– Finds clusters that minimize or maximize an objective function.
– Enumerate all possible ways of dividing the points into clusters and
evaluate the `goodness' of each potential set of clusters by using
the given objective function. (NP Hard)
– Can have global or local objectives.
Hierarchical clustering algorithms typically have local objectives
Partitional algorithms typically have global objectives
– A variation of the global objective function approach is to fit the
data to a parameterized model.
Parameters for the model are determined from the data.
Mixture models assume that the data is a ‘mixture' of a number of
statistical distributions.