MEMOIR: Multi-class Extreme Classification with Inexact Margin

11/24/2018
by   Anton Belyy, et al.
0

Multi-class classification with a very large number of classes, or extreme classification, is a challenging problem from both statistical and computational perspectives. Most of the classical approaches to multi-class classification, including one-vs-rest or multi-class support vector machines, require the exact estimation of the classifier's margin, at both the training and the prediction steps making them intractable in extreme classification scenarios. In this paper, we study the impact of computing an approximate margin using nearest neighbor (ANN) search structures combined with locality-sensitive hashing (LSH). This approximation allows to dramatically reduce both the training and the prediction time without a significant loss in performance. We theoretically prove that this approximation does not lead to a significant loss of the risk of the model and provide empirical evidence over five publicly available large scale datasets, showing that the proposed approach is highly competitive with respect to state-of-the-art approaches on time, memory and performance measures.

READ FULL TEXT
research
01/23/2017

Aggressive Sampling for Multi-class to Binary Reduction with Applications to Text Classification

We address the problem of multi-class classification in the case where t...
research
06/07/2018

Scalable Multi-Class Bayesian Support Vector Machines for Structured and Unstructured Data

We introduce a new Bayesian multi-class support vector machine by formul...
research
10/09/2018

Extreme Classification in Log Memory

We present Merged-Averaged Classifiers via Hashing (MACH) for K-classifi...
research
09/19/2018

Combinatorial and Structural Results for gamma-Psi-dimensions

One of the main open problems of the theory of margin multi-category pat...
research
10/23/2018

DCSVM: Fast Multi-class Classification using Support Vector Machines

We present DCSVM, an efficient algorithm for multi-class classification ...
research
08/17/2010

A unifying view for performance measures in multi-class prediction

In the last few years, many different performance measures have been int...

Please sign up or login with your details

Forgot password? Click here to reset