Dr. Beniamino Hadj-Amar
I am a Postdoctoral Fellow in the Department of Statistics at Rice University (Houston, TX), working with Marina Vannucci in a collaborative effort with Read Montague's lab at Virginia Tech.
My research area is at the interface between statistics and science, where I am particularly interested in the development of Bayesian methodologies for the automated analysis of complex dynamical time series. I have obtained my Ph.D. in the Oxford-Warwick Statistics Programme (OxWaSP), working under the supervision of Bärbel Finkenstädt (University of Warwick, UK).
Research Interests:
Time Series
Hidden Markov Models
Bayesian Inference
Statistical Spectral Analysis
Bayesian Nonparametrics
Variable Selection
Graphical Models
Gaussian Processes
To identify latent structures, deal with complex streams of temporal data, as well as properly account for model uncertainty, I often need to design highly flexible and interpretable models characterized by non-stationary behavior, non-linear features, and sparse structures. From a methodological perspective, I have experience working on switching models (e.g.hidden Markov and semi-Markov models), change-point models, Gaussian processes, Bayesian nonparametrics, graphical models, Bayesian variable selection, factor models, mixture models, statistical spectral analysis, and Markov chain Monte Carlo. Throughout my academic experience, I have been working on addressing scientific problems in several fields, such as neuroscience (neuromodulation alongside electrophysiological and electrochemical data derived from the conscious human brain, as well as fMRI data), respiratory research (airflow trace data), and circadian studies (datasets obtained from wearable devices).
Publications:
Batten, S.*, Hadj-Amar, B.*, Ahrens, M.L., Oster, M.E., Hartle, A., Barbosa, L.S., Lohrenz, T., White, J.P., Witcher, M.R., Vannucci, M., Montague, R., Howe, M. & Difeliceantonio, A. Task evoked dopamine and norepinephrine track liking in the human amygdala (2024+, submitted)
Hadj-Amar, B., Bornstein, A., Guindani, M., & Vannucci, M., Sparse Gaussian Graphical Modeling of High-Dimensional Time Series with Discrete Autoregressive Processes (2024+, submitted).
Hadj-Amar, B., Jewson, J. & Vannucci, M., Bayesian Sparse Vector Autoregressive Switching Models with Application to Human Gesture Phase Segmentation, Annals of Applied Statistics, 2024, (accepted).
Pluta, D*., Hadj-Amar, B.*, Li, M., Zhao, Y., Versace, F. & Vannucci, M., Improved Data Quality and Statistical Power of Trial-Level Event-Related Potentials with Bayesian Random-Shift Gaussian Processes, Nature Portoflio, Scientific Reports, 2024, 14, 8856.
Bang, D.*, Luo, Y.*, Barbosa, L*., Batten, S*., Hadj-Amar, B.*, Twomey, T., Melville, N., White, J., Torres, A., Celaya, X., Ramaiah, P., McClure, S.M., Brewer, G.A., Bina, R.W., Lohrenz, T., King-Casas, B., Chiu, P., Vannucci, M., Kishida, K., Witcher, M. and Montague, P.R, Noradrenaline tracks emotional modulation of attention in human amygdala. Current Biology, 2023, 33 (22) : 5003-5010.
Hadj-Amar, B., Jewson, J. & Fiecas, M., Bayesian Approximations to Hidden Semi-Markov Models for Telemetric Monitoring of Physical Activity, Bayesian Analysis, 2023, 18 (2) : 547-577.
Sacchi, N., Ciceri, F., Bonifazi, F., Algeri, M., Gallina, A., Pollichieni, S., Raggio, E., Hadj-Amar, B., Lombardini, L., Pupella, S., Liumbruno, G., and Cardillo, M. Availability of HLA-allele-matched unrelated donors and registry size: estimation from haplotype frequency in the Italian population, Journal of Human Immunology, 2021, 82 (10) : 758-766.
Hadj-Amar, B., Finkenstädt, B., Fiecas, M. & Huckstepp, R., Identifying the Recurrence of Sleep Apnea Using a Harmonic Hidden Markov Model, Annals of Applied Statistics, 2021, 15 (3) : 1171-1993.
Hadj-Amar, B., Bayesian Analysis of Nonstationary Periodic Time Series, Ph.D. Thesis, 2020.
Hadj-Amar, B., Finkenstädt, B., Fiecas, M., Levi, F. & Huckstepp, R., Bayesian Model Search for Nonstationary Periodic Time Series, Journal of the American Statistical Association, T&M, 2020, 115 (531) : 1320–1335.
* : joint first author
Software:
AutoNOM: Automatic Nonstationary Oscillatory Modelling, a Julia software to model nonstationary periodic time series.
HHMM: Harmonic Hidden Markov Model, a Julia software to model time-varying periodic and oscillatory processes by means of a Bayesian non-parametric HHMM.
BayesianApproxHSMM: a stan software (and R utilities) to model time series and sequential data using a Bayesian approximation to Hidden semi-Markov models.
mvHMM: contains a suite of software that utilizes multivariate Bayesian hidden Markov models (HMM) for the analysis of signals from monoamine neurotransmitters.
sparseVARHSMM a stan software (and R utilities) to model temporal and contemporaneous (e.g. spatial) dependencies in multivariate time series data using a flexible VAR HSMM.
BayesRPAGP: Bayesian Random Phase-Amplitude Gaussian Process. An R software for Bayesian inference of trial-level analysis of ERP data.