  The use Hirsch's h-index as a joint proxy of the impact and productivity of a
scientist's research work continues to gain ground, accompanied by the efforts
of bibliometrists to resolve some of its critical issues, through the
application of a number of more or less sophisticated variants. However, the
literature does not reveal any appreciable attempt to overcome the objective
problems of measuring h-indexes on a large scale, for purposes of comparative
evaluation. Scientists may succeed in calculating their own h-indexes but,
being unable to compare them to those of their peers, they are unable to obtain
truly useful indications of their individual research performance. This study
proposes to overcome this gap, measuring the h- and Egghe's g-indexes of all
Italian university researchers in the hard sciences, over a 5-year window.
Descriptive statistics are provided concerning all of the 165 subject fields
examined, offering robust benchmarks for those who wish to compare their
individual performance to those of their colleagues in the same subject field.
