Calculates estimates of the Shannon-Wiener from count data.
estShannon(x, Nspec = NULL)a integer(numeric) vector of species counts
a single integer value, fixing the number of species to a certain value
A list, containing the elements:
a single numeric value, the estimate with bias correction according to Fritsch and Hsu (1999)
a single numeric value, the raw estimate
a single numeric value, the variance estimate according to Fritsch and Hsu (1999)
Fritsch, KS, and Hsu, JC (1999): Multiple Comparison of Entropies with Application to Dinosaur Biodiversity. Biometrics 55, 1300-1305.
estSimpsonf for estimating Shannon indices pooled over several samples, grouped by a factor