Asia Mathematika

An International Journal. ISSN: 2457-0834 (online)

Volume 3, Issue 1, April 2019, Pages: 79-90

On Some Properties of the Sigmoid Function

Kwara Nantomah

Department of Mathematics, Faculty of Mathematical Sciences, University for Development Studies, Navrongo Campus, P. O. Box 24, Navrongo, UE/R, Ghana.


By using some analytical techniques, we establish some properties of the sigmoid function. The properties are in the form of inequalities involving the function. Some of these inequalities connect the sigmoid function to the softplus function.


Sigmoid function, logistic function, softplus function, inequality, MN-convex function


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