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Rather, clustering analyzes the data on an ordinal scale
(Hartigan, 1975). Cluster analysis has been recommended for
studies of semantics (Miller, 1969; Rapopart & Fillenbaum,
1972; Friendly, 1977). It is important to note that with
cluster analysis, as with factor analysis, there are no best
or unique solutions.
For the data of each of the four judgement schemes,
distance matrices were generated by averaging the absolute
difference between the mean scores for each subject for all
pairings of criteria. (See Appendix M for a listing of the
program for generating the distance matrices.) Cluster
analysis was done with BMDP sub-program P1M (Hartigan,
1981). The clustering method used was complete linkage.
With complete linkage, the distance between any two clusters
is the largest distance between pairs of criteria in each of
the CLGSLETT. Complete linkage produces compact clusters
and avoids the chaining effects common with single linkage
(Mardia, Kent & Bibby, 1979). In a study of semantics using
cluster analysis, Miller (1969) found no significant
differences between single and complete linkage. The
results of the four cluster analyses appear as dendrograms
in.Figures 10, 11, 12, and 13.
Operationally, in this case, cluster analysis is a
systematic examination of the mean absolute differences