ation. For instance, during a particular prediction, Paul might initially go for the box on the left, but then a ray of sunlight hits the box on the right, leading Paul to open that box first. Such small events can be considered a source of random noise in the experiment, that lead to variability in Paul’s behaviour, and ultimately to variability in the correctness of his predictions. As a concept, the purpose of the DGP is to describe all such sources of variability as they impact the variability of a pa