Alexander Erreygers

I am a PhD student at Ghent University, more precisely at the Foundations Lab for Imprecise Probabilities (FLip) of the Department of Electronics and Information Systems, part of the Faculty of Engineering and Architecture. Before October 2017, I was a member of the SMACS Research Group, part of the Department of Telecommunications and Information Processing, for two years. From November 2019 until January 2020, I was on a three month long research stay at the UNIMODE research group of the University of Oviedo, Spain.

Alexander Erreygers My research is focussed around the theory and applications of imprecise probabilities. I first became acquainted with imprecise probabilities during my Master thesis, in which I used imprecise probabilities to model the noise in a one-dimensional discrete-time linear-quadratic optimal control problem. On the theoretical side, I am currently working on stochastic processes, mainly (an imprecise extension of) the Poisson process and (ergodicity of) imprecise continuous-time Markov chains. These stochastic process are used as models in a lot of fields. From a practical point of view, my main interest lies in using these imprecise stochastic processes to robustly model queueing systems.

If interested, you can scroll down to take a look at my scientific output, brief academic CV or contact details.


Scientific output

Journal articles

  1. Alexander Erreygers & Jasper De Bock. Bounding inferences for large-scale continuous-time Markov chains: A new approach based on lumping and imprecise Markov chains. In International Journal of Approximate Reasoning, 115:96–133, Dec. 2019.
  2. Alexander Erreygers, Jasper De Bock, Gert de Cooman & Arthur Van Camp. Optimal control of a linear system subject to partially specified input noise. In International Journal of Robust and Nonlinear Control, 29(12):3892–3914, Aug. 2019.
  3. Alexander Erreygers, Cristina Rottondi, Giacomo Verticale & Jasper De Bock. Imprecise Markov Models for Scalable and Robust Performance Evaluation of Flexi-Grid Spectrum Allocation Policies. In IEEE Transactions on Communications, 66(11):5401–5414, Nov. 2018.

Articles in conference proceedings

  1. Alexander Erreygers & Enrique Miranda. A study of the set of probability measures compatible with comparative judgements. In the proceedings of the 18th International Conference on Information Processing and Management of Uncertainty in Knowledge-Based Systems (IPMU 2020), Jun. 2020.
  2. Alexander Erreygers & Jasper De Bock. First steps towards an imprecise Poisson process. In the proceedings of the 11th International Symposium on Imprecise Probability: Theories and Applications (ISIPTA 2019), Jun. 2019.
  3. Thomas Krak, Alexander Erreygers & Jasper De Bock. An Imprecise Probabilistic Estimator for the Transition Rate Matrix of a Continuous-Time Markov Chain. In the proceedings of the 9th International Conference on Soft Methods in Probability and Statistics (SMPS 2018), Sep. 2018.
  4. Alexander Erreygers & Jasper De Bock. Computing Inferences for Large-Scale Continuous-Time Markov Chains by Combining Lumping with Imprecision. In the proceedings of the 9th International Conference on Soft Methods in Probability and Statistics (SMPS 2018), Sep. 2018.

    Winner of the International Journal of Approximate Reasoning Best Paper Award.

  5. Alexander Erreygers & Jasper De Bock. Imprecise continuous-time Markov chains: Efficient Computational methods with guaranteed error bounds. In the proceedings of the 10th International Symposium on Imprecise Probability: Theories and Applications (ISIPTA'17), Jul. 2017.
  6. Cristina Rottondi, Alexander Erreygers, Giacomo Verticale & Jasper De Bock. Modelling spectrum assignment in a two-service flexi-grid optical link with imprecise continuous-time Markov chains. In the proceedings of the 13th International Conference on the Design of Reliable Communication Networks (DRCN 2017), Mar. 2017.

    Winner of the best paper award.

Posters and presentations

  1. Alexander Erreygers. Imprecise stochastic processes. Invited talk at the University of Oviedo, 11/11/2019.
  2. Alexander Erreygers & Jasper De Bock. Computing limit expectations of imprecise continuous-time Markov chains. Presented at the 11th Workshop on Principles and Methods of Statistical Inference with Interval Probability (WPMSIIP 2018), 1/8/2018.
  3. Alexander Erreygers & Jasper De Bock. Lumping continuous-time Markov chains. Presented at the 10th Workshop on Principles and Methods of Statistical Inference with Interval Probability (WUML/WPMSIIP 2017), 12/9/2017.
  4. Alexander Erreygers & Jasper De Bock. Towards an imprecise Poisson process. Presented at the 10th Workshop on Principles and Methods of Statistical Inference with Interval Probability (WUML/WPMSIIP 2017), 12/9/2017.
  5. Alexander Erreygers & Jasper De Bock. Handling the state space explosion of Markov chains: How lumping introduces imprecision (almost) inevitably. Presented at the 10th International Symposium on Imprecise Probability: Theories and Applications (ISIPTA'17), 14/7/2017.
  6. Cristina Rottondi, Alexander Erreygers, Giacomo Verticale & Jasper De Bock. Modelling spectrum assignment in a two-service flexi-grid optical link with imprecise continuous-time Markov chains. Presented at the 10th International Symposium on Imprecise Probability: Theories and Applications (ISIPTA'17), 10/7/2017.
  7. Alexander Erreygers, Jasper De Bock, Gert de Cooman & Arthur Van Camp. LQ optimal control for partially specified input noise. Presented at the 28th European Conference on Operational Research (EURO2016), 6/7/2016.
  8. Alexander Erreygers, Jasper De Bock, Gert de Cooman & Arthur Van Camp. Optimal control of linear systems with quadratic cost and imprecise forward irrelevant input noise. Presented at the 9th International Symposium on Imprecise Probability: Theories and Applications (ISIPTA'15), 22/7/2015.

Academic CV

Working experience

PhD Student at Ghent University. Oct. 2015 – present

I am currently pursuing my PhD under the supervision of Jasper De Bock, Gert de Cooman and Herwig Bruneel.

Engineering intern at BASF Antwerp. Aug. 2014 – Sep. 2014

During a 4 week internship I built a model of the KPI of a chemical plant using data mining techniques available in the JMP software package.

Teaching

Probability and Statistics 2017-2018 – present

The aim of this course is to teach the student the basic principles and the reasoning methods of probability. Lecturer: Gert de Cooman

Nonlinear Systems 2017-2018 – present

This course discusses the notion of nonlinearity in a dynamical context in a systematic way. In the exercise sessions I supervise, the objective is to get familiar with the tools and techniques useful in the qualitative and quantitative study of the dynamics of nonlinear systems. Lecturer: Jasper De Bock

Queueing Analysis and Simulation 2015-2016 – 2016-2017

This course introduces basic concepts of queueing analysis and simulation for assessing the performance of computer and communication systems. I supervised the exercise sessions on probability theory (and Markov chains in particular), birth-death queues and queueing networks. Lecturers: Joris Walraevens and Dieter Fiems

Academic services

Reviewing

I have reviewed for ISIPTA 2019, Information Fusion and the International Journal of Approximate Reasoning.

ISIPTA 2019

I was a member of the local organising committee of ISIPTA 2019, the 20-year anniversary edition of the International Symposium on Imprecise Probabilities: Theories and Applications. My duties included designing and managing the conference website.

Education

MSc in Electromechanical Engineering at Ghent University. Sep. 2013 – July 2015

Option Control Engineering & Automation, graduated with greatest distinction.

BSc in Electromechanical Engineering at Ghent University. Sep. 2010 – July 2013

Graduated with great distinction.


Contact

Alexander Erreygers
Technologiepark - Zwijnaarde 125
B9052 Zwijnaarde
Belgium
alexander.erreygers@ugent.be