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Ultimatum Game

People do not necessarily accept every positive outcome when they perceive the allocation as unfair or illegitimate.

In the Ultimatum Game, one player proposes a division and the other can accept or reject it. If rejected, neither receives any of the amount being divided. Behaviour also depends on preferences, expectations and context.

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Research statusResearch in preparation
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AI relevanceAI may amplify an existing effect
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Core ideaFairness / costly veto
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Evidence baseSources and limitations summarised; independent review pending.
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Case typeBehavioural economics game
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In one sentence

People do not necessarily accept every positive outcome when they perceive the allocation as unfair or illegitimate.

The storyHow the case arises and how it can mislead our thinking.

A proposer divides a sum of money; the responder may accept or eliminate the entire payoff by refusing. Very low offers are regularly rejected in experiments, despite the loss of a positive payoff.

What do we know?Evidence, research, critical insights and what remains unknown.

The paradigm is highly mature, with cultural and contextual variation. No single fairness mechanism explains all rejection behaviour.

What is the mechanism?Which explanation best fits what we observe.

Costly veto power combined with social preferences, expectations and norm enforcement may constrain unequal offers.

What does AI change?How AI may amplify the mechanism or make it visible.

AI transfer to investigate: Human–algorithm framing, perceived agency and training consequences may influence acceptance. The fairness mechanism itself is old.

What do we want to test?The specific question we want to investigate further.

Proposed test, not yet conducted: Hold the allocation constant and vary agency (human/AI), the beneficiary, and whether rejection is framed as a training signal for AI. Measure acceptance, fairness and legitimacy.

What do we take away?What this case provisionally means — and where its limits lie.

Descriptive rejection preferences do not constitute a complete normative theory, but they are important evidence about legitimacy and acceptance.

Rejection means neither player receives anything from the amount being divided. Observed rejection can have several motives and does not establish a universal fairness norm.

SourcesPrimary and key scholarly sources.

Güth, Schmittberger & Schwarze (1982), An experimental analysis of ultimatum bargaining — Journal of Economic Behavior & Organization 3:367–388

Henrich et al. (2005), Economic man in cross-cultural perspective: Behavioral experiments in 15 small-scale societies — Author manuscript pp.5–6 game/payoffs; pp.14–17 cross-cultural results and Table 2

The full text of Güth et al. (1982) was not available for this account. Henrich et al. (2005, author manuscript pp. 5–6 and 14–17) serves as an additional primary study of game rules and cultural variation. The proposed AI application has not been independently tested.

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