Description Usage Arguments Details Value Functions References
Compute the spatial and aspatial Shannon index for a given multitype point pattern.
1 2 3 |
X |
Multitype point pattern of class |
r |
Vector of sizes for neighbourhoods, e.g. |
v2 |
If TRUE, use the real number of types in neighbourhoods as the log-base instead of total population type count. |
... |
Further parametes for the function |
spatial |
If FALSE, return the classical aspatial index value. |
The form of Shannon index is H = 1 - E(o)/E(N), where E(N) is the global entropy and E(o) is the local entropy calculated as E(o)= - sum pi_tau log(pi_tau), where the sum is over the different types present in the pattern, and pi_tau is the expected frequency of type tau points in a neighbourhood of a typical point of the pattern.
The function shannonF
is the calculation function. Uses function segregationFun
.
The function shannon.index
is a shortcut to get the non-spatial Shannon index.
Returns an fv
-object, see spatstat
for more information. The index returns a scalar.
shannon.index
: Traditional index.
Rajala, Illian: A family of spatial biodiversity measures based on graphs, Env. Ecol. Stat. 2012
Reardon, O'sullivan: Measures of spatial segregation. Sociological methodology, 34:121-162, 2004.
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