arXiv Statistics ML

Multidimensional scaling of two-mode three-way asymmetric dissimilarities: finding archetypal profiles and clustering

The paper extends the h‑plot multidimensional scaling technique to handle three‑way asymmetric dissimilarities, enabling the extraction of archetypal profiles and clustering in a unified Euclidean space. It provides an explicit eigenvector‑based solution that avoids local minima, is scale‑invariant, computationally efficient, and includes a straightforward goodness‑of‑fit assessment. The method is benchmarked against existing models and demonstrated on a financial dataset, with all data and code made publicly available for reproducibility.

arXiv Machine Learning
Oct 9

A Survey on Archetypal Analysis

A Survey on Archetypal Analysis reviews the method introduced by Cutler and Breiman in 1994 for extracting archetypes—distinct aspects—from data, where each observation is expressed as a convex combination of these archetypes. The survey covers AA’s role in feature extraction, dimensionality reduction, and its interpretability, discusses its nonconvex optimization challenges, and surveys applications across various scientific fields. It also outlines best practices, limitations, and future research directions for AA.

By Aleix Alcacer, Irene Epifanio, Sebastian Mair, Morten M{\o}rup
arXiv Machine Learning
Sep 4

Anisotropic View Distance Metric for High-Dimensional Data: Theory, Geometry, and Fast Computation

The paper introduces View distance, a novel metric that projects high‑dimensional data onto all pairwise two‑dimensional planes and sums the Euclidean distances across these projections. It satisfies metric axioms, couples features, suppresses redundancy, and captures anisotropic geometry. To make it scalable, the authors propose a plane‑selection strategy using iterative Maximum Weight Matching, reducing complexity from ω(n²) to ω(k) and demonstrating competitive performance on twelve datasets.

By Yiqun Zhang, Hou-biao Li
arXiv Machine Learning
Aug 27

Efficient Estimation of High Information Projections using Nearest Neighbours

The paper introduces a new dimensionality reduction technique that enhances nearest‑neighbour relationships to estimate high‑information projections. It constructs a matrix encoding local covariance via nearest‑neighbour pairs and shows that, under standard regularity conditions, this matrix consistently estimates the Density Information Matrix (DIM), a non‑parametric analogue of the Fisher Information Matrix. The authors also demonstrate the method’s practical usefulness for clustering and outlier detection.

By David P. Hofmeyr