Landmark Map: An Extension of the Self-Organizing Map for a User-Intended Nonlinear Projection

TL;DR

This paper introduces Landmark Map (LAMA), an extension of the self-organizing map that incorporates landmarks to produce user-directed nonlinear projections for enhanced data visualization and analysis.

Contribution

LAMA extends SOM by integrating landmarks, enabling user-guided nonlinear projections for improved data visualization and interpretation.

Findings

LAMA provides landmark-centered data visualizations.

LAMA successfully maps articular movements to cursor movements.

LAMA offers new perspectives for data mining and HCI applications.

Abstract

The self-organizing map (SOM) is an unsupervised artificial neural network that is widely used in, e.g., data mining and visualization. Supervised and semi-supervised learning methods have been proposed for the SOM. However, their teacher labels do not describe the relationship between the data and the location of nodes. This study proposes a landmark map (LAMA), which is an extension of the SOM that utilizes several landmarks, e.g., pairs of nodes and data points. LAMA is designed to obtain a user-intended nonlinear projection to achieve, e.g., the landmark-oriented data visualization. To reveal the learning properties of LAMA, the Zoo dataset from the UCI Machine Learning Repository and an artificial formant dataset were analyzed. The analysis results of the Zoo dataset indicated that LAMA could provide a new data view such as the landmark-centered data visualization. Furthermore, the artificial formant data analysis revealed that LAMA successfully provided the intended nonlinear projection associating articular movement with vertical and horizontal movement of a computer cursor. Potential applications of LAMA include data mining, recommendation systems, and human-computer interaction.