Q. Explain Shannon-Wiener index?

This diversity measure is based on information theory of measure of order (or disorder) within a particular system. For our uses, this order could be characterized by the number and/or the number of individuals in each species, within our sample plot. By applying these numbers to the Shannon-Wiener equations we can determine what is referred to as the degree of uncertainty. With this number we can then specify our degree of diversity.

where H' = Information content of sample, Index of species diversity or Degree of Uncertainty, s = Number of species, pi = proportion of total sample belonging to i^th species.