**(section: 3 / paragraph: b. / sub-paragraph: iv. / line: 2)**

Students should be familiar with all three. If used for the National competition the national supervisor will specify which is being used. We have chosen to define the Simpson index, p as the proportion (n/N) of individuals of one particular species found (n) divided by the total number of individuals found (N), Σ is still the sum of the calculations, and s is the number of species. This information can be found on the files distributed at coaches clinics and will also be on the SO website once the clinics are over.