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Related papers: Optimal weighted nearest neighbour classifiers

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We consider the problem of adaptation to the margin in binary classification. We suggest a penalized empirical risk minimization classifier that adaptively attains, up to a logarithmic factor, fast optimal rates of convergence for the…

Statistics Theory · Mathematics 2007-06-13 A. B. Tsybakov , S. A. van de Geer

The experimental design problem concerns the selection of k points from a potentially large design pool of p-dimensional vectors, so as to maximize the statistical efficiency regressed on the selected k design points. Statistical efficiency…

Machine Learning · Statistics 2017-11-15 Zeyuan Allen-Zhu , Yuanzhi Li , Aarti Singh , Yining Wang

In this paper, we study gap-dependent regret guarantees for risk-sensitive reinforcement learning based on the entropic risk measure. We propose a novel definition of sub-optimality gaps, which we call cascaded gaps, and we discuss their…

Machine Learning · Computer Science 2022-03-08 Yingjie Fei , Ruitu Xu

Expected values weighted by the inverse of a multivariate density or, equivalently, Lebesgue integrals of regression functions with multivariate regressors occur in various areas of applications, including estimating average treatment…

Statistics Theory · Mathematics 2025-02-17 Hajo Holzmann , Alexander Meister

A non-parametric k-nearest neighbour based entropy estimator is proposed. It improves on the classical Kozachenko-Leonenko estimator by considering non-uniform probability densities in the region of k-nearest neighbours around each sample…

Information Theory · Computer Science 2016-01-27 Damiano Lombardi , Sanjay Pant

Nearest Neighbors Algorithm is a Lazy Learning Algorithm, in which the algorithm tries to approximate the predictions with the help of similar existing vectors in the training dataset. The predictions made by the K-Nearest Neighbors…

Machine Learning · Computer Science 2018-11-14 Chandrasekaran Anirudh Bhardwaj , Megha Mishra , Kalyani Desikan

We consider the problem of repeatedly choosing policies to maximize social welfare. Welfare is a weighted sum of private utility and public revenue. Earlier outcomes inform later policies. Utility is not observed, but indirectly inferred.…

Econometrics · Economics 2024-07-30 Nicolo Cesa-Bianchi , Roberto Colomboni , Maximilian Kasy

We study a generalization of the knapsack problem with geometric and vector constraints. The input is a set of rectangular items, each with an associated profit and $d$ nonnegative weights ($d$-dimensional vector), and a square knapsack.…

Data Structures and Algorithms · Computer Science 2021-02-12 Arindam Khan , Eklavya Sharma , K. V. N. Sreenivas

We address the problem of the achievable regret rates with online logistic regression. We derive lower bounds with logarithmic regret under $L_1$, $L_2$, and $L_\infty$ constraints on the parameter values. The bounds are dominated by $d/2…

Machine Learning · Computer Science 2020-02-20 Gil I. Shamir

Forward gradient descent (FGD) has been proposed as a biologically more plausible alternative of gradient descent as it can be computed without backward pass. Considering the linear model with $d$ parameters, previous work has found that…

Statistics Theory · Mathematics 2024-11-27 Niklas Dexheimer , Johannes Schmidt-Hieber

Nearest neighbors (NN) are traditionally used to compute final decisions, e.g., in Support Vector Machines or k-NN classifiers, and to provide users with explanations for the model's decision. In this paper, we show a novel utility of…

Computer Vision and Pattern Recognition · Computer Science 2024-08-28 Giang , Nguyen , Valerie Chen , Mohammad Reza Taesiri , Anh Totti Nguyen

This work is concerned with the estimation of multidimensional regression and the asymptotic behaviour of the test involved in selecting models. The main problem with such models is that we need to know the covariance matrix of the noise to…

Statistics Theory · Mathematics 2008-02-20 Joseph Rynkiewicz

In clinical trials and other applications, we often see regions of the feature space that appear to exhibit interesting behaviour, but it is unclear whether these observed phenomena are reflected at the population level. Focusing on a…

Statistics Theory · Mathematics 2023-09-21 Henry W. J. Reeve , Timothy I. Cannings , Richard J. Samworth

We revisit online binary classification by shifting the focus from competing with the best-in-class binary loss to competing against relaxed benchmarks that capture smoothed notions of optimality. Instead of measuring regret relative to the…

Machine Learning · Statistics 2025-04-16 Omar Montasser , Abhishek Shetty , Nikita Zhivotovskiy

We investigate the classification performance of K-nearest neighbors (K-NN) and deep neural networks (DNNs) in the presence of label noise. We first show empirically that a DNN's prediction for a given test example depends on the labels of…

Machine Learning · Computer Science 2020-12-04 Amnon Drory , Oria Ratzon , Shai Avidan , Raja Giryes

We study the scaling of classification error rates with respect to the size of the training dataset. In contrast to classical results where rates are minimax optimal for a problem class, this work starts with the empirical observation that,…

Machine Learning · Statistics 2025-06-04 Pengkun Yang , Jingzhao Zhang

The estimation of optimal treatment regimes is of considerable interest to precision medicine. In this work, we propose a causal $k$-nearest neighbor method to estimate the optimal treatment regime. The method roots in the framework of…

Machine Learning · Statistics 2017-11-23 Xin Zhou , Michael R. Kosorok

We present the first comprehensive and large-scale evaluation of classical (NN), fuzzy (FNN) and fuzzy rough (FRNN) nearest neighbour classification. We standardise existing proposals for nearest neighbour weighting with kernel functions,…

Machine Learning · Computer Science 2025-06-06 Oliver Urs Lenz , Henri Bollaert , Chris Cornelis

In model selection, several types of cross-validation are commonly used and many variants have been introduced. While consistency of some of these methods has been proven, their rate of convergence to the oracle is generally still unknown.…

Statistics Theory · Mathematics 2021-06-21 Guillaume Maillard

If $(\omega(e))$ is a family of random variables (weights) assigned to the edges of $\mathbb{Z}^d$, the nearest neighbor graph is the directed graph induced by all edges $\langle x,y \rangle$ such that $\omega(\{x,y\})$ is minimal among all…

Probability · Mathematics 2020-07-01 Bounghun Bock , Michael Damron , Jack Hanson