expected utility
Low (C2/Technical)Technical/Academic
Definition
Meaning
In decision theory and economics, a mathematical calculation of the average or mean outcome of a choice, weighted by the probability of each possible outcome, and evaluated according to the desirability (utility) of those outcomes.
The fundamental measure in rational choice theory, representing the sum of the utilities of all possible outcomes of a decision, each multiplied by its probability. It's the core criterion for maximizing rational decision-making under uncertainty.
Linguistics
Semantic Notes
This is a compound technical term. The meaning is not simply the sum of 'expected' and 'utility'. It is a precise, quantifiable construct used to model and predict choices. Often contrasted with 'subjective expected utility' which incorporates personal beliefs about probabilities.
Dialectal Variation
British vs American Usage
Differences
No significant lexical or conceptual differences. The term is identical in meaning and use across academic and professional contexts in both regions.
Connotations
Purely technical, formal, and mathematical. No regional connotative differences.
Frequency
Used with equal frequency in relevant academic fields (economics, psychology, philosophy, operations research) in both the UK and US.
Vocabulary
Collocations
Grammar
Valency Patterns
[Agent] calculates the expected utility of [Choice/Decision].The expected utility of [Option A] exceeds that of [Option B].[Subject] aims to maximize expected utility.Vocabulary
Synonyms
Strong
Neutral
Weak
Vocabulary
Antonyms
Phrases
Idioms & Phrases
- “[None - it is a technical term, not an idiom]”
Usage
Context Usage
Business
Used in risk analysis and strategic decision-making to formally evaluate investment options or projects under uncertainty.
Academic
Core concept in microeconomics, decision theory, game theory, behavioral economics, and the philosophy of rational choice.
Everyday
Virtually never used in everyday conversation. The concept might be loosely described as 'weighing the pros and cons'.
Technical
A foundational, formalized metric for modeling rational choice, central to statistical decision theory, AI (for agent design), and actuarial science.
Examples
By Part of Speech
verb
British English
- The agent is programmed to always choose the action that is expected-utility-maximising.
- We need to expected-utility-weight these potential outcomes.
American English
- The model assumes that investors expected-utility-maximize.
- A rational actor will choose to expected-utility-optimize.
adverb
British English
- [Not used adverbially]
American English
- [Not used adverbially]
adjective
British English
- The expected-utility framework dominates modern microeconomics.
- He presented an expected-utility analysis of the policy.
American English
- The expected-utility model has well-known limitations.
- Their approach is grounded in expected-utility theory.
Examples
By CEFR Level
- [Not applicable for A2 level]
- [Not applicable for B1 level]
- In simple terms, expected utility helps you make the best choice when you aren't sure what will happen.
- A good decision doesn't always have a good outcome, but it has the highest expected utility.
- The economist argued that, despite the risk, the investment had a positive expected utility when long-term social benefits were factored in.
- Critics of the model point to real-world behaviors that systematically violate the axioms of expected utility theory.
Learning
Memory Aids
Mnemonic
Imagine choosing between two bags of lottery tickets. EXPECTED UTILITY is not just counting the tickets (probability), but also checking the potential prizes on them (utility), and calculating the average prize you'd likely get from each bag.
Conceptual Metaphor
CHOICE IS A CALCULATION. The mind is a mathematician weighing future happiness.
Watch out
Common Pitfalls
Translation Traps (for Russian speakers)
- Avoid translating literally as "ожидаемая польза". The correct equivalent is "ожидаемая полезность", a direct calque of the economic term. "Польза" is too broad/general, while "полезность" is the specific economic/decision theory term for 'utility'.
Common Mistakes
- Using it as a fancy synonym for 'expectation' or 'hope' (e.g., 'My expected utility for this holiday is relaxation' – incorrect). Confusing it with 'expected value', which is the probability-weighted average of monetary outcomes, not desirability. Treating it as a plural noun ('expected utilities' is fine for multiple calculations).
Practice
Quiz
What is the primary purpose of calculating 'expected utility'?
FAQ
Frequently Asked Questions
No. Expected value is the probability-weighted average of possible *monetary* outcomes. Expected utility uses the same probability weights but applies them to the 'utility' (personal desirability/satisfaction) of those outcomes, which may not be linear with money (e.g., £1000 may not be ten times as desirable as £100).
As a precise, conscious calculation, rarely. Expected utility theory is a *normative* model (how people *should* decide rationally). *Descriptive* models (how people *actually* decide) like Prospect Theory show systematic deviations from expected utility maximization due to cognitive biases.
Yes. If the potential outcomes of a decision are predominantly undesirable, and the probability of bad outcomes is high, the calculated expected utility can be a negative number, indicating the choice is, on average, harmful or undesirable.
Two core components are needed: 1) A complete set of all possible outcomes from a decision. 2) For each outcome: a) its probability of occurring, and b) a numerical measure of its 'utility' (benefit, value, or desirability to the decision-maker). The calculation is: Sum over all outcomes (Probability of outcome * Utility of outcome).