Where does the p value come from?

Question

So i know the value needs to be ‘satistically significant’ for an experiment to be valid and that the variable chosen is explaining the outcome.

I also know it needs to be p<0.05 so you know it’s above the 95% confidence interval and that the value chosen is explaining the outcome. And you can have smaller p values like p<0.01 = 99% which is even stronger evidence.

But how does it work? Why does a calculation given you that certainty? And how was it decided that 0.05 is the point when the value becomes statistically significant? And to lead on from that, if there is a clear relationship between 2 variables, you have to ignore it if its only 90%.. Im just confused on the background of the of thr p value.

In: Mathematics

Answer 1

[deleted]