Double Logistic Function
The double logistic is a function similar to the logistic function with numerous applications. Its general formula is:
where d is its centre and s is the steepness factor. Here "sgn" represents the sign function.
It is based on the Gaussian curve and graphically it is similar to two identical logistic sigmoids bonded together at the point x = d.
One of its applications is non-linear normalization of a sample, as it has the property of eliminating outliers.
Read more about this topic: Logistic Function
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