%0 Journal Article
%A Williams, T.
%T Interval Estimates for Efficiency of Plating
%D 1968
%J Journal of General Virology,
%V 2
%N 1
%P 13-18
%@ 1465-2099
%R https://doi.org/10.1099/0022-1317-2-1-13
%I Microbiology Society,
%X SUMMARY The observed efficiency of plating (e.o.p.) is defined as the ratio of two plaque or colony counts and is in practice subject to substantial sampling fluctuations. The true e.o.p. is here defined as the ratio of the underlying mean values, of which the two counts are Poissonian estimates: thus, when the number of counts on each plate is assumed to increase indefinitely, the observed e.o.p. converges in probability to the true e.o.p. A contour map is provided, by means of which one may rapidly determine, for any given pair of counts in the range 50 to 1000, an interval which will in 95 % of all cases contain the true e.o.p.
%U https://www.microbiologyresearch.org/content/journal/jgv/10.1099/0022-1317-2-1-13