Working Paper
Demba Ba. Working Paper. “Deeply-sparse signal representations”. arXiv Version
Andrew H. Song, Francisco Flores, and Demba Ba. Submitted. “Spike sorting by convolutional dictionary learning.” Advances in Neural Information Processing 31. arXiv Version
Alexander Lin, Yingzhou Zhang, Jeremy Heng, Stephen A. Allsop, Kay M. Tye, Pierre E. Jacob, and Demba Ba. 2019. “Clustering Time Series with Nonlinear Dynamics: A Bayesian Non-Parametric and Particle-Based Approach.” International Conference on Artificial Intelligence and Statistics (AISTATS) 2019.Abstract

We propose a general statistical framework for clustering multiple time series that exhibit nonlinear dynamics into an a-priori unknown number of sub-groups. Our motivation comes from neuroscience, where an important problem is to identify, within a large assembly of neurons, subsets that respond similarly to a stimulus or contingency. Upon modeling the multiple time series as the output of a Dirichlet process mixture of nonlinear state-space models, we derive a Metropolis-within-Gibbs algorithm for full Bayesian inference that alternates between sampling cluster assignments and sampling parameter values that form the basis of the clustering. The Metropolis step employs recent innovations in particle-based methods. We apply the framework to clustering time series acquired from the prefrontal cortex of mice in an experiment designed to characterize the neural underpinnings of fear.

Noa Malem-Shiniski, Yingzhuo Zhang, Daniel T. Gray, Sarah N. Burke, Anne C. Smith, Carol A. Barnes, and Demba. Ba. 9/1/2018. “A separable two-dimensional random field model of binary response data from multi-day behavioral experiments.” Journal of Neursocience Methods, 307, Pp. 175-187. Publisher's Version
Bahareh Tolooshams, Sourav Dey, and Demba Ba. 9/2018. “Scalable convolutional dictionary learning with constrained recurrent sparse auto-encoders.” 2018 IEEE 28th International Worskhop on Machine Learning and Signal Processing. Aalborg, Denmark: IEEE. arXiv Version
Yinghzuo Zhang, Noa Malem-Shinitski, Stephen A. Allsop, Kay Tye, and Demba Ba. 4/2018. “Estimating a separably-Markov random field (SMuRF) from binary observations.” Neural Computation, 30, 4, Pp. 1046-1079. Publisher's Version yingzhuo_zhang.pdf
Stephen A Allsop, Romy Wichmann, Fergil Mills, Anthony Burgos-Robles, Chia-Jung Chang, Ada C. Felix-Ortiz, Alienor Vienne, Anna Beyeler, Ehsan M. Izadmehr, Gordon Glober, Meghan I. Cum, Johanna Stergiadou, Kavitha K. Anandalingham, Kathryn Farris, Praneeth Namburi, Christopher A. Leppla, Javier C. Weddington, Edward H. Nieh, Anne C. Smith, Demba Ba, Emery N. Brown, and Kay M. Tye. 3/3/2018. “Corticoamygdala transfer of socially derived information gates observational learning.” Cell, 173, 6, Pp. 1329-1342. Publisher's Version
Gabriel Schamberg, Demba Ba, and Todd P Coleman. 2/15/2018. “A modularized efficient framework for non-Markov time-series estimation.” IEEE Transactions on Signal Processing, 66, 12. Publisher's Version
Seong-Eun Kim, Michael Behr, Demba Ba, and Emery N. Brown. 1/2/2018. “State-space multitaper time-frequency analysis.” Proceedings of the National Academy of Sciences, 115, 1. Publisher's Version
Noa Shinitski, Yingzhuo Zhang, Daniel T Gray, Sarah N Burke, Anne C Smith, Carol A Barnes, and Demba Ba. 2017. “Can you teach an old monkey a new trick?” Cosyne 2017. shinitski_cosyne_2017.pdf
Yingzhuo Zhang, Noa Shinitski, Stephen Allsop, Kay Tye, and Demba Ba. 2017. “A Two-Dimensional Seperable Random Field Model of Within and Cross-Trial Neural Spiking Dynamics.” Cosyne 2017. zhang_cosyne_2017.pdf
Gabriel Schamberg, Demba Ba, Mark Wagner, and Todd Coleman. 2016. “Efficient low-rank spectrotemporal decomposition using ADMM.” In Statistical Signal Processing Workshop (SSP), 2016 IEEE, Pp. 1–5. IEEE.
Jonathan D Kenny, Jessica J Chemali, Joseph F Cotten, Christa J Van Dort, Seong-Eun Kim, Demba Ba, Norman E Taylor, Emery N Brown, and Ken Solt. 2016. “Physostigmine and Methylphenidate Induce Distinct Arousal States During Isoflurane General Anesthesia in Rats.” Anesthesia and analgesia.
Gabriela Czanner, Sridevi V Sarma, Demba Ba, Uri T Eden, Wei Wu, Emad Eskandar, Hubert H Lim, Simona Temereanca, Wendy A Suzuki, and Emery N Brown. 2015. “Measuring the signal-to-noise ratio of a neuron.” Proceedings of the National Academy of Sciences, 112, 23, Pp. 7141–7146.
Emery Neal Brown, Demba Ba, and Anne Caroline Smith. 2015. “System And Method For Real-Time Analysis And Guidance Of Learning”.
Demba Ba, Simona Temereanca, and Emery N Brown. 2014. “Algorithms for the analysis of ensemble neural spiking activity using simultaneous-event multivariate point-process models.” Frontiers in computational neuroscience, 8, Pp. 6.
EN Brown, D Ba, and S Temereanca. 2014. “Algorithms for the Analysis of Ensemble Neural Spiking Activity Using Simultaneous-Event Multivariate Point-Process Models.” Name: Frontiers in Computational Neuroscience, 8, 6.
Demba Ba, Behtash Babadi, Patrick L Purdon, and Emery N Brown. 2014. “Convergence and stability of iteratively re-weighted least squares algorithms.” IEEE Transactions on Signal Processing, 62, 1, Pp. 183–195.
Luca Citi, Demba Ba, Emery N Brown, and Riccardo Barbieri. 2014. “Likelihood methods for point processes with refractoriness.” Neural computation, 26, 2, Pp. 237–263.
Demba Ba, Behtash Babadi, Patrick L Purdon, and Emery N Brown. 2014. “Neural spike train denoising by point process re-weighted iterative smoothing.” In 2014 48th Asilomar Conference on Signals, Systems and Computers, Pp. 763–768. IEEE.