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Skewness

Skewness is a statistic that is used to measure the symmetry of the distribution for a set of data. The skewness of an analysis domain is calculated as follows:

Skewness = K3 / ESD 3

where:

K3 = [n · Σi (Ei - En)3] / [(n-1)·(n-2)] if n 3;
K3 = 0 if n < 3

summation is over all samples i in the region

n is the number of samples included in the summation.
Ei is the linear Sv of sample i (m2/m3) -  set to 0 for any sample where Ei < mSv or Ei > MSv,
En is the observed Mean Energy of the region in linear units (m2/m3) = 10Sv/10
mSv is the minimum integration threshold (dB re 1 m-1) at time of processing.
MSv is the maximum integration threshold (dB re 1 m-1) at time of processing.
ESD Standard_deviation (Standard Deviation of the Energy)

All symbols are as defined in the nomenclature developed for SHAPES algorithms.

See also

About skewness
School Detection module algorithms
Other region variables for schools analysis