How to Count to One Thousand.

An agent must verify that n objects are present. While counting, the agent might lose track and need to start over. The scheme that minimizes the expected counting time involves several layers in which objects are grouped into stacks, which are grouped into stacks of stacks, and so on. The size of each division depends only on the probability of making a mistake; the number of levels in the process increases with the logarithm of the size of the task. Variations on the model are introduced to investigate the optimal size of an organization employing presence of error-prone workers. Copyright 1992 by Royal Economic Society.