Observe data collection at the moment of measurement See, observe, learn how data are collected at moment and place of measurement. "You never learn more about a process than when you directly observe how data are actually measured," said Cuthbert Daniel, a superb applied statistician. See with fresh eyes. Walk around what you want to learn about. Talk to those who do measurements. See how numbers came to be. Do those measuring know the desired answer? Are those measuring skilled, alert, honest, biased, incompetent, sloppy, tired and emotional?...Artifacts and errors in measurements measured? How are outliers adjudicated? Edward Tufte, Seeing With Fresh Eyes uxmeasurement
You cannot consume what is not produced The only law of economics that I believe in is Hamming’s law: “You cannot consume what is not produced.” There is not another single reliable law in all of economics I know of which is not either a tautology in mathematics or else sometimes false. Richard Hamming, The Art of Doing Science and Engineering: Learning to Learn Scientific writing economics