A note on a theoretical subsampling distribution of macroplankton

Fiducial limits are obtained for the estimate of numbers of macroplankton in an original sample after subsampling has been undertaken, assuming that successive subsamples follow a binomial distribution. The best estimate of the original number (N) is given by $N^=n¯c·p−k$, wherep is the probability of an organism being in the subsample after one split, k is the number of successive splits and $n¯c$ is the mean of the numbers counted in the final subsample of m(m ≧ 1), such series of independent splits. This method is particularly applicable to results from the Folsom splitter and the recent Burrell subsampler. A worked example is included.