NEW! Stochastic Hybrid Models of Community Dynamics

Nov 10-12, 2025

Carlos MELIAN

Dr Carlos Melian, University of Bern

Dr Leonardo Aguirre, EAWAG

The workshop revolves around community dynamics of interacting populations in variable environments. We will frame community dynamics as a stochastic hybrid model, combining gradual differential equation dynamics with abrupt stochastic state jumps. Beyond providing some technical background about stochastic hybrid models, the workshop will also explore how combining deterministic and stochastic systems can serve as a bridge between the simplified conceptual models prevalent in theoretical ecology and more detailed descriptions accounting for real-world scenarios. In order to strengthen bottom-up research, participants are encouraged to bring their own model ideas and data. A major focus will then be to formalize them as stochastic hybrid models and thereby providing the starting point for an independent research project.

Before the Workshop

• Participants are contacted by email about their specific interests and pointed to relevant online resources as a first orientation.

Day 1

• Input: Dr. Aguirre will provide some background on mathematical and computational aspects of stochastic hybrid models illustrated with various examples from the literature.
• We will collect potential new model ideas provided by the participants as well as the organizers. Each participant may then decide on one of the models as a personal focus for the rest of the workshop (collaboration of several participants on a common model is possible but not necessary).
• Participants will begin to formalize their focus as a stochastic hybrid model with the support of the organizers.

Day 2

• Catching up: Each participant (group) may provide an update about their focus model, the progress in formalizing the model and issues along the way. These items can then be discussed in plenum to get useful feedback and to identify typical steps in devising stochastic hybrid models.
• Input: Dr. Aguirre will give some input about how to forward-simulate stochastic hybrid models in software. Examples are in Python but the presentation is sufficiently general to be used in the participants' language of choice. Minimal programming experience is useful but not necessary (if you are unsure about this or any other point, you may contact leonardo.aguirre(at)eawag(dot)ch or carlos.melian(at)eawag(dot)ch).
• Participants/groups will work on their focus models and implement them with assistance of the organizers. The EAWAG computing infrastructure will be used to generate the simulation data.

Day 3

• Participants will inspect the simulation outputs and try to get a feel for the model behaviour.
• We will discuss possible avenues for developing the models into a small research project based on the participants' interests. Possible directions could be parameter inference, analysis of the model's stationary distributions etc. The organizers will provide some guidance about how to approach these topics.
• Participants will devise a preliminary project timeline.

For any inquiries, please contact: leonardo.aguirre(at)eawag(dot)ch or carlos.melian(at)eawag(dot)ch.

EAWAG Kastanienbaum

Map

When?
10-12 November 2025

Where?
EAWAG, Seestrasse 79, 6047 Kastanienbaum

Contact:
@: ecologie-evolution(at)cuso(dot)ch

Reimbursements for CUSO EE students:
- Train ticket, 2nd class, half-fare from the central train station of your university to the place of the activity. Please claim the expenses via your myCUSO account. See HERE for the procedure.

Late cancellations or no-show: administrative fee of 100 CHF.

FULL BOARD FEES:

• CUSO PhD Students: FREE
  
• Other CUSO participants (postgraduates, postdocs, etc. from CUSO universities = UNIL, UNIBE, UNINE, UNIFR and UNIGE): 400 CHF
  
• External participants, i.e. from non-CUSO universities: 500 CHF
  

External participants (i.e. from a non-CUSO university): Please contact ecologie-evolution(at)cuso(dot)ch before registering! Thanks.

In case of cancellations before Oct 19, 2025: free
Late cancellations or no-show: administrative fee of 100 CHF

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