So when we have low probability events that we’re trying to get people to take precautions against, such as when we’re selling insurance packages, we’re much more likely to get a better response if we say “3 out of a 100 businesses experience this” rather than saying “3 percent of businesses.” Subjectively, audiences relate much more to the first statement.

On the flipside, we want to downplay the downside of an essential operation where a doctor needs to disclose risk, but you don’t want a person stressing out as that can cause even more problems. Here, operation risks are best disclosed as percentages vs frequency if we want to keep patients informed but calm. For example, “Only .003% have complications” vs “3 in every 100,000 have complications”. The same information is experienced very differently by most people.