When asked to make predictions, people often select a salient (but not necessarily relevant) starting point and adjust their guesses from there. This adjustment may be insufficient. It has been found that different starting points yield different estimates that are biased towards the initial starting values. This phenomenon is called anchoring.

Starting points can be given, or they may be the result of some incomplete computation. For example, estimate within 5 seconds the product of :

8 x 7 x 6 x 5 x 4 x 3 x 2 x 1

Have another go, but this time, estimate within 5 seconds the product of:

1 x 2 x 3 x 4 x 5 x 6 x 7 x 8

Click here for the answer.