Conditional Recovery Estimation Through Probability Kriging — Theory and Practice

Abstract

The probability kriging technique is an improvement on the distribution free indicator kriging technique for obtaining conditional recoverable reserves. Probability kriging is similar to indicator kriging in that both techniques utilize indicator data and no assumption concerning the shape of the conditional distribution is made. Indicator kriging however does not utilize some easily obtainable information which causes, in certain cases, the indicator kriging estimator to be smoothed, conditionally biased, and in general a poor local estimator. The cases where indicator kriging performs poorly will be identified and it will be shown that by including additional information, through the probability kriging estimator, that the quality of the estimator will be improved. The probability kriging technique is then tested on a gold deposit and the results are presented.