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Imprecise probability

Represent incomplete probabilistic commitment by a coherent set of admissible probability measures or equivalent lower and upper expectations, so conclusions expose a range and distinguish robust agreement from decisions that depend on an unresolved model choice.

Version
v2 · 2026-08-30 · History
Domain-specific #
2047
Origin domain
probability and decision theory
Subdomain
imprecise uncertainty models

Core Idea

Imprecise probability is a family of uncertainty models that permits a set of probability measures or noncoincident lower and upper probabilities or expectations instead of forcing one fully specified additive distribution; envelope models use \(\underline P(A)=\inf_{P\in\mathcal K}P(A)\) and \(\overline P(A)=\sup_{P\in\mathcal K}P(A)\) for a credal set \(\mathcal K\). partial commitments define a feasible family of precise laws, and lower and upper envelopes propagate the least and greatest compatible expectation through queries; a narrow interval records strong consensus, a wide interval records unresolved alternatives, and robust conclusions are those shared across the admissible family.

Scope of Application

Imprecise probability applies when the analyst can specify a measurable possibility space, a nonempty class of admissible probability measures or assessments, and events, gambles, or random quantities evaluated relative to that class and establish that the model intentionally leaves at least some probabilistic quantities non-singleton while satisfying its declared consistency or coherence conditions and preserving the set, envelope, or behavioral semantics used for updating and decision. The entry maps a family of formal models rather than declaring one universally correct interpretation or decision criterion; each application must state its consistency, updating, dependence, and action conventions.

Clarity

A clear claim names the carrier, governing rule, assumptions, and recognition test. This matters because imprecise can be mistaken for inaccurate, numerically rounded, statistically estimated, or poorly measured, whereas the technical identity is a deliberate set-valued or lower-upper representation of probabilistic commitment. The disciplined statement is that the object counts as Imprecise probability exactly when the model intentionally leaves at least some probabilistic quantities non-singleton while satisfying its declared consistency or coherence conditions and preserving the set, envelope, or behavioral semantics used for updating and decision

Manages Complexity

The abstraction compresses credal sets, lower and upper probabilities, lower previsions, interval probabilities, probability boxes, belief functions, random sets, possibility measures, robust Bayesian classes, and sets of desirable gambles into a stable carrier, rule, invariant, and failure boundary. It makes comparison tractable while retaining the variables that control validity.

Abstract Reasoning

  1. Type the carrier. Establish a measurable possibility space, a nonempty class of admissible probability measures or assessments, and events, gambles, or random quantities evaluated relative to that class and reject examples from a different problem. 2. Lock the rule. Express that the model intentionally leaves at least some probabilistic quantities non-singleton while satisfying its declared consistency or coherence conditions and preserving the set, envelope, or behavioral semantics used for updating and decision independently of one notation or implementation.

Knowledge Transfer

Transfer within probability and decision theory is strong when new cases preserve the same carrier, mechanism, and diagnostic. The move from A closed convex credal set K contains every probability distribution satisfying declared linear constraints, and event A receives the interval formed by the minimum and maximum of P(A) over K. to A probability-box model bounds an uncertain cumulative distribution between lower and upper cumulative functions and propagates those bounds through a system model. demonstrates that continuity.

Relationships to Other Abstractions

Local relationship map for Imprecise probabilityParents appear above the current abstraction, mutual partners to the right, and children below. Node labels state whether each abstraction is prime or domain-specific; colors identify relation types.Imprecise probabilityDOMAINPrime abstraction: Probability — is a kind ofProbabilityPRIME

Current abstraction Imprecise probability Domain-specific

Parents (1) — more general patterns this builds on

  • Imprecise probability is a kind of Probability Prime

    The proposed strict upward parent is prime:probability.

Hierarchy paths (2) — routes to 2 parentless roots

Neighborhood in Abstraction Space

Imprecise probability sits in a sparse region of the domain-specific corpus (60th percentile for distinctiveness): few abstractions share its structure, so a faithful description tends to retrieve it precisely.

Family — Imprecise Probability & Multiple Testing (5 abstractions)

Nearest neighbors

Computed from structural-signature embeddings · 2026-09-08