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20182026
most citedFinding -II sibling stars in the Milky Way with the Greedy Optimistic Clustering algorithm

13 citations · 33 across the 25 of their papers we have counts for

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8 papers · 1 filter

stat.ML2025

Algebraic Approach to Ridge-Regularized Mean Squared Error Minimization in Minimal ReLU Neural Network

Ryoya Fukasaku, Yutaro Kabata, Akifumi Okuno

This paper investigates a perceptron, a simple neural network model, with ReLU activation and a ridge-regularized mean squared error (RR-MSE). Our approach leverages the fact that…

stat.ML2021

Improving Nonparametric Classification via Local Radial Regression with an Application to Stock Prediction

Ruixing Cao, Akifumi Okuno, Kei Nakagawa +1

For supervised classification problems, this paper considers estimating the query's label probability through local regression using observed covariates. Well-known nonparametric k…

stat.ML2021

A generalization gap estimation for overparameterized models via the Langevin functional variance

Akifumi Okuno, Keisuke Yano

This paper discusses the estimation of the generalization gap, the difference between generalization performance and training performance, for overparameterized models including ne…

stat.ML2020

Extrapolation Towards Imaginary -Nearest Neighbour and Its Improved Convergence Rate

Akifumi Okuno, Hidetoshi Shimodaira

-nearest neighbour (-NN) is one of the simplest and most widely-used methods for supervised classification, that predicts a query's label by taking weighted ratio of observed…

stat.ML2019★ 5 cited

Robust Graph Embedding with Noisy Link Weights

Akifumi Okuno, Hidetoshi Shimodaira

We propose -graph embedding for robustly learning feature vectors from data vectors and noisy link weights. A newly introduced empirical moment -score reduces the influence o…

stat.ML2018★ 7 cited

Graph Embedding with Shifted Inner Product Similarity and Its Improved Approximation Capability

Akifumi Okuno, Geewook Kim, Hidetoshi Shimodaira

We propose shifted inner-product similarity (SIPS), which is a novel yet very simple extension of the ordinary inner-product similarity (IPS) for neural-network based graph embeddi…

stat.ML2018

On representation power of neural network-based graph embedding and beyond

Akifumi Okuno, Hidetoshi Shimodaira

We consider the representation power of siamese-style similarity functions used in neural network-based graph embedding. The inner product similarity (IPS) with feature vectors com…

stat.ML2018★ 5 cited

A probabilistic framework for multi-view feature learning with many-to-many associations via neural networks

Akifumi Okuno, Tetsuya Hada, Hidetoshi Shimodaira

A simple framework Probabilistic Multi-view Graph Embedding (PMvGE) is proposed for multi-view feature learning with many-to-many associations so that it generalizes various existi…