Of ants, bird-photographers on SUVs, epidemic and start-ups!

Note: The page attempts to load a java applet to run a model, so it may take some time depending on your browser and internet connection.

What's the connection with ants, bird-photographers on SUVs, epidemic and start-ups? Well, these were some keywords of the cases that we explored during our first short-course (and perhaps the first one in India!) on Agent-based modeling for studying social and ecological systems". Our foray into modelling complex systems using agent-based models got renewed thrust with this course, which we successfully conducted last weekend. Our participants ranged from leading institutions and think-tanks namely, Indian Institute of Science (IISc), Centre for Study of Science, Technology and Policy (C-STEP) and Ashoka Trust for Research in Ecology and the Environment (ATREE). At the outset, we thank the particpants for enriching interactions and enthusiastic participation that resulted in developing a few agent-based models using NetLogo.


Hands-on with agent-based modelling

Needless to say, the key feature of this course has been its thrust on hands-on exposure to agent-based modelling besides a dedicated session on the theories behind modelling complex systems. The only lecture session attempts to set the thinking and immerse the participants to appreciate complex systems with a lens to understand the 'processes' and 'interactions'.

On day one, particpants were exposed to NetLogo enabling them to understand the concepts, syntax and key aspects of building a custom model. At the end of day one, we had participants taking a stab at building a simple model of ant movements. In this model, ants are created and asked to move around 'green' patches. As the go over them, the 'green' turns 'brown' indicating that they have consumed the food on those patches and move around randomly. We have made the model available here for you to play around. Check it out below:

On day two, we had participants building an agent-based model of their interest of study. Some of the models that were attempted to build are: Studying the Impact of Namma Metro on traffic in Bangalore; Exploring thte impact of bird-photographes on SUVs on grasslands of Hesaraghatta, Studying the effect of population density and recovery time, Studying the effect on anuran population due to landscape fragmentation in Myristica swamps, and Studying the interactions of entrepreneur motivation and skills on start-ups and firm characteristics in Bangalore were some of the cases we explored. Phew! That was quite a bit and all of us had a lot of fun in developing these. We are happy to show-case two of them here. One on Spread of Epidemic and another on the Hesaraghatta Study.

Spread of Epidemic

The model attempts to study the effect of density and recovery time on the spread of epidemic. See the intiial model setup here:

And the model after several runs.

As you can see for the set initial conditions the population stabilises. However, it was found through experiments that increasing the population and hence density can increase number of persons affected suggesting that density plays a key role in the spread of epidemics.
The model output is presented here as a video grab.

The Hesaraghatta Study

For those curious on the Hesaraghatta Study you are requested to visit this site to read the full report here. The lead author of the study participated and developed this model. The model attempts to study the effect on grasslands as a result of bird-photographers chasing birds to shoot on SUVs as against the sheep/cattle and their grazers. See the initial model setup below:


The model after several runs is here:

As you notice the model suggests a greater impact on grasslands from the footprint of SUVs as against the sheep/cattle.
The model output is presented here as a video grab.

Working with agent-based models is fun and is not necessarily complex, but only requires the interest and an open mind. At the end of our course, this is what one of the participant had to say:

The course and the content are good. I am a bit of slow learner especially when it comes to technical things involving computer. I hope that is accepted and allowed to explore things when it comes to building models instead of giving more emphasis on end-product.

We once again sincerely thank all participants and look forward to the next version of the course in August, later this year!