On the Provenance of Linked Data Statistics
  As the amount of linked data published on the web grows, attempts are being made to describe and measure it. However even basic statistics about a graph, such as its size, are difficult to express in a uniform and predictable way. In order to be able to sensibly interpret a statistic it is necessary to know how it was calculate. In this paper we survey the nature of the problem and outline a strategy for addressing it. 
William Waites
cs.DB