🧠 Cognitive · Bias

Anchoring: The First Number Determines Everything

Kahneman & Tversky 1974 — irrelevant numbers shape every judgment

📅 1974 🔬 Daniel Kahneman & Amos Tversky 🏛 히브리 대학교 / 스탠포드
⚡ TL;DR
Kahneman and Tversky spun a rigged roulette wheel that landed on 10 or 65, then asked subjects "What percent of UN countries are in Africa?" The 10-group averaged 25%, the 65-group 45%. A completely irrelevant number anchored every estimate. Their 1974 Science paper toppled the rational-actor model and won Kahneman the 2002 Nobel.

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⚓ 닻 효과: 당신의 판단을 조종하는 첫 숫자의 비밀 #Shorts
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Intentionally Irrelevant Numbers

The genius of the experiment's design was in the roulette wheel itself: it was rigged to stop only at 10 or 65. Participants were simply told that the number was 'randomly determined'. Immediately afterward, they were asked to estimate the percentage of African countries in the UN. Even though participants knew the number was clearly irrelevant to the answer, the initial number pulled their responses towards it. The key finding was that awareness of the irrelevance did not eliminate the anchoring effect. This demonstrated the powerful, often subconscious, influence of an initial anchor, regardless of its perceived connection to the actual question.

Overwhelming Influence in Negotiation, Pricing, and Courts

Hundreds of subsequent studies followed, revealing the pervasive nature of anchoring. For instance, when real estate agents were shown the same house but given different listing prices, their appraisals shifted accordingly – demonstrating that even experts are swayed by an anchor. Judges also exhibited anchoring to the sentences requested by prosecutors. The adage, 'He who names the price first in a negotiation wins,' was thus scientifically proven. This phenomenon also explains why Tesla's Model S price is often displayed next to the more expensive Model X, and why the most expensive wine on a menu is rarely intended to be sold, but rather to serve as an anchor, making other options seem more reasonable.

Escaping the Anchor

Daniel Kahneman himself acknowledged in his 2011 book, *Thinking, Fast and Slow*, that the anchoring effect is difficult to avoid, even when consciously recognized. He suggested that 'deliberately thinking in the opposite direction' can offer a partial defense. Practical strategies include setting one's own anchor before a negotiation and avoiding immediate responses after an opponent's anchor is presented, instead taking time to deliberate. However, complete prevention remains impossible, as System 1, or fast thinking, is the human default mode of cognition, making us inherently susceptible to these initial influences.

First Impressions Through Hanja

The Chinese character '初' (chō, meaning 'first' or 'beginning') is composed of the radicals for 'clothing' (衤) and 'knife' (刀), depicting the act of cutting fabric for the very first time. This character embodies the profound insight that 'the very first cut of the scissors determines the entire shape of the garment.' The essence of the anchoring effect, therefore, is precisely contained within this ancient character. Three millennia before Daniel Kahneman scientifically demonstrated the anchoring effect in 1974, the wisdom embedded in Hanja already understood that the initial decision shapes everything that follows.

🌍 Real-world Impact 협상·가격 책정·면접·법정 형량·정책 발표·SNS 첫인상 — 거의 모든 결정. (KR)
⚠️ Controversy & Replication 재현성 위기 (2010s replication crisis) 후 효과 크기가 일부 study에서 절반으로. 그러나 mega-analysis에선 robust. (KR)
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