Hi everyone !

Today's subject is correlation and causation !

Correlation

Two events (let's say X and Y) are correlated if we observe a dependancy, a relation between them.
For instance : number of hair of a man has a tendency to decrease when growing older : we can say that age and number of hair are correlated !

Correlation or causation ?

A common reasoning mistake is to say: "X and Y are correlated, so X is causing Y". That way we confuse correlation and causation because in reality, it's possible that Y causes X, or that X and Y have a common cause Z, or else that X and Y are accidentely connected but without any causation link !

Some examples

• Driving a wheelchair is dangerous, because most people who drive them have had an accident.
• Average life expectancy is higher in country where we eat the more meat. Can we conclude that if you eat only meat, you will live better ?

You can found a lot more examples on the wonderful website : spurious correlation

I believe it's really important to know this because you can be tricked if you don't know !
Don't you think ? Tell me in the comments
Feel free to share, like and follow :-)