Conference Proceedings

Characteristics of Local Intrinsic Dimensionality (LID) in Subspaces: Local Neighbourhood Analysis

T Hashem, L Rashidi, J Bailey, L Kulik

Similarity Search and Applications, 12th International Conference, SISAP 2019, Newark, NJ, USA, October 2–4, 2019, Proceedings | Springer | Published : 2019

Abstract

The local intrinsic dimensionality (LID) model enables assessment of the complexity of the local neighbourhood around a specific query object of interest. In this paper, we study variations in the LID of a query, with respect to different subspaces and local neighbourhoods. We illustrate the surprising phenomenon of how the LID of a query can substantially decrease as further features are included in a dataset. We identify the role of two key feature properties in influencing the LID for feature combinations: correlation and dominance. Our investigation provides new insights into the impact of different feature combinations on local regions of the data.