Dice Question Streamline Icon: https://streamlinehq.com

Generalization of P=2, D=2 MMCR intuition to high-dimensional regimes

Determine the extent to which the closed-form intuition for Maximum Manifold Capacity Representations (MMCR) in the P=2, D=2 case—namely, that maximizing the norm of each mean vector and orthogonalizing the centers maximizes the nuclear norm—extends to general settings with arbitrary numbers of manifolds P and embedding dimensions D in the large-data, high-dimensional regime.

Information Square Streamline Icon: https://streamlinehq.com

Background

MMCR defines a loss as the negative nuclear norm of a matrix of per-datum centers, motivating representations that increase the nuclear norm. For the special case P=2, D=2, a closed-form solution provides intuition: the nuclear norm is maximized when the mean vectors are unit-norm and orthogonal.

The paper notes that, although this low-dimensional case offers intuition, MMCR was theoretically derived and empirically implemented in regimes with large numbers of data and high embedding dimensions. The authors explicitly state uncertainty about how the P=2, D=2 intuition sheds light on general MMCR behavior, motivating their high-dimensional analysis to address this gap.

References

Yerxa et. al (2023) \citep{yerxa2023learning} note that no closed form solution exists for singular values of an arbitrary matrix, but when $P=2, D=2$, a closed form solution exists that offers intuition: $|C|_*$ will be maximized when (i) the norm of each mean is maximized i.e., $|_p|_2 = 1$ (recalling that $0 \leq |_p| < 1$ since the embeddings live on the hypersphere), and (ii) the means $_1, _2$ are orthogonal to one another. While we commend the authors for working to offer intuition, it is unclear to what extent the $P=2, D=2$ setting sheds light on MMCR in general, as MMCR was theoretically derived and numerically implemented in the large data and high dimension regime.

Towards an Improved Understanding and Utilization of Maximum Manifold Capacity Representations (2406.09366 - Schaeffer et al., 13 Jun 2024) in Section 2.2 (Maximum Manifold Capacity Representations)