The world's most famous advertising experiment never happened.
In 1957 James Vicary claimed flashed messages in a Fort Lee cinema raised popcorn sales by 57.5 and Coca-Cola sales by 18.1 percent among 45,699 viewers. In 1962 he admitted to Advertising Age that the whole thing was a gimmick to rescue his failing business.
Useful: A spectacular number with no published study behind it is just a claim.
Source: en.wikipedia.org