Decision skill

Decision making under uncertainty

Make useful choices when outcomes are not known and one number, story or recent event can pull judgment too strongly.

Learning outcome: You can make a decision without pretending uncertainty has disappeared.

When it matters

Notice the situation before naming the bias.

Practice the skill

Use a better reasoning move.

Decision contexts

Apply the skill to real kinds of decisions.

Evidence-reviewed lenses

Patterns worth checking, not labels for people.

Several patterns can fit the same situation. Use these lenses to ask better questions, then inspect the evidence behind each concept.

Anchoring Effect

Anchoring is a well-supported effect in which an initial numerical value can pull a later estimate toward it. A 2026 meta-analysis covering 2,601 effect sizes found a large overall effect, but also substantial variation across studies. The effect should not be treated as a rule that every number changes every judgment: incidental anchors, anchors from a different dimension, clearly random values, incentives, and some debiasing conditions were associated with smaller or null effects.

well-supported for numerical judgments; strength depends on anchor type and context Read evidence review

Subadditivity Effect

People often give a larger total probability when an event is unpacked into separate possibilities than when the same event is judged as one packed category. The effect is not universal: how the possibilities are described and how typical they are can change or even reverse an unpacking effect.

established with boundary conditions Read evidence review

Availability Heuristic

Availability is a judgment heuristic: people can use how easily examples or scenarios come to mind when estimating frequency or probability. That shortcut is not automatically an error because memorable or accessible examples can correlate with real frequency. Bias appears when accessibility is driven by factors that are not diagnostic of the quantity being judged.

established heuristic; bias is context-dependent Read evidence review

Escalation of Commitment

Sunk-cost effects and escalation of commitment overlap but are not interchangeable. Sunk-cost research asks whether irrecoverable prior investments influence current choices. Escalation of commitment describes persistence or additional resource allocation to a failing course of action and can also be driven by personal responsibility, self-justification, project structure, and other factors.

established, but related constructs should be separated Read evidence review