it is interesting that the most popular number is 7. unfortunately the author didn't explain why. However maybe not everything has a reasonable reason.
Wouldn't it be interesting to go further than "what is your favourite number?" and find out why people claim 7 is their favourite number?
I'd be interested in anything that tests whether 7 actually is a preferred number in real situations rather than just the number that people say when asked.
In some cultures 7 is told to be a lucky number. Perhaps people internalize that after hearing it many times and start to prefer this particular number.
