Shape parameter

For example, "peakedness" refers to how round the main peak is.

[3] Many estimators measure location or scale; however, estimators for shape parameters also exist.

Estimators of shape often involve higher-order statistics (non-linear functions of the data), as in the higher moments, but linear estimators also exist, such as the L-moments.

The following continuous probability distributions have a shape parameter: By contrast, the following continuous distributions do not have a shape parameter, so their shape is fixed and only their location or their scale or both can change.

It follows that (where they exist) the skewness and kurtosis of these distribution are constants, as skewness and kurtosis are independent of location and scale parameters.