Johan Pensar

Associate Professor - Statistics and Data Science
Image of Johan Pensar
Norwegian version of this page
Room NHA 814
Username
Visiting address Moltke Moes vei 35 Niels Henrik Abels hus 0851 Oslo
Postal address Postboks 1053 Blindern 0316 Oslo
Other affiliations Institutt for pedagogikk (Student)

Academic interests

At a general level, my research interests are focused around the development of statistical and machine learning methods. Some key topics are:

  • Statistical machine learning

  • Probabilistic graphical models

  • Causal learning

  • Statistical genomics

Background

I completed my PhD in statistics in 2016 at Åbo Akademi University (Finland), in which I developed a new class of probabilistic graphical models, along with algorithms for learning the structure of the models from data. During 2016-2020, I worked as a postdoc at University of Helsinki (Finland), developing and applying data analysis tools, primarily for applications in bacterial statistical genomics. Since February 2020, I have been working at UiO as an Associate Professor in Statistics and Data Science. 

Teaching

Supervision (PhD students)

Main supervisor:

  • Anders Hjort (Department of Mathematics, Eiendomsverdi AS, 2020-): Uncertainty in house price prediction (Industrial PhD)
  • Vera Kvisgaard (Department of Mathematics, 2021-): Bayesian estimation of causal effects using directed graphical models
  • Johan de Aguas (Department of Mathematics, Norwegian Institute of Public Health, 2022-): A Bayesian model-averaging toolkit for causal inference with observational data under nonlinear structural equations: An application to the effect of ADHD treatment on school performance by Norwegian children

Co-supervisor:

  • Juri Kuronen (Department of Biostatistics, 2018-): High-dimensional structure learning of Markov networks with applications in bacterial statistical genomics
  • Ghadi Al Hajj (Department of Informatics, 2020-): Improving generalization of machine learning models in medical image and immune receptor sequence analysis through the incorporation of domain priors and constraints
  • Claudio Meggio (Department of Mathematics, CompSci, 2021-): Statistical learning methods for chemistry applications

An overview of available Master's thesis projects can be found here.

Awards

Finnish Statistical Society - Doctoral Thesis Award (2013-2016).

Publications

For a complete list, see my profile at Google Scholar.

 

Tags: Statistics, data science, Probabilistic Graphical Models, Machine Learning

Publications

  • Pavlović, Milena; al Hajj, Ghadi; Kanduri, Chakravarthi; Pensar, Johan; Wood, Mollie Elizabeth & Sollid, Ludvig Magne [Show all 8 contributors for this article] (2024). Improving generalization of machine learning-identified biomarkers using causal modelling with examples from immune receptor diagnostics. Nature Machine Intelligence. 6(1), p. 15–24. doi: 10.1038/s42256-023-00781-8.
  • Hjort, Anders Dahl; Scheel, Ida; Sommervoll, Dag Einar & Pensar, Johan (2023). Locally interpretable tree boosting: An application to house price prediction. Decision Support Systems. ISSN 0167-9236. 178. doi: 10.1016/j.dss.2023.114106. Full text in Research Archive
  • al Hajj, Ghadi; Pensar, Johan & Sandve, Geir Kjetil Ferkingstad (2023). DagSim: Combining DAG-based model structure with unconstrained data types and relations for flexible, transparent, and modularized data simulation. PLOS ONE. ISSN 1932-6203. 18(4). doi: 10.1371/journal.pone.0284443. Full text in Research Archive
  • Corander, Jukka; Hanage, William P & Pensar, Johan (2022). Causal discovery for the microbiome. Lancet Microbe. ISSN 2666-5247. 3(11), p. e881–e887. doi: 10.1016/S2666-5247(22)00186-0. Full text in Research Archive
  • Hjort, Anders Dahl; Pensar, Johan; Scheel, Ida & Sommervoll, Dag Einar (2022). House price prediction with gradient boosted trees under different loss functions. Journal of Property Research. ISSN 0959-9916. 39(4), p. 333–364. doi: 10.1080/09599916.2022.2070525. Full text in Research Archive
  • Pavlović, Milena; Scheffer, Lonneke; Motwani, Keshav; Kanduri, Chakravarthi; Kompova, Radmila & Vazov, Nikolay Aleksandrov [Show all 41 contributors for this article] (2021). The immuneML ecosystem for machine learning analysis of adaptive immune receptor repertoires. Nature Machine Intelligence. 3(11), p. 936–944. doi: 10.1038/s42256-021-00413-z.
  • Chewapreecha, Claire; Pensar, Johan; Chattagul, Supaksorn; Pesonen, Maiju; Sangphukieo, Apiwat & Boonklang, Phumrapee [Show all 18 contributors for this article] (2021). Co-evolutionary Signals Identify Burkholderia pseudomallei Survival Strategies in a Hostile Environment. Molecular Biology and Evolution (MBE). ISSN 0737-4038. 39(1). doi: 10.1093/molbev/msab306. Full text in Research Archive
  • Suotsalo, Kimmo; Xu, Yingying; Corander, Jukka & Pensar, Johan (2021). High-dimensional structure learning of sparse vector autoregressive models using fractional marginal pseudo-likelihood. Statistics and computing. ISSN 0960-3174. 31(73). doi: 10.1007/s11222-021-10049-z. Full text in Research Archive
  • Mageiros, Leonardos; Meric, Guillaume; Bayliss, Sion; Pensar, Johan; Pascoe, Ben & Mourkas, Evangelos [Show all 19 contributors for this article] (2021). Genome evolution and the emergence of pathogenicity in avian Escherichia coli. Nature Communications. ISSN 2041-1723. 12(1). doi: 10.1038/s41467-021-20988-w. Full text in Research Archive
  • Viinikka, Jussi; Hyttinen, Antti; Pensar, Johan & Koivisto, Mikko (2020). Towards Scalable Bayesian Learning of Causal DAGs. Advances in Neural Information Processing Systems. ISSN 1049-5258.
  • Tadei, Alessandro; Haajanen, Juulia; Pensar, Johan; Santtila, Pekka & Antfolk, Jan (2020). Counteracting deceptive responding in the Finnish Investigative Instrument of Child Sexual Abuse (FICSA). Journal of Sexual Aggression. ISSN 1355-2600. doi: 10.1080/13552600.2020.1846802. Full text in Research Archive
  • Top, Janetta; Arredondo-Alonso, Sergio; Schürch, Anita C.; Puranen, Santeri; Pesonen, Maiju & Pensar, Johan [Show all 8 contributors for this article] (2020). Genomic rearrangements uncovered by genome-wide co-evolution analysis of a major nosocomial pathogen, Enterococcus faecium. Microbial Genomics. ISSN 2057-5858. 6(12), p. 1–8. doi: 10.1099/mgen.0.000488. Full text in Research Archive

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  • Sandve, Geir Kjetil Ferkingstad & Pensar, Johan (2022). Machine Learning and Causality.
  • Mageiros, Leonardos; Meric, Guillaume; Bayliss, Sion; Pensar, Johan; Pascoe, Ben & Mourkas, Evangelos [Show all 19 contributors for this article] (2021). Author Correction: Genome evolution and the emergence of pathogenicity in avian Escherichia coli (Nature Communications, (2021), 12, 1, (765), 10.1038/s41467-021-20988-w). Nature Communications. ISSN 2041-1723. 12(1). doi: 10.1038/s41467-021-22238-5.

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Published Feb. 18, 2020 8:49 AM - Last modified Jan. 26, 2024 3:47 PM