In past issues of Negotiation, we’ve reviewed the anchoring effect – the tendency for negotiators to be overly influenced by the other side’s opening bid, however arbitrary. When your opponent makes an inappropriate bid on your house, you’re nonetheless likely to begin searching for data that confirms the anchor’s viability. This testing is likely to affect your judgment – to the other party’s advantage.

Psychologists Amos Tversky and Daniel Kahneman identified the anchoring effect in 1974. Participants watched a roulette wheel that, unknown to them, was rigged to stop at either 10 or 65, the estimated the number of African countries belonging to the United Nations. For half of the participants, the roulette wheel stopped on 10. They gave a median estimate of 25 countries. For the other half, the wheel stopped on 65. Their median estimate was 45 countries. The random anchors dramatically affected judgment.