What Even Are Statistics Tables

So, I am not an statistician. And as such, I fear statistics. In particular the I fear the topics I was taught to just follow without any satisfying explanation. Among those monsters of the dogma of university level statistics, there is a selected group that used to terrify me in such a way that is hard to explain. That if you asked me before what in the world were the statistical tables, I would have made the sign of the cross, ran away and never talk to you again.

However, recently I was deeply humiliated by somebody posing a question asking me to compute who knows what in order to do a Pearson’s chi-squared test. Naturally, at the moment I fled away, because I had absolutely no idea who Pearson was, and how they got their hands on one of my favourite letters of the Greek alphabet and converted in a synonym of madness.

After showing my deep ignorance about basic statistics I decided to go and revisit my course of statistical methods that I took about seven years ago —when I was a bright eyed youngster with dreams of grandeur—, and turns out it’s not too bad. But when I was studying this, my greatest foe showed up. The dreaded Table A4 from A Basic Course in Statistics, 5th edition by Clarke and Cooke. And the ever present question during my second year on my engineering degree popped to my mind again

What in the world are the entries of that table?