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On the empirical variance of a fractionator estimate
Author(s) -
CruzOrive Luis M.
Publication year - 1990
Publication title -
journal of microscopy
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.569
H-Index - 111
eISSN - 1365-2818
pISSN - 0022-2720
DOI - 10.1111/j.1365-2818.1990.tb03050.x
Subject(s) - estimator , variance (accounting) , sampling (signal processing) , statistics , mathematics , stage (stratigraphy) , econometrics , computer science , biology , paleontology , accounting , filter (signal processing) , business , computer vision
SUMMARY The fractionator consists of several sampling stages with systematic sampling at each stage; data are collected only at the last stage. Therefore, predicting the error variance of a fractionator estimator is a non‐trivial problem, because the observations are correlated in a complicated, unknown way. Gundersen proposed to split the material sampled at the first stage into two subsets, and to compute the variance of the pooled estimate empirically using the corresponding pair of observations made in these two subsets. The idea is very effective, but the estimator thus proposed needed some corrections. The purpose of this paper is to present an improved estimator of the coefficient of error of a fractionator estimator using Gundersen's design.