Sample Size Required to Estimate the Arithmetic Mean of a Lognormal
Distribution lognormal
Javier Castañeda,
Adriana Perez & Jacky Gil
Abstract
We present close
formulae to calculate the required sample size to estimate the arithmetic mean
of a lognormal distribution for censored and non-censored data. These formulae
were obtained by adjusting non linear models for the exact sample sizes
estimates reported by Perez (1995). The formulae presented are functions of the
estimated geometric standard deviation, the proportional precision from the
true arithmetic mean and using confidence levels of 90%, 95% and 99%. These new
close formulae correct the underestimation problem in other formulae presented
in the statistical literature.
Key words:
Concentration levels, Censoring, Geometric standard desviation, Hougaard
asymmetry measurement.
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