Statistics is subjective… always!

From time to time you listen to talks and in a moment you do not expect any surprises you hear the argument that statistics is objective. It is often used to strengthen other arguments and tries to prevent doubts in them. Much to often statistics is given a credibility it does not deserve and so the times it gets usefully applied get devalued. With this in mind, one thing have to be clear: Statistics is subjective…. always!

Quite often the words on objectivity are used in haste, often also from scientists who should know it better. Many arguments on the objectivity of statistics comes from the past, where frequentist statistics was the norm and its application for nearly every problem was seen as appropriate and therefore objective. But many forget, that by using frequentist statistics they make a choice. A choice on assumptions many have learnt years ago and are long forgotten.

May it be an assumption on normal distributions, on stationarity or ergodicity. Let’s be honest, those are never fulfilled, but always accepted indirectly by choosing a standard methodology. And when you doubt that you have a choice on your statistical methodology, then the answer is in nearly ever case that there is one. You do not have to go all the way to Bayesian statistics, there are many steps in between. The start is usually to think about the assumptions you are currently making in your methodology and then go the extra step to think what happens when one of these fails.

Most important is that we start to teach the students that statistics is based on assumptions. For myself it is a game of assumptions and usually you have a lot of freedom to make them. That does not mean that standard methods should not be taught, yes, for everyone who works in geoscience a foundation in statistical techniques is necessary. But it is important at the same time that we make clear that each methodology has its disadvantages and that alternatives exist. They are not necessarily easily to calculate, but they are certainly at least some seconds worth to think about.