How we change what others think, feel, believe and do
We often mistakenly assume things are correlated when they are not. When we make this mistake, we will find ways to ‘prove’ it or simply believe and assert the correlation.
This is particularly likely when the things we are correlating stand out in a distinctive way.
The opposite is an invisible correlation where an actual correlation is missed, for example the link between smoking and cancer was not realized for a long time.
Redelmeier and Tversky (1996) assessed 18 arthritis patients over 15 months, whilst also taking comprehensive meteorological data. Virtually all of the patients were certain that their condition was correlated with the weather. In fact the actual correlation was close to zero.
I meet people from around the world. One of the ways I assess people is how generous they are. I meet a person who is very generous. I like them and ask where they are from, which turns out to be Iceland. I later meet another generous person who also turns out to be from from Iceland.
I assume that most people from Iceland are, by my standards, generous.
In fact, I've spoken to many people from Iceland before who were not that generous, but I did not pay attention to their origins.
Assert correlation between the use of your product and the health, wealth and happiness of everyone who uses it.
When a correlation is asserted, ask for proof. Beware also when you find yourself finding correlation—it may have been caused by subtle manipulation of your expectations.