Note that we do not add a separate variable to measure "Specialization" and at the same time, neither is specialization the reciprocal of our "Diversity" variable.
However, measuring specialization requires detailed and quantitative descriptions of habitat requirements or resource use, which are difficult to obtain for many species.
The number of patent applications (7) and the RTA-index (0.2) which measures technological specialization were both very low in the solar energy field during the period 2000 2007 [36].
Measures of specialization mostly ignore phylogenetic relationships or ecological similarity within an association matrix.
We differentiate between species-level measures of specialization, useful to investigate variability among species within a web, and a single network-wide measure that can be used for comparisons across networks.
These findings suggest that network-wide measures of specialization, particularly H2', do not necessarily require a very large or even complete association matrix, but can also be very well estimated from a smaller representative subset as long as there is no systematic sampling bias.
Incorporating interaction frequency or even a direct measure of interaction strength in a network measure of specialization would thus provide an important progress frequently called for.
Positive values indicate greater dependence in the pollinator group and it is a measure of specialization across both trophic levels24.
In order to measure functional specialization in pollination networks, we followed the approach developed by Ref [27].
The results are robust with respect to alternative estimation method and alternative measures of industry specialization.
