consider first an ordering over three regular options, e.g., the threeholiday destinations Amsterdam, Bangkok and Cardiff, denoted \(A\),\(B\) and \(C\) respectively. This information suffices to ordinally representyour judgement; recall that any assignment of utilities is thenacceptable as long as \(C\) gets a higher value than \(B\) which getsa higher value than \(A\). But perhaps we want to know more than canbe inferred from such a utility function—we want to know howmuch \(C\) is preferred over \(B\), compared to how much \(B\) ispreferred over \(A\).

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