Classical clustering techniques are well known. They allow the classification of a number of observations into a few groups on the basis of their characteristics.
The classifications that result have a number of weaknesses:
They are black and white
They often use restricted amounts of information
It can be hard to produce a sensible classification
Volterra has carried out a lot of empirical work applying clustering techniques using fuzzy logic. These include:
Allow overlap between different segments
Can handle more useful information
Generally produce fewer segments
Provide a sense of the strength of the difference between groups
Can analyse how much change is necessary for an individual observation to move to a different category
The techniques are relevant to a number of commercial applications and have also been used to analyse university performance for the Times Higher Educational Supplement. Work using fuzzy clustering includes: Economic Geography of Great Britain, Retail Locations, Universities, Social & Economic Structure of the South East.