Linear and Fisher Separability of Random Points in the <i>d</i>-Dimensional Spherical Layer and Inside the <i>d</i>-Dimensional Cube

• Main Authors: Sergey Sidorov, Nikolai Zolotykh
• Format: Article
• Language: English
• Published: MDPI AG 2020-11-01
• Series: Entropy
• Subjects: stochastic separation theorems; random points; 1-convex set; linear separability; Fisher separability; Fisher linear discriminant
• Online Access: https://www.mdpi.com/1099-4300/22/11/1281

Stochastic separation theorems play important roles in high-dimensional data analysis and machine learning. It turns out that in high dimensional space, any point of a random set of points can be separated from other points by a hyperplane with high probability, even if the number of points is exponential in terms of dimensions. This and similar facts can be used for constructing correctors for artificial intelligent systems, for determining the intrinsic dimensionality of data and for explaining various natural intelligence phenomena. In this paper, we refine the estimations for the number of points and for the probability in stochastic separation theorems, thereby strengthening some results obtained earlier. We propose the boundaries for linear and Fisher separability, when the points are drawn randomly, independently and uniformly from a <i>d</i>-dimensional spherical layer and from the cube. These results allow us to better outline the applicability limits of the stochastic separation theorems in applications.