Current position

Education

Research interests

Bayesian Modeling - Computational Statistics - Markov chain Monte Carlo Methods - Functional Data Analysis - Infectious Disease Modeling - Penalized Spline Regression.

Publications in refereed journals

2025

13. Sumalinab, B., Gressani, O., Hens, N. and Faes, C. (2025). A low-rank Bayesian approach for geoadditive modeling.
Spatial Statistics, 68, 100907. doi.org/10.1016/j.spasta.2025.100907

12. Gressani, O., Torneri, A., Hens, N. and Faes, C. (2025). Flexible Bayesian estimation of incubation times.
American Journal of Epidemiology, 194(2):490-501. doi.org/10.1093/aje/kwae192

11. Carmona-Bayonas, A., Álvarez-Escolá, C., Navarro, I.B., [et al., including Gressani, O.]. (2025). Does adjuvant mitotane impact cure rates in adrenocortical carcinoma? Insights From the ICARO-GETTHI/SEEN registry.
The Journal of Clinical Endocrinology & Metabolism. 10.1210/clinem/dgaf082

2024

10. Moreels, N., Boven, A., Gressani, O., Andersson, F.L., Vlieghe, E., Callens, S., Engstrand, L., Simin, J. and Brusselaers, N. (2024). The combined effect of systemic antibiotics and proton pump inhibitors on Clostridioides difficile infection and recurrence. Journal of Antimicrobial Chemotherapy, 79(3):608-616. doi.org/10.1093/jac/dkae012

9. Sumalinab, B., Gressani, O., Hens, N. and Faes, C. (2024). An efficient approach to nowcasting the time-varying reproduction number. Epidemiology, 35(4):512-516. 10.1097/EDE.0000000000001744

8. Sumalinab, B., Gressani, O., Hens, N. and Faes, C. (2024). Bayesian nowcasting with Laplacian-P-splines.
Journal of Computational and Graphical Statistics, 34(2):718–728. 10.1080/10618600.2024.2395414

2023

7. Gressani, O., Faes, C. and Hens, N. (2023). An approximate Bayesian approach for estimation of the instantaneous reproduction number under misreported epidemic data. Biometrical Journal, 65(6):2200024.
doi.org/10.1002/bimj.202200024

6. Vandendijck, Y., Gressani, O., Faes, C., Camarda, C.G. and Hens, N. (2023). Cohort-based smoothing methods for age-specific contact rates. Biostatistics, 25(2):521-540. doi.org/10.1093/biostatistics/kxad005

5. Lambert, P. and Gressani, O. (2023). Penalty parameter selection and asymmetry corrections to Laplace approximations in Bayesian P-splines models. Statistical Modelling, 23(5-6):409-423. doi.org/10.1177/1471082X231181173

2022

4. Gressani, O., Faes, C. and Hens, N. (2022). Laplacian-P-splines for Bayesian inference in the mixture cure model.
Statistics in Medicine, 41(14):2602-2626. doi.org/10.1002/sim.9373

3. Gressani, O., Wallinga, J., Althaus, C., Hens, N. and Faes, C. (2022). EpiLPS: A fast and flexible Bayesian tool for estimation of the time-varying reproduction number.
PLoS Computational Biology, 18(10):e1010618. doi.org/10.1371/journal.pcbi.1010618

2021-2018

2. Gressani, O. and Lambert, P. (2021). Laplace approximations for fast Bayesian inference in generalized additive models based on P-splines. Computational Statistics and Data Analysis, 154:107088. doi.org/10.1016/j.csda.2020.107088

1. Gressani, O. and Lambert, P. (2018). Fast Bayesian inference using Laplace approximations in a flexible promotion time cure model based on P-splines. Computational Statistics and Data Analysis, 124:151-167. doi.org/10.1016/j.csda.2018.02.007

Preprints

6. Rutten, S., Sumalinab, B., Gressani, O., Neyens, T., Duarte, E., Hens, N. and Faes, C. (2025). Distributed lag non-linear models with Laplacian-P-splines for analysis of spatially structured time series.
ArXiv preprint. https://doi.org/10.48550/arXiv.2506.04814

5. Kremer, C., Nundu, S., Vakaniaki, E., [et al., including Gressani, O.]. (2025). Epidemiological characteristics of Mpox virus Clade Ib in the Democratic Republic of the Congo: the impact of transmission mode.
MedRxiv preprint. https://doi.org/10.1101/2025.05.27.25328406

4. Ward, J., Gressani, O., Kim, S., Hens, N. and Edmunds, W.J. (2025). The epidemiology of pathogens with pandemic potential: A review of key parameters and clustering analysis.
MedRxiv preprint. https://doi.org/10.1101/2025.03.13.25323659

3. Gressani, O. and Eilers, P.H.C. (2024). Griddy-Gibbs sampling for Bayesian P-splines models with Poisson data.
ArXiv preprint. https://arxiv.org/abs/2406.03336

2. Gressani, O. and Hens, N. (2024). Nonparametric serial interval estimation.
MedRxiv preprint. https://doi.org/10.1101/2024.10.16.24315600

1. Ward, J., Lambert, J.W., Russell, T.W., Azam, J.M., Kucharski, A.J., Funk, S., Quilty, B.J., Gressani, O., Hens, N. and Edmunds, W.J. (2024). Estimates of epidemiological parameters for H5N1 influenza in humans: a rapid review.
MedRxiv preprint. https://doi.org/10.1101/2024.12.11.24318702

Software packages

4. Gressani, O. (2025). EpiDelays: A software for estimation of epidemiological delays.
https://github.com/oswaldogressani/EpiDelays

3. Gressani, O. (2021). A package for approximate Bayesian inference in mixture cure models with Laplacian-P-splines. https://github.com/oswaldogressani/mixcurelps

2. Gressani, O. (2021). EpiLPS: A fast and flexible Bayesian tool for estimating epidemiological parameters. CRAN.
https://cran.r-project.org/package=EpiLPS

1. Gressani, O. and Lambert, P. (2020). The blapsr package for fast inference in latent Gaussian models by combining Laplace approximations and P-splines. CRAN.
https://cran.r-project.org/package=blapsr

Poster presentations

2. International Society for Bayesian Analysis (ISBA) World Meeting, Edinburgh (UK), 24-29 June 2018: 'Merging Markov chain Monte Carlo with Laplace approximations for fast inference in Generalized additive models'.

1. Survival Analysis for Junior Researchers (SAfJR) conference, Leiden (The Netherlands), 24-26 April 2018: 'P-splines and Laplace approximations for fast Bayesian inference in a flexible promotion time cure model'.

Contributed presentations

9. 30th Annual Meeting of the Royal Statistical Society of Belgium (RSSB), Louvain-la-Neuve (Belgium), 19-20 October 2023: 'Flexible Bayesian estimation of incubation times'.

8. International Conference on Computational and Financial Econometrics (CFE) & Computational and Methodological Statistics (CMStatistics), King's College London (UK), 17-19 December 2022: 'Approximate Bayesian inference in epidemic models: A focus on nowcasting and the time-varying reproduction number'.

7. 36th International Workshop on Statistical Modelling (IWSM), Trieste (Italy), 18-22 July 2022: 'The power of Laplacian-P-splines for inference in epidemiological and survival models'.

6. 28th Annual Meeting of the Royal Statistical Society of Belgium (RSSB), Liège (Belgium), 21-22 October 2021: 'The EpiLPS project: a new Bayesian tool for estimating the time-varying reproduction number'.

5. 42nd Annual Conference of the International Society for Clinical Biostatistics (ISCB), Lyon (France), 18-22 July 2021: 'Laplace approximations for fast Bayesian inference of the time-varying reproduction number under misreported epidemic data'.

4. 40th Annual Conference of the International Society for Clinical Biostatistics (ISCB), Leuven (Belgium), 14-18 July 2019: 'Unifying Laplace’s method and Bayesian penalized regression splines for estimation in generalized additive models'.

3. 26th Annual Meeting of the Royal Statistical Society of Belgium (RSSB), Ovifat (Belgium), 17-19 October 2018: 'Bridging the gap between Bayesian P-splines and Laplace’s method for inference in Generalized additive models'.

2. 37th Annual Conference of the International Society for Clinical Biostatistics; Birmingham (UK), 21-25 August 2016: 'Approximate Bayesian methods in cure survival models: Coupling P-splines with Laplace approximations for fast inference'.

1. 16th Annual Conference of Public Economic Theory, Luxembourg, 02-04 July 2015: 'Endogeneous Quantal Response Equilibrium in Normal Form Games'.

Invited presentations

8. Epinowcast monthly Seminar (online), 5 March 2025: 'The EpiLPS ecosystem'.

7. The Future of Nowcasting Infectious Diseases Meeting, Bilthoven (The Netherlands), 13-14 February 2025: 'Nowcasting with EpiLPS'.

6. P-splines research meeting, IE University School of Science and Technology, Madrid (Spain), 2-3 December 2024: 'The role of P-splines in EpiLPS accompanied by a discussion on the Griddy-Gibbs sampler for Bayesian P-splines'.

5. International Symposium on Nonparametric Statistics, Braga (Portugal), 25-29 June 2024: 'Statistical modeling of infectious diseases with Laplacian-P-splines'.

4. Computational Bayesian Statistics Seminar (online), Flatiron Institute, New York (USA), 27 October 2023: 'Bayesian inference with Laplacian-P-splines: A methodology for fast and flexible estimation of key epidemiologic parameters'.

3. Online Seminar organized by the Center for Computational and Stochastic mathematics (CEMAT) and the Center for Statistics (CEAUL), University of Lisbon (Portugal), 12 October 2022: 'Approximate inference with Bayesian P-splines in epidemic models'.

2. Data Science Institute (DSI) Seminar, Hasselt University, (Belgium), 22 June 2022: 'The power of Laplacian-P-splines'.

1. Statistics Seminar (online) of the Institut de Mathématiques de Marseille I2M (France), 7 December 2020: 'Laplace-P-splines for approximate Bayesian inference'.

Research visits

3. Postdoctoral visiting fellow at Hong Kong University; Hong Kong, January 6-February 4, 2025.

2. Postdoctoral visiting fellow at Basque Center for Applied Mathematics (BCAM); Bilbao (Spain), 27-30 November 2022.

1. Doctoral visiting fellow at Basque Center for Applied Mathematics (BCAM); Bilbao (Spain), 10-13 December 2017.

Grants and funding

4. Postdoctoral visiting fellow at Hong Kong University (January 6 - February 4, 2025). Honorarium of 20000 HK$ from the School of Public Health, LKS Faculty of Medicine, Hong Kong University (Hong Kong).

3. Research Foundation Flanders (Fonds Wetenschappelijk Onderzoek, FWO). Travel grant for a short research visit abroad (January 6 - February 4, 2025), School of Public Health, Hong Kong University (Hong Kong) ~ 1045€.

2. P-splines research meeting (December 2-3, 2024), IE University School of Science and Technology, Madrid (Spain) ~ 560€.

1. AFR grant from the National Research Fund Luxembourg (2014-2015).

Awards

1. Top of the class in the research Master in Statistics (University of Louvain, 2014-2015).

Teaching

As co-lecturer at Hasselt University (2020-)

As teaching assistant at University of Louvain (2015-2020)

2019/20

2018/19

2017/18

2016/17

2015/16

Supervision

Reviewing activities (alphabetical order)

Advances in Statistical Analysis - Biostatistics – Epidemics - Journal of Applied Statistics - PLOS Computational Biology - Scientific Reports - Statistical Modelling - Statistics in Medicine.

Service to University

2017-2019

2016/17



© Oswaldo Gressani 2021-2025. All rights reserved.