Choices and persuasion
Framing effect
The same facts lead to different choices depending on how they're described, such as a 90% success rate against a 10% failure rate.
People react to the description as well as the facts. 'Saves 200 of 600 people' and 'lets 400 of 600 die' are the same outcome, and people choose differently between them.
Framing is unavoidable: every message frames something. Choose frames that are honest and help people understand, and watch for it in research too, where the way a question is worded changes the answer.
In practice
'Free delivery on orders over £30' gets a different response from 'a £3.99 delivery charge on orders under £30', though the rule is identical.
Common mistake
Framing that leaves people with a false picture, such as quoting a monthly price for something billed yearly.
Where it comes from
Shown by Amos Tversky and Daniel Kahneman in The Framing of Decisions and the Psychology of Choice (1981), with the 'Asian disease' problem.