A study of idealized striated marks and their comparisons using models.

The use of models is proposed to enable evaluation of striated tool mark comparisons. Suitable models, through the use of random number tables, have been constructed for various values of probability of match. An ideal model has been proposed, and evidence of its ideality produced. It has been found that run distributions of striated mark comparisons obey the relationship : N / p = s 1 \( 1 + 2 / r + 3 / r r ' + 4 / r r ' r r " … \) where r=s 1 /s 2 , r′ = s 2 /s 3 , etc., N=total striae, p=the reciprocal of the probability of match, s 1 = the number of runs of size 1, etc. When r=r′ = r″… = p, the probability of any striation matching is independent of the other striae. When r′, r″ … are all functions of r, dependent systems are described. When r, r′, r″ … are unrelated, the general case exists, including identical and near-identical striae sets.