= Hyperparameter
{tag=AI-complete}
{wiki=Hyperparameter_(machine_learning)}
A parameter that you choose which determines how the algorithm will perform.
In the case of <machine learning> in particular, it is not part of the <training data set>.
Hyperparameters can also be considered in domains outside of <machine learning> however, e.g. the step size in <partial differential equation solver> is entirely independent from the problem itself and could be considered a hyperparamter. One difference from machine learning however is that step size hyperparameters in <numerical analysis> are clearly better if smaller at a higher computational cost. In machine learning however, there is often an optimum somewhere, beyond which <overfitting> becomes excessive.