7.2.1 Notation
Group Profile
Profile of the group i, also called the barycenter of the group, is a vector P i :
and in the case of standardized data, it becomes
where 
is the mean of the variable xv
for the cases belonging to the group i and
Sv is the overall standard deviation
of this variable.
- City block distance
- Euclidean distance
- Chi-square distance
where
Moreover, the program provides a possibility of using "weighted" distance, called Displacement, which is defined as follows:
The program starts using an initial classification variable defined a priori, or a random sample of cases or a stepwise sample of cases, which constitute the initial core of the groups. An iterative procedure refines the results by stabilizing the cores. The final group constitutes the categories of the classification variable. The number of typology groups may be reduced using an algorithm of hierarchical ascending classification