Estimation of the Mixing Index Based on the Contact Number between Different Particles by Spot Sampling

The contact number between different particles, C, was previously proposed in contrast to the traditional one proposed by Akao et. al. The former had better properties than the latter in view of sampling efficiency and an evaluation of a mixture.This paper reports on the estimation of C by spot sampling from which the mixing index can be also estimated. The precision of the estimation can be theoretically derived. Comparisons of the estimation precision of C with that of Lacey indicate that the mixing index based on C is superior to Lacey's variance-based mixing index.