Combinatorial Aspects of the Distribution of Rough Objects
  The inverse problem of general rough sets, considered by the present author in some of her earlier papers, in one of its manifestations is essentially the question of when an agent's view about crisp and non crisp objects over a set of objects has a rough evolution. In this research the nature of the problem is examined from number-theoretic and combinatorial perspectives under very few assumptions about the nature of data and some necessary conditions are proved. 
A. Mani
cs.AI cs.IT math.CO math.IT math.LO