- Letter
- Open Access
Correlation dimension of natural language in a statistical manifold
Phys. Rev. Research 6, L022028 – Published 2 May, 2024
DOI: https://doi.org/10.1103/PhysRevResearch.6.L022028
Abstract
The correlation dimension of natural language is measured by applying the Grassberger-Procaccia algorithm to high-dimensional sequences produced by a large-scale language model. This method, previously studied only in a Euclidean space, is reformulated in a statistical manifold via the Fisher-Rao distance. Language exhibits a multifractal, with global self-similarity and a universal dimension around 6.5, which is smaller than those of simple discrete random sequences and larger than that of a Barabási-Albert process. Long memory is the key to producing self-similarity. Our method is applicable to any probabilistic model of real-world discrete sequences, and we show an application to music data.
Physics Subject Headings (PhySH)
Article Text
Supplemental Material
References (35)
- P. Grassberger and I. Procaccia, Characterization of strange attractors, Phys. Rev. Lett. 50, 346 (1983).
- A. R. Osborne and A. Provenzale, Finite correlation dimension for stochastic systems with power-law spectra, Physica D 35, 357 (1989).
- L. Lacasa and J. Gómez-Gardenes, Correlation dimension of complex networks, Phys. Rev. Lett. 110, 168703 (2013).
- W. Li, Mutual information functions of natural language texts (Citeseer, 1989)
- E. G. Altmann, G. Cristadoro, and M. D. Esposti, On the origin of long-range correlations in texts, Proc. Natl. Acad. Sci. USA 109, 11582 (2012).
- K. Tanaka-Ishii and A. Bunde, Long-range memory in literary texts: On the universal clustering of the rare words, PLoS ONE 11, e0164658 (2016).
- I. Doxas, S. Dennis, and W. L. Oliver, The dimensionality of discourse, Proc. Natl. Acad. Sci. USA 107, 4866 (2010).
- T. Kobayashi and K. Tanaka-Ishii, Taylor's law for human linguistic sequences, in Proceedings of the 56th Annual Meeting of the Association for Computational Linguistic (2018), p. 1138.
- K. Tanaka-Ishii and T. Kobayashi, Taylor's law for linguistic sequences and random walk models, J. Phys. Commun. 2, 115024 (2018).
- M. Ausloos, Measuring complexity with multifractals in texts. Translation effects, Chaos, Solitons Fractals 45, 1349 (2012).
- A. Radford, J. Wu, R. Child et al., Language models are unsupervised multitask learners, OpenAI blog 1, 9 (2019).
- OpenAI, J. Achiam, S. Adler, S. Agarwal, L. Ahmad, I. Akkaya, F. L. Aleman, D. Almeida, J. Altenschmidt, S. Altman et al., GPT-4 technical report, arXiv:2303.08774.
- H. Touvron, L. Martin, K. Stone, P. Albert, A. Almahairi, Y. Babaei, N. Bashlykov, S. Batra, P. Bhargava, S. Bhosale et al., Llama 2: Open foundation and fine-tuned chat models, arXiv:2307.09288.
- The Yi model, (2024), visited in January 2024, https://huggingface.co/01-ai/Yi-34B.
- C. R. Rao, Information and the accuracy attainable in the estimation of statistical parameters, in Breakthroughs in Statistics: Foundations and Basic Theory (Springer, New York, 1992), pp. 235–247.
- S.-I. Amari, Differential-Geometrical Methods in Statistics, Vol. 28 (Springer, New York, 2012).
- Y. B. Pesin, On rigorous mathematical definitions of correlation dimension and generalized spectrum for dimensions, J. Stat. Phys. 71, 529 (1993).
- D. A. Russell, J. D. Hanson, and E. Ott, Dimension of strange attractors, Phys. Rev. Lett. 45, 1175 (1980).
- See Supplemental Material at http://link.aps.org/supplemental/10.1103/PhysRevResearch.6.L022028 for theoretical analysis of our method and extensive evaluation results.
- E. G. Altmann, J. B. Pierrehumbert, and A. E. Motter, Beyond word frequency: Bursts, lulls, and scaling in the temporal distributions of words, PLoS ONE 4, e7678 (2009).
- H.-O. Peitgen, H. Jürgens, D. Saupe, and M. J. Feigenbaum, Chaos and Fractals: New Frontiers of Science, Vol. 7 (Springer, New York, 1992).
- J. M. Marstrand, Some fundamental geometrical properties of plane sets of fractional dimensions, Proc. London Math. Soc. s3-4, 257 (1954).
- K. Falconer, Fractal Geometry: Mathematical Foundations and Applications (John Wiley & Sons, England, 2004).
- Z. Balogh and A. Iseli, Dimensions of projections of sets on riemannian surfaces of constant curvature, Proc. Am. Math. Soc. 144, 2939 (2016).
- https://www.gutenberg.org/ebooks/996.
- D. M. Blei, A. Y. Ng, and M. I. Jordan, Latent dirichlet allocation, J. Mach. Learn. Res. 3, 993 (2003).
- P. Abry, P. Flandrin, M. S. Taqqu, and D. Veitch, Self-similarity and long-range dependence through the wavelet lens, Theor. Applic. Long-Range Depend. 1, 527 (2003).
- D. Kershaw and R. Koeling, Elsevier OA CC-BY corpus, arXiv:2008.00774.
- https://plato.stanford.edu/.
- J. D. Farmer, Information dimension and the probabilistic structure of chaos, Z. Naturforsch. A 37, 1304 (1982).
- A.-L. Barabási and R. Albert, Emergence of scaling in random networks, Science 286, 509 (1999).
- R. Rak and E. Rak, The fractional preferential attachment scale-free network model, Entropy 22, 509 (2020).
- J. Copet et al., Simple and controllable music generation, in Advances in Neural Information Processing Systems (New Orleans, Louisiana, 2023).
- G. Tzanetakis and P. Cook, Musical genre classification of audio signals, IEEE Trans. Speech Audio Process. 10, 293 (2002).
- N. Chomsky, Aspects of the Theory of Syntax, Vol. 11 (MIT Press, Cambridge, MA, 2014).