The Sampling, By Quadrats, of Planar Aggregates

The estimation, for planar particle aggregates, of their number or density per unit area and of their distributions (e.g. of area or perimeter), by means of randomly placed quadrats, is complicated by the question of deciding whether or not to include particles truncated by the quadrat boundaries. Previous unsatisfactory solutions to this problem have led to unnecessary bias in the estimates. A general ‘associated point’ solution is presented, and its theory is developed in some detail.