https://cognitive-biases.github.io/Reviewed research notes and monthly evidence updates on cognitive biases, decision making and decisions made with AI.enSat, 05 Sep 2026 00:00:00 GMThttps://cognitive-biases.github.io/research/digests/2026-08/https://cognitive-biases.github.io/research/digests/2026-08/Sat, 05 Sep 2026 00:00:00 GMTMonthly research digestAugust research covers anchoring in AI evaluation, the strength and limits of repetition-based truth judgments, and evidence transfer across domains.https://cognitive-biases.github.io/research/illusory-truth-where-repetition-stops-working/https://cognitive-biases.github.io/research/illusory-truth-where-repetition-stops-working/Sat, 05 Sep 2026 00:00:00 GMTResearch noteA large 2026 meta-analysis supports a reliable average illusory truth effect, while newer preregistered experiments show an important boundary: repeating social-political opinions did not meaningfully increase their truth ratings.https://cognitive-biases.github.io/research/prior-scores-can-contaminate-ai-judges/https://cognitive-biases.github.io/research/prior-scores-can-contaminate-ai-judges/Sat, 05 Sep 2026 00:00:00 GMTResearch noteA recent large LLM-as-a-judge study suggests that previous evaluation scores can shift later ratings even when the evaluated text is unchanged.https://cognitive-biases.github.io/research/anchoring-ai-assisted-decisions-first-number/https://cognitive-biases.github.io/research/anchoring-ai-assisted-decisions-first-number/Tue, 18 Aug 2026 00:00:00 GMTResearch noteAnchoring is strongly supported in human numerical judgment, and newer studies show two AI-related risks: people can anchor on AI recommendations, while model outputs can also shift when prompts contain numerical anchors.https://cognitive-biases.github.io/research/availability-heuristic-vivid-does-not-mean-common/https://cognitive-biases.github.io/research/availability-heuristic-vivid-does-not-mean-common/Tue, 18 Aug 2026 00:00:00 GMTResearch noteAvailability is a useful shortcut when accessible examples track real frequency. It becomes misleading when accessibility comes from non-diagnostic causes, and some popular claims about dramatic media risks and ease of retrieval are less universal than textbook examples suggest.https://cognitive-biases.github.io/research/confirmation-bias-is-more-than-seeking-agreeable-information/https://cognitive-biases.github.io/research/confirmation-bias-is-more-than-seeking-agreeable-information/Tue, 18 Aug 2026 00:00:00 GMTResearch noteConfirmation bias is a broad family of belief-consistent information-processing tendencies. Classic hypothesis-testing work also shows why a narrower problem matters: a test can fit the favored hypothesis while offering little information against plausible alternatives.https://cognitive-biases.github.io/research/continued-influence-corrections-misinformation/https://cognitive-biases.github.io/research/continued-influence-corrections-misinformation/Tue, 18 Aug 2026 00:00:00 GMTResearch noteCorrections usually improve factual accuracy, but old misinformation can still influence later reasoning. That continued influence is not the same as a backfire effect, and the distinction changes how corrections should be evaluated.https://cognitive-biases.github.io/research/curse-of-knowledge-experts-beginners-feedback/https://cognitive-biases.github.io/research/curse-of-knowledge-experts-beginners-feedback/Tue, 18 Aug 2026 00:00:00 GMTResearch noteOnce you know an answer, your own knowledge can distort estimates of what another person knows. The most useful correction is not 'explain more simply' in the abstract, but feedback from the less-informed person's actual perspective.https://cognitive-biases.github.io/research/decoy-effect-pricing-choice-sets/https://cognitive-biases.github.io/research/decoy-effect-pricing-choice-sets/Tue, 18 Aug 2026 00:00:00 GMTResearch noteAdding an inferior option can change the choice between stronger alternatives, but not every three-tier pricing table creates a reliable decoy effect. The position of the options, prior preferences and the decision context all matter.https://cognitive-biases.github.io/research/defaults-status-quo-preference-choice-architecture/https://cognitive-biases.github.io/research/defaults-status-quo-preference-choice-architecture/Tue, 18 Aug 2026 00:00:00 GMTResearch noteDefaults often change what people choose, but staying with a pre-selected or existing option does not by itself show strong preference. The useful question is what made the option sticky and whether the result still serves the person's goals.https://cognitive-biases.github.io/research/dunning-kruger-effect-what-research-shows/https://cognitive-biases.github.io/research/dunning-kruger-effect-what-research-shows/Tue, 18 Aug 2026 00:00:00 GMTResearch noteThe Dunning–Kruger Effect is better understood as a question about calibration between performance and self-assessment than as the internet rule that incompetent people are always extremely confident.https://cognitive-biases.github.io/research/framing-effect-not-all-frames-are-the-same/https://cognitive-biases.github.io/research/framing-effect-not-all-frames-are-the-same/Tue, 18 Aug 2026 00:00:00 GMTResearch noteRisky-choice framing is a robust finding, but the word 'framing' covers several different research paradigms. Treating every positive-versus-negative message as the same effect hides important differences in evidence and mechanism.https://cognitive-biases.github.io/research/hungry-judge-effect-what-study-actually-shows/https://cognitive-biases.github.io/research/hungry-judge-effect-what-study-actually-shows/Tue, 18 Aug 2026 00:00:00 GMTResearch noteThe famous parole-board study found a strong sequence pattern around food breaks, but it did not measure hunger or randomly manipulate meals. Later critiques and simulations provide plausible alternative explanations for part of the striking result.https://cognitive-biases.github.io/research/llm-cognitive-biases-what-recent-research-shows/https://cognitive-biases.github.io/research/llm-cognitive-biases-what-recent-research-shows/Tue, 18 Aug 2026 00:00:00 GMTResearch noteRecent studies make a stronger case that LLM outputs can show repeatable decision patterns that resemble named cognitive biases. They also show why we should be careful with the label: the effects depend on the task, model, prompt and conversational context, and a debiasing prompt that helps one kind of task can hurt another.https://cognitive-biases.github.io/research/loss-aversion-how-large-and-how-robust/https://cognitive-biases.github.io/research/loss-aversion-how-large-and-how-robust/Tue, 18 Aug 2026 00:00:00 GMTResearch noteLoss aversion is one of the best-known ideas in behavioural economics, but recent meta-analyses disagree substantially about its average size and about which experimental designs provide clean evidence for it.https://cognitive-biases.github.io/research/planning-fallacy-project-estimates-outside-view/https://cognitive-biases.github.io/research/planning-fallacy-project-estimates-outside-view/Tue, 18 Aug 2026 00:00:00 GMTResearch noteResearch supports a recurring pattern of optimistic completion-time estimates. The useful response is to compare the plan with similar completed work and keep uncertainty visible, not to multiply every estimate by one fixed number.https://cognitive-biases.github.io/research/sunk-cost-escalation-why-past-spend-is-only-part/https://cognitive-biases.github.io/research/sunk-cost-escalation-why-past-spend-is-only-part/Tue, 18 Aug 2026 00:00:00 GMTResearch notePast, unrecoverable costs can influence whether people continue, but escalation of commitment is a broader process. Responsibility for the original choice, completion pressure, project structure and advice can also shape the next investment.https://cognitive-biases.github.io/research/surrogation-when-a-kpi-starts-replacing-the-goal/https://cognitive-biases.github.io/research/surrogation-when-a-kpi-starts-replacing-the-goal/Tue, 18 Aug 2026 00:00:00 GMTResearch noteSurrogation is more specific than the slogan 'what gets measured gets managed.' Research in strategic performance systems shows how a measure can start to stand in for the construct it was designed to represent, and how decision processes can reduce that substitution.https://cognitive-biases.github.io/research/systematic-bias-why-more-data-is-not-enough/https://cognitive-biases.github.io/research/systematic-bias-why-more-data-is-not-enough/Tue, 18 Aug 2026 00:00:00 GMTResearch noteSystematic bias is not one mental shortcut. It is a measurement and statistical problem: a process can keep pushing results away from a target in a consistent direction, and collecting more data from the same biased process does not automatically fix it.https://cognitive-biases.github.io/research/why-the-past-can-look-better-than-it-was/https://cognitive-biases.github.io/research/why-the-past-can-look-better-than-it-was/Tue, 18 Aug 2026 00:00:00 GMTResearch noteSeveral different processes can make past periods look better from the present, but they should not be collapsed into one universal bias. Event recollection, changing emotional intensity, exposure to current negative information, and real historical trends need separate evidence.