OECD Culture and Local Development.pdf - PACA

ANNEX 2
The first stage, then, is to construct correlation matrices. Their number will depend
on the type of indicators (jobs or firms) and of reference territories (regions, cities
etc.). These matrices provide correlation coefficients: coefficients of + 1 reflect
maximum synergies and coefficients of - 1 imply the weakest linkages. We cannot expect
to find coefficients that are too high, and so we will look first for intersectoral linkages
with coefficients of at least 0.9, then 0.8, 0.7 and so on.
Having identified clusters of two or three sectors of activity that, at the national
level, show positive interdependence ratios, we then look for territories that meet
these hypotheses as a minimum. For this, we have indices of concentration by activityterritory.
This index gives the ratio between the proportion of a cultural sector for a
territory and its proportion for the whole economy. If the ratio exceeds 2, the
concentration is considered significant, and if it exceeds 4, it is considered very
strong.
When these clusters involve only two sectors, those two sectors within the territory
must show significant concentration if the territory is to be considered a district. For
other clusters, consisting of a greater number of sectors, the concentration rule can
be relaxed. In effect, the correlation coefficients underestimate the existence of
intersectoral links, which would show up only rarely at the territorial level, and so it
is better not to discard potential districts. At this point, some clusters are regrouped
if they are found within the same units of territories, on the condition that the
correlation coefficients are greater than 0.5
We can now go on to describe the district more precisely, the using the analysis
of concentrations in terms of enterprises, jobs, etc. Table 1 shows this approach as
applied to France in 2003.
186 CULTURE AND LOCAL DEVELOPMENT - ISBN 92-64-00990-6 - © OECD 2005