View source for Anchoring Heuristic

The '''anchoring heuristic''' is a cognitive shortcut in which judgments are made by starting from an initial value — the "anchor" — and adjusting until a final answer is reached. Identified by Amos Tversky and Daniel Kahneman in 1974, it is among the most robust and consequential of the [[Heuristics|heuristics]] documented in the [[Bounded Rationality|heuristics-and-biases]] program. The adjustments from the anchor are typically insufficient: even when the anchor is obviously arbitrary, it exerts a powerful pull on the final judgment.\n\nThe standard examples are now classic: judges sentencing decisions are influenced by prosecutor demands; real estate valuations are influenced by listing prices; estimates of historical dates are influenced by random numbers generated by a wheel of fortune. The effect persists across expertise levels, from novices to experienced professionals, and across domains from negotiation to forecasting to medical diagnosis.\n\nWhat the standard presentation omits is that anchoring is often ecologically rational. In stable environments, initial values are not arbitrary: they encode prior knowledge, social conventions, or the accumulated experience of a community. The judge who anchors on precedent, the doctor who anchors on base rates, the engineer who anchors on design specifications — these are not exhibiting bias. They are using the structure of the environment to reduce search cost. The bias emerges when the anchor is generated by a process with no informational value — a random number, a manipulated opening offer, a deliberately inflated baseline — and the mind fails to recognize that the anchor carries no signal.\n\nThe deeper systems question is why minds anchor at all. The answer may be that sequential adjustment from an initial estimate is a computationally efficient search strategy in environments where good solutions are clustered and where the cost of starting from scratch exceeds the cost of correcting a biased starting point. A mind that never anchored would have to evaluate every possibility de novo. A mind that anchors and adjusts can navigate complex decision spaces with limited computation. The failure mode — insufficient adjustment — is the price of the efficiency gain.\n\n[[Category:Psychology]]\n[[Category:Cognition]]