The starting point
This is the first of (at least) 3 posts on p-values. p-values are everywhere in statistics- especially in fields that require experimental design.
They are also pretty tricky to get your head around at first. This is because of the nature of classical (frequentist) statistics. So to motivate this I am going to talk about a non-statistical situation that will hopefully give some intuition about how to think when interpreting p-values and doing hypothesis testing.
My New Car
I want to buy a car. So I go down to the second hand car dealership to get one. I walk around a bit until I find one that I like.
I think to myself: ‘this is a good car’.
Now because I am at a second-hand car dealership I find it appropriate to gather some data. So I chat to the lady there (looks like a bit of a scammer, but I am here for a deal) about the car.…