1.1 What is modelling?

Example: Psychology

“Psychology is the science of human behaviour. It may concern information processing in the neural system, facial expressions of emotions, the value of gossip on the shop floor, or treatment of arachnophobia. Humans are very complicated creatures and very difficult to research. For example, humans often see that they are experimental subjects and one may not break them. Many theories in psychology are therefore not very precise and clear. Yet one can occasionally construct useful and precise models. As was noted before, humans are complicated creatures, but cars are also complicated machines. Yet one can make correct predictions about improvements for traffic situations with the help of computer models in which the driver and the car are very simplified. More often psychologists use like scientists computer models, for example for modelling the spreading of fashion phenomena, stopping with smoking, and even the interaction between angry spouses.

Carrying out such simulation puts no high demands on programming skills. Also more and more user-friendly programming language have become available, also for modelling. When secondary school pupils with basic competencies in programming and modelling start with a study like psychology they cannot only implement existing computer models, but also improve them. They can almost directly start with designing and carrying out psychological experiments. Many results in psychology come from reaction time experiments in which for instance subjects must distinguish between previously learned words and new words. Because psychology is such a complicated science field, statistics is very important. Computer simulations of statistical principles and statistical methods can strongly contribute to good and quick understanding of the involved statistics.”

Han L.J. van der Maas, professor of Psychological Methods