Calculate the expected value of gathering more information

Before researching further, ask whether the additional information is actually worth the cost to obtain.

Why it works

More information is not always worth its cost. The expected value of information (EVOI) is the probability that the new information would change your decision, multiplied by the gain from making the better choice. If the probability you would change your decision is low, or if the decision consequence is small, the information is worth less than the time cost of obtaining it. This prevents the common pathology of endless research to avoid deciding.

How to do it

1. Ask: "What is the chance this new information would actually change my decision?"
2. Ask: "If it did change my decision, how much better would the new choice be?"
3. Multiply those two numbers — that is roughly the value of the research.
4. Compare to the cost (time, money) of getting the information. If cost exceeds value, decide now.

Evidence

Expected value of information is a formal concept in decision analysis and Bayesian statistics. Its practical use as a stopping rule for research is established in management science; the formal EVOI calculation was developed in operations research. (mechanistic)

EVOI calculations require probability estimates that are often unavailable; even a rough approximation ("low," "medium," "high") captures most of the insight.

Common mistake

Continuing to research because "there might be something important I don’t know yet," without ever asking whether the odds of that something materially affecting the decision are worth the cost.