REAL
Keystone sector methodology applied to Portugal
structural equivalent sets. The display of the test splits the whole set of cases into
subsets that have all positive correlation within each subgroup, and negative correlation
between the subgroups. The procedures switch the initial order and put members of the
subsets next to each other, blocking them together16.
Some of the blocks are clearly similar and substitutable entities, namely those
two we found for MONEY (private construction and insurance companies) and Banks
in Information (all the banks together in a subgroup). As we have tried to excise the top
six entities in INFORMATION and ORGANIZATION matrices we did not carry out
more excision tests by sets of entities. Trying to make some comparative statements
with the research presented in Kilkenny and Nalbart (2000) we tried to run the test with
the excision of the banking sector but it did not split the network structure. In sum,
there is no evidence for a keystone sector in TT social network, although it could be a
consequence of some noise revealed in the survey.
5. Summary Evaluation
After carrying out the empirical analysis based on the multiplex survey about
information, money and organizational support links within the town, our main findings
can be summarized as follows:
1. There are no Keystone sectors in TT, as found in various US studies. None of the
entities surveyed is decisive in the global network context; however, the private
construction and insurance firms together, act like a keystone due to the minimal
density in Money matrix.
2. Densities are substantially lower than in previous studies. This network is, then, less
likely to maintain the existent social capital, particularly in Money relations. The
textile industry is captured in Organization at the Associative level, which means
that their monetary receipts have no significant effect in the internal structure, as
predicted. This ‘cluster’ requires further study in their external links.
16 Tables for results are presented in Appendix.
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