Source: Authors’ own calculations based on the IEA (2009a, 2009b). The percentages in the
first column show the weight of inter-group inequality in global inequality, while in the remaining
columns the weight of the different components in inter-group inequality is given.
From the above it is evident that inter-group inequality is more important than
intra-group inequality for the world regions considered. The weight of the former
varies between 60 and 70%, being at around 60% at the beginning and at the
end of the period (first column of Table 3). This high weight of the inter-group
component suggests that the group classification operated —according to
economic and geographic criteria— happens to be quite relevant in explaining
existing differences among countries8.
Again, the final energy consumption per GDP unit component (Tw) is the most
relevant in explaining such differences. Its relative weight is even greater than
what was recorded for global inequalities, being above 100% throughout the
period. As in the global inequality, the reduction in disparity by 51.9% is
fundamentally due to the reduction in final energy consumption inequalities per
GDP unit. This reduces by 62.6%.
The transformation index plays a limited role with a 3.5% contribution. It follows
the same downward tendency as the final energy consumption component. In
contrast, the behaviour of the interaction component is quite remarkable. This
changes sign by 1990. That is, contrary to the global inequality case, since
1995 there is a positive correlation between transformation efficiency and final
energy consumption. And this reinforces both inter-group inequalities.
Table 4. Multiplicative factorial decomposition of intra-group global
inequalities of energy intensity.
8 In fact, the weight of the intra-group component in global inequality can be construed as an
indicator of the induced error due to this type of aggregation, with a regional and economic
criterion (Esteban et al., 1999).
12