Environmental Assessment
: Data Analysis
:
Univariate
Shannon-Wiener information function, H(s) (Lloyd, Zar and Karr, 1968):
where C = 3.321928 (constant used in converting log10 to log2)
N = the total number of individuals
ni = the number of individuals in the ‘ith’ species
S = the total number of species
Lloyd, H., Zar, J.H., and Karr, J.R. (1968). On the calculation of information - theoretical measures of diversity. Am. Mid Nat. 79, 257-272.
Pielou's evenness index, j (Pielou, 1966):
where H(s) = the Shannon-Wiener information function
H(max.) = the theoretical maximum value for H(s) if all species in the sample were equally abundant.
Pielou, E.C. (1966). The measurement of diversity in different types of biological collections. J. Theor. Biol., 13, 131-144.
Simpson's dominance index, c (Simpson, 1949):
where ni = number of individuals in the ‘ith’ species
N = total number of individuals
S = total number of species
Simpson, E.H. (1949). Measurement of diversity. Nature, Lond. 163, 688.
