Blog columns:

• Reflection about a geodesic passing through two given points in the Poincar´e and Klein disk models of hyperbolic geometry
• [PDF] The symmetrized Bregman divergence as dual geodesic energy functionals
• The harmonic mean of two independent Cauchy distributions is a Cauchy distribution (R code)
• A note on the natural gradient and its connections with the Riemannian gradient, the mirror descent, and the ordinary gradient
• Natural gradient in machine learning (collaborative blog by Wu Lin, Emtiyaz Khan, Mark Schmidt and me)
• Hilbert's simplex distance: A non-separable information monotone distance
• The Kullback-Leibler divergence between a Poisson distribution and a geometric distribution (from a generic formula for the KLD between two different exponential families)
• Cross-entropy, differential entropy and Kullback-Leibler divergence between Rayleigh distributions (some Java code that checks these formula RayleighCrossEntropy.java )
• Building an Apollonian circle packing (August 2020)
• 3D printing of the elliptope (space of 3x3 correlation matrices)
• Structures cannot be avoided! Ramsey theory on the intersection graphs of line segments
• Adaptive Algorithms: Revisiting Klee's measure problem...
• Thales' theorem in Mahalanobis geometry
• The alpha-representation of the Fisher Information Matrix (FIM)
• A note on kernelizing the smallest enclosing ball for machine learning
• A note on the Hyv¨arinen divergence between densities of an exponential family

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(c) Frank Nielsen, Last updated October 2021.