skbio.diversity.alpha.
simpson
(counts)[source]¶Calculate Simpson’s index.
State: Experimental as of 0.4.0.
Simpson’s index is defined as 1 - dominance
:
where \(p_i\) is the proportion of the community represented by OTU \(i\).
Parameters: | counts (1-D array_like, int) – Vector of counts. |
---|---|
Returns: | Simpson’s index. |
Return type: | double |
See also
Notes
The implementation here is 1 - dominance
as described in [1]. Other
references (such as [2]) define Simpson’s index as 1 / dominance
.
References
[1] | http://folk.uio.no/ohammer/past/diversity.html |
[2] | http://www.pisces-conservation.com/sdrhelp/index.html |