The goal of these notes is to enable the reader to "extract information" from experimental data. The more ambitious goal would be to develop in the reader the skeptical attitude that allows one not to fall in the trap so sharply summarized by the Feynman's quote above.
Our main concern will be the understanding of the methods used to analyse data in physics experiments and avoid to come to wrong conclusions because blindly applying recipes.
All numbers have to make sense !
More generally, the idea of analysing data means understanding the world and take informed decisions. We leave our lives submerged in data. Newspapers, TV programs, social media, they all present us an immense amount of data. Often (...always) they are accompanied by some pre-digested interpretation. The data are the data.
Bob Woodards said: "Everyone has their own version of the truth, but there are facts". If you know where the data are coming from, under what conditions they were taken (something much easier in science than elsewhere), you can learn to read them and build your own interpretation and compare or even challenge the predigested one.