Asymptotically Unbiased Estimator of the Informational Energy with kNN

  • Angel Caţaron Electronics and Computers Department Transylvania University of Braşov, Romania
  • Răzvan Andonie Computer Science Department Central Washington University, Ellensburg, USA
  • Yvonne Chueh Department of Mathematics Central Washington University, Ellensburg, USA


Motivated by machine learning applications (e.g., classification, function approximation, feature extraction), in previous work, we have introduced a nonparametric estimator of Onicescu’s informational energy. Our method was based on the k-th nearest neighbor distances between the n sample points, where k is a fixed positive integer. In the present contribution, we discuss mathematical properties of this estimator. We show that our estimator is asymptotically unbiased and consistent. We provide further experimental results which illustrate the convergence of the estimator for standard distributions.


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How to Cite
CAŢARON, Angel; ANDONIE, Răzvan; CHUEH, Yvonne. Asymptotically Unbiased Estimator of the Informational Energy with kNN. INTERNATIONAL JOURNAL OF COMPUTERS COMMUNICATIONS & CONTROL, [S.l.], v. 8, n. 5, p. 689-698, sep. 2013. ISSN 1841-9844. Available at: <>. Date accessed: 09 aug. 2020. doi:


machine learning, statistical inference, asymptotically unbiased estimator, k-th nearest neighbor, informational energy