核心概念
This paper introduces the fast Möbius transform, a novel method leveraging algebraic properties of the redundancy lattice to efficiently compute information decomposition, enabling previously intractable analyses of synergy, redundancy, and unique information in complex systems with up to five variables.
摘要
The Fast Möbius Transform: Enabling Efficient Computation of Information Decomposition (Research Paper Summary)
Bibliographic Information: Jansma, A., Mediano, P. A. M., & Rosas, F. E. (2024). The Fast Möbius Transform: An algebraic approach to information decomposition. arXiv preprint arXiv:2410.06224v1.
Research Objective: This paper aims to address the computational limitations of Partial Information Decomposition (PID) and Integrated Information Decomposition (ΦID) by introducing a novel, algebraically-grounded method called the fast Möbius transform.
Methodology: The authors leverage the algebraic structure of the redundancy lattice, specifically its properties as a free distributive lattice, to derive a closed-form formula for the Möbius function. This formula enables the direct calculation of information atoms without the need for computationally expensive lattice construction or system of equations inversion.
Key Findings:
- The fast Möbius transform significantly reduces the computational complexity of PID and ΦID, making analyses with up to five variables tractable.
- The authors provide a closed-form expression for calculating the top-most synergy atom directly from lower-order redundancies, further enhancing computational efficiency.
- Two case studies demonstrate the practical utility of the method: (1) decomposing information about brain functional connectivity from EEG frequency bands and (2) analyzing cross-scale information dynamics in the music of Bach and Corelli.
Main Conclusions: The fast Möbius transform offers a powerful new approach to information decomposition, enabling analyses of larger systems and opening avenues for exploring the algebraic foundations of information theory.
Significance: This work significantly advances the field of information decomposition by providing a computationally efficient method for analyzing complex systems, with potential applications in neuroscience, genetics, machine learning, and other domains.
Limitations and Future Research: While the fast Möbius transform enables analyses of systems with up to five variables, computational limitations persist for larger systems. Future research could explore alternative approaches or approximations for tackling higher-order information decomposition problems.
统计
The 5-variable Möbius function could be stored in under 400kB, since only around 0.5% of the possible entries are non-zero.
The Dedekind number for n = 6 is |D6| = 7,828,354, which means that storing the 6-variable Möbius function is likely to take up over 400GB — assuming similar sparsity.
27 information atoms among the five frequency bands of brain activity were significant beyond the 95th percentile of their null distribution.
引用
"In this paper we present a novel approach that exploits the rich algebraic structure of the redundancy lattice, which leads to a method we call the fast Möbius transform."
"Our approach is based on a novel formula for estimating the Möbius function that circumvents important computational bottlenecks."
"Overall, our proposed approach illuminates the value of algebraic facets of information decomposition and opens the way to a wide range of future analyses."