Some consequences of applying lognormal theory to pseudolognormal distributions
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A logarithmic transformation may be used to improve the efficiency of estimates of the mean when observations follow the lognormal distribution. But if this transformation is applied to observations that follow another distribution, bias may be introduced. We consider some consequences of erroneously applying lognormal estimation theory and demonstrate that biased estimates may be obtained for certain classes of distributions. Illustrations of bias obtained in gold sampling are given.
Key wordsdata processing lognormal theory sampling simulation statistics transformations economic geology mining sedimentology
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