Here come two resources to help understand the resemblances and differences among indexes to measure the Information Society.
The first one:
is a comparison of all (or almost, who knows one year after) the existing indexes
The second one:
If you need to cite this article in a formal way (i.e. for bibliographical purposes) I dare suggest:
Peña-López, I. (2006) “Information Society indexes” In ICTlogy,
#33, June 2006. Barcelona: ICTlogy.
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