Spectral learning of Bernoulli linear dynamical systems models

Autor: Stone, Iris R., Sagiv, Yotam, Park, Il Memming, Pillow, Jonathan W.
Rok vydání: 2023
Předmět:
Zdroj: Transactions on Machine Learning Research (2023)
Druh dokumentu: Working Paper
Popis: Latent linear dynamical systems with Bernoulli observations provide a powerful modeling framework for identifying the temporal dynamics underlying binary time series data, which arise in a variety of contexts such as binary decision-making and discrete stochastic processes (e.g., binned neural spike trains). Here we develop a spectral learning method for fast, efficient fitting of probit-Bernoulli latent linear dynamical system (LDS) models. Our approach extends traditional subspace identification methods to the Bernoulli setting via a transformation of the first and second sample moments. This results in a robust, fixed-cost estimator that avoids the hazards of local optima and the long computation time of iterative fitting procedures like the expectation-maximization (EM) algorithm. In regimes where data is limited or assumptions about the statistical structure of the data are not met, we demonstrate that the spectral estimate provides a good initialization for Laplace-EM fitting. Finally, we show that the estimator provides substantial benefits to real world settings by analyzing data from mice performing a sensory decision-making task.
Comment: Published in Transactions on Machine Learning Research (https://jmlr.org/tmlr/papers/)
Databáze: arXiv