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Estimating species numbers by extrapolation. II, Estimating the adequate sample size

Ulrich W.

Polish Journal of Ecology

1999

Vol. 47, no 3

293-305

On the basis of large model assemblages estimators are developed to predict the sample size necessary to sample a given fraction of the total species number. The classical method that takes the point of leveling off of the species accumulation curves proved to be less efficient than the use of the second order jackknife in determining the sample size necessary to collect exactly half of the species number (N[O.5]). The present paper studies eight newly developed estimators for N[O.5] and shows that estimators based on a Michaelis-Menten formula and a negative exponential model give even better results with minimal sampling effort. The quality of all estimators was not correlated with simple measures of community structure.