Tag Archives: computational modelling

Socio-Environmental Dynamics over the Last 12,000 Years workshop, Kiel, Germany 2-24, March 2017

University of Kiel, Germany will be hosting a workshop “Socio-Environmental Dynamics over the Last 12,000 Years: The Creation of Landscapes IV” between 20-24th March 2017.   It includes several sessions on simulation, modelling and ABM with a special emphasis on socio-natural systems.  The abstract submission deadline is a still quite some time (30th November) but it may be worth putting the event into your calendars if you are not planning on crossing the ocean for the CAA in Atlanta or the SAAs in Vancouver.

For more information see the workshop website: http://www.workshop-gshdl.uni-kiel.de

 

Image source: https://en.wikipedia.org/wiki/Kiel#/media/File:Postcard_Panorama_of_Kiel_(1902).jpg

CFP: Computational Social Science Society of the Americas, Santa Fe, Nov 17-20

The CSSSA will be hosting its annual conference in November, bringing researchers from all stripes of computational social science together in beautiful Santa Fe, New Mexico. According to the website, some of the topics to be discussed at the meeting include (but are not limited to):

  • Social network analysis
  • Agent-based models / modeling
  • Emergence
  • Economic models / resource allocation
  • Population dynamics
  • Ecosystems
  • Political/social systems
  • Biological systems / metabolism / bioenergetics
  • Efficiencies / fitness functions
  • Competition / cooperation
  • Networks / information flow
  • Social contagion
  • Vision / knowledge acquisition
  • Influence
  • Swarm intelligence
  • Adaptation / evolution
  • Decision making
  • Local knowledge / global patterns
  • Game theoretic models
  • Strategy
  • Learning

Applications close August 15th, 2016. For more information, check out the CSSSA website.

Image source: Wikimedia Commons/U.S. Public Domain

CAA in Atlanta: 2017 dates

The Simulating Complexity team is all coming home from a successful conference in Oslo. Highlights include a 2-day workshop on agent-based modeling led by the SimComp team, a roundtable on complexity and simulation approaches in archaeology, and a full-day session on simulation approaches in archaeology.

We are all looking forward to CAA 2017 in Atlanta. Dates were announced at Oslo, so start planning.

CAA2017 will be held at Georgia State University March 13th-18th. This leaves 2 weeks before the SAAs, so we hope to have a good turnout on simulation and complexity approaches at both meetings!

SSI to the rescue

Ever heard of the Software Sustainability Institute? It is an EPSRC (UK’s engineering and physical science research council) funded organisation championing best practices in research software development (they are quite keen on best practice in data management as well). They have some really useful resources such as tutorials, guides to best practice and listings of the software and data carpentry training events. I wanted to draw your attention to them, because I fell that the times when archaeological simulations will need to start conforming to the painful (yet necessary) software development standards are looming upon us. The institute’s website is a great place to start.

More to the point, the Institute has just release a call for projects (see below for details). In a nutshell, the idea is that a team of research software developers (read: MacGyver meets Big-Bang-Theory) comes over and makes your code better, speeds up your simulation (e.g., by parallelising it), improves your data storage strategy, stabilises the simulation, helps with developing unit testing or version control, packs the model into an ‘out-of-the-box’ format (e.g., by developing a user-friendly interface) or whatever else you ask for that will make your code better, more sustainable, more reusable/replicable or useful for a wider community. All of that free of charge.

The open call below mentions BBSCR and ESRC, but projects funded through any UK research council (incl. AHRC and NERC), other funding bodies as well as projects based abroad are eligible to apply. The only condition is that applications “are judged on the positive potential impact on the UK research community”. The application is pretty straight forward and the call comes up twice to three times a year. The next deadline is 29th April. See below for the official call and follow the links for more details.

 

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Get help to improve your research software

If you write code as part of your research, then you can get help to improve it – free of charge – through the Software Sustainability Institute’s Open Call for Projects. The call closes on April 29 2016.

Apply at http://bit.ly/ssi-open-call-projects

You can ask for our help to improve your research software, your development practices, or your community of users and contributors (or all three!). You may want to improve the sustainability or reproducibility of your software, and need an assessment to see what to do next. Perhaps you need guidance or development effort to help improve specific aspects or make better use of infrastructure.

We accept submissions from any discipline, in relation to research software at any level of maturity, and are particularly keen to attract applications from BBSRC and ESRC funding areas.

The Software Sustainability Institute is a national facility funded by the EPSRC. Since 2010, the Institute’s Research Software Group[1] has assisted over 50 projects across all the UK Research Councils. In an ongoing survey, 93% of our previous collaborators indicated they were “very satisfied” with the results of the work. To see how we’ve helped others, you can check out our portfolio of past and current projects[2].

A typical Open Call project runs between one and six months, during which time we work with successful applicants to create and implement a tailored work plan. You can submit an application to the Open Call at any time, which only takes a few minutes, at http://bit.ly/ssi-open-call-projects.

We’re also interested in partnering on proposals. If you would like to know more about the Open Call, or explore options for partnership, please get in touch with us at info (at) software (dot) ac (dot) uk.

Everything you ever wanted to know about building a simulation, but without the jargon

I think everyone who had anything to do with modelling came across an innocent colleague/supervisor/another academic enthusiastically exclaiming:

“Well, isn’t this a great topic for a simulation? Why don’t we put it together – you do the coding and I’ll take care of the rest. It will be done and dusted in two weeks!”

“Sure! I routinely build well-informed and properly tested simulations in less than two weeks.” – answered no one, ever.

Building a simulation can be a long and frustrating process with unwelcome surprises popping out at every corner. Recently I summarised the 9 phases of developing a model and the most common pitfalls in an paper published in Human Biology: ‘So You Think You Can Model? A Guide to Building and Evaluating Archaeological Simulation Models of Dispersals‘. It is an entirely jargon free overview of the simulation pipeline, predominantly aimed at anyone who want to start building their own archaeological simulation but does not know what does the process entail. It will be equally useful to non-modellers, who want to learn more about the technique before they start trusting the results we throw at them. And, I hope, it may inspire more realistic time management for simulation projects 🙂

You can access the preprint of it here. It is not as nicely typeset as the published version but, hey!, it is open access.

 

Tim Kohler–The Nine Questions

photo by Roger Cozien

I sat down with Tim Kohler, the creator of the Village Ecodynamics Project agent-based model, professor of anthropology at Washington State University, researcher at Crow Canyon Archaeological Center, and external faculty at the Santa Fe Institute, to discuss his philosophy on complexity science and archaeology, and get some tips for going forward studying complex systems.

How did you get introduced to complexity science:

I took a sabbatical in the mid-1990s and was fortunate to be able to do it at the Santa Fe Institute. Being there right when Chris Langton was developing Swarm, and just looking over his shoulder while he was developing it, was highly influential; Swarm was the original language that we programmed the Village Ecodynamics Project in. Having the opportunity to interact with scientists of many different types at the Santa Fe Institute (founded in 1984) was a wonderful opportunity. This was not an opportunity available to many archaeologists, so one of the burdens I bear, which is honestly a joyful burden, is that having had that opportunity I need to promulgate that to others who weren’t so lucky. This really was my motive for writing Complex Systems and Archaeology in “Archaeological Theory Today” (second edition).

What complexity tools do you use and how?

I primarily use agent-based modeling, although in Complex Systems and Archaeology  I recognize the values of the many other tools available. But I’d point out that I do an awful lot of work that is traditional archaeology too. I recently submitted an article that attempts to look at household-level inequality from the Dolores Archaeological Project data, and this is traditional archaeological inquiry. I do these studies because I think that they contribute in an important way to understanding whether or not an exercise in a structure like the development of leadership model, gives us a sensible answer. This feeds in to traditional archaeology.

In 2014 I published an article calculating levels of violence in the American Southwest. This is traditional archaeology, although it does use elements of complexity. I can’t think of other instances where archaeologists have tried to analyze trajectories of things through time in a phase-space like I did there. The other thing that I do that is kind of unusual in archaeology (not just complexity archaeology) is that I have spent a lot of time and effort trying to estimate how much production you can get off of landscapes. Those things have not really been an end in themselves, although they could be seen as such. However, I approached trying to estimate the potential production of landscapes so that it could feed into the agent-based models. Thus these exercises contribute to complex systems approaches.

What do you think is the unique contribution that complexity science has for archaeology?

I got interested in complexity approaches in early to mid 1990s; during that time when you look around the theoretical landscape there were two competing approaches on offer in archaeology: 1) Processualism (the new archaeology), and the reaction to processualism, 2) Post-processualism, which came from the post-modern critique.

First, with processualism. There has been a great deal of interesting and useful work done through that framework, but if you look at some of that work it really left things lacking. An article that really influenced my feelings on that approach was Feinman’s, famous article “Too Many Types: An Overview of Sedentary Prestate Societies in the Americas” from Advances in Archaeological Method and Theory (1984). He does a nice analysis in the currency of variables having to do with maximal community size, comparison of administrative levels, leadership functions, etc. I would argue that these variables are always a sort of abstraction on the point of view of the analyst. And people, as they are living their daily lives, are not aware of channeling their actions along specific dimensions that can be extracted along variables; people act, they don’t make variables, they act! It’s only through secondary inference that some outcome of their actions (and in fact those of many others) can be distilled as a ‘variable.’ My main objection to processualism is that everything is a variable, and more often these variables are distilled at a very high level abstraction for analysis. Leadership functions, the number of administrative levels… but there’s never a sense in processual archaeology (in my view) for how it is through people’s actions that these variables emerge and these high levels came to be. I thought this was a major flaw in processualism

If you look at post-processulism, at its worst people like Tilley and Shanks in the early 1990s, you have this view of agency… People are acting almost without structures. There’s no predictability to their actions. No sense of optimality or adaptation that structure their actions. Although I would admit that these positions did have the effect of exposing some of the weaknesses in processual archaeology, they didn’t offer a positive program to make a path going forward to understand prehistory.

I thought what was needed was a way to think about the archaeological record as being composed of the actions of agents, while giving the proper role to these sorts of structures that these agents had to operate within (people within societies). I also thought that a proper role needed to be given to concepts like evolution and adaptation that were out the window for the early post-processualists. That is what complexity in archaeology tries to achieve. A complex-adaptive system approach honors actions of individuals but also honors that agents have clear goals that provide predictability to their actions, and that these take place within structures, such as landscapes or ecosystems or cities, that structure these in relatively predictable ways.

How does complexity help you understand your system of interest?

Complexity approaches give us the possibility to examine how high-level outcomes emerge from the outcomes of agent-landscape interaction and agent-agent interaction. These approaches to a great measure satisfy the weaknesses of those the two main approaches from 90s (processualism and post-processualism). So we have both high level outcomes (processualism) and agent level actions (post-processualism) but complexity provides a bridge between these two.

What are the barriers we need to break to make complexity science a main-stream part of archaeology?

Obviously barriers need to be broken. Early on, although this is not the case as much any more, many students swallowed the post-processual bait hook, line and sinker, which made it so they wouldn’t be very friendly to complexity approaches. They were, in a sense, blinded by theoretical prejudices. This is much less true now, and becomes less true each year. The biggest barrier now to entry is the fact that very few faculty are proficient in the tools of complex adaptive systems in archaeology, such as agent based modeling, scaling studies, and faculty even are not proficient with posthoc analyses in tools like R that make sense of what’s going on in these complex systems. Until we get a cadre of faculty who are fluent in these approaches this will be a main barrier.

Right now the students are leading the way in complex adaptive systems studies in archaeology. In a way, this is similar to how processual archaeology started—it was the students who led the way then too. Students are leading the way right now, and as they become faculty it will be enormously useful for the spread of those tools. So all of these students need to get jobs to be able to advance archaeology, and that is a barrier.

Do you think that archaeology has something that can uniquely contribute to complexity science (and what is it)?

I would make a strong division between complex adaptive systems (anything that includes biological and cultural agents) and complex nonadaptive systems (spin glasses, etc.) where there is no sense that there is some kind of learning or adaptation. Physical systems are structured by optimality but there is no learning or adaptation.

The one thing that archaeologists have to offer that is unique is the really great time depth that we always are attempting to cope with in archaeology.

The big tradeoff with archaeology is that, along with deep time depth, we have very poor resolution for the societies that we are attempting to study. But this gives us a chance to develop tools and methods that work with complex adaptive systems specifically within social systems; this, of course, is not unique to archaeology, as it is true for economists, biologists, and economists

What do you think are the major limitations of complexity theory?

I don’t think complexity approaches, so far at least, have had much to say about the central construct for anthropology—culture. Agent-based models, for example, and social network analysis are much more attuned to behavior than to culture. They have not, so far, tried to use these tools to try to understand culture change as opposed to behavioral change. It’s an outstanding problem. And this has got to be addressed if the concept of culture remains central to anthropology (which, by definition, it will). Unless complexity can usefully address what culture is and how it changes, complexity will always be peripheral. Strides have been made in that direction, but the citadel hasn’t been taken.

Does applying complexity theory to a real world system (like archaeology) help alleviate the limitations of complexity and make it more easily understandable?

Many people who aren’t very interested in science are really interested in archaeology. So I think archaeology offers a unique possibility for science generally, and complexity specifically, by being applied to understanding something that people are intrinsically interested in, even if they aren’t interested in other applications of same tools to other problems. It’s non-threatening. You can be liberal or conservative and you can be equally interested in what happened to the Ancestral Puebloans; you might have predilection to one answer or another, but you are still generally interested. But these things are non-threatening in an interesting way. They provide a showcase for these powerful tools that might be more threatening if they were used in an immediate fashion.

What do you recommend your graduate students start on when they start studying complexity?

Dynamics in Human and Primate Societies by Kohler and Gummerman is a useful starting point

I am a big enthusiast for many works that John Holland wrote

Complexity: A Guided Tour by Melanie Mitchell’s is a great volume

I learned an enormous amount by a close reading of Stu Kauffman’s “Origins of Order.” I read this during my first sabbatical at SFI, and if you were to look at the copy you’d see all sorts of marginal annotations in that. We don’t see him cited much nowadays, but he did make important contributions to understanding complex systems.

In terms of technology or classes, the most important things would be for them to get analytical and modeling tools as soon as they could and as early as they can. In the case of Washington State University, taking agent-based modeling course and taking the R and Big Data course would be essential. But to be a good archaeologist you need a good grounding in method and theory, so taking courses that fulfill that as early on as possible is essential.

And a final question…

What are two current papers/books/talks that influence your recent work?

I’m always very influenced by the work of my students. One of my favorites is the 2014 Bocinsky and Kohler article in Nature Communications. Another is upcoming foodwebs work from one of my other students. These papers are illustrative of the powers of complexity approaches. Bocinsky’s article is not in and of itself a contribution to complex adaptive systems in archaeology, except that it is in the spirit of starting off from a disaggregated entity (cells on a landscape) and ending up with a production sequence emerging from that for the system as a whole. It shows how we can get high-level trends that can be summarized by amounts within the maize niche. So it deals, in a funny way, with the processes of emergence. It’s a prerequisite for doing the agent-based modeling work.

Some recent works by Tim Kohler

2014 (first author, with Scott G. Ortman, Katie E. Grundtisch, Carly M. Fitzpatrick, and Sarah M. Cole) The Better Angels of Their Nature: Declining Violence Through Time among Prehispanic Farmers of the Pueblo Southwest. American Antiquity 79(3): 444–464.

2014 (first author, with Kelsey M. Reese) A Long and Spatially Variable Neolithic Demographic Transition in the North American Southwest. PNAS (early edition).

2013 How the Pueblos got their Sprachbund. Journal of Archaeological Method and Theory 20:212-234.

2012 (first author, with Denton Cockburn, Paul L. Hooper, R. Kyle Bocinsky, and Ziad Kobti) The Coevolution of Group Size and Leadership: An Agent-Based Public Goods Model for Prehispanic Pueblo Societies. Advances in Complex Systems15(1&2):1150007.

2012 (first editor, with Mark D. Varien) Emergence and Collapse of Early Villages: Models of Central Mesa Verde Archaeology. University of California Press, Berkeley

Simulating Complexity at the SAA meetings!

Hello readers! I’m writing you from sunny San Francisco where we are gearing up for the SAAs. We have a Simulating Complexity session that is sure to be interesting. Find us Thursday afternoon at 1pm in the room Union Square 21. Here’s a teaser of the paper titles.

Opening Remarks–Mark Lake

A spatially explicit model of lithic raw material composition in archaeological assemblages–Phil Fisher and Luke Premo

Simulating Late Holocene landscape use and the distribution of stone artefacts in arid western New South Wales, Australia–Benjamin Davies

Testing the Variability Selection Hypothesis on Hominin Dispersals – a Multi-agent Model Approach–Iza Romanowska and Seth Bullock

Climatic variability and hominin dispersal: the accumulated plasticity hypothesis–Matt Grove

Humanizing wave of advance dispersal models–Colin Wren

Hierarchy and Tribute Flow in the American Southwest–Stefani Crabtree, Kyle Bocinsky, Tim Kohler

Changing Channels: Simulating Irrigation Management on Evolving Canal Systems for the Prehistoric Hohokam of Central Arizona–John Murphy, Louise Purdue, Maurits Ertsen

Complexity in space and time: spatio-temporal variability and scale in simulations of social-ecological systems–Isaac Ullah & Michael Barton

Modeling Behavior in Digital Places Using Low-Level Perceptual Cues–Rachel Opitz

Reconstructing Large-Area Ancient Transportation Networks to Support Complexity Research–Devin White

Many Roman Bazaars: exploring the need for simple computational models in the study of the Roman economy–Shawn Graham & Tom Brughmans

Empirical Validation and Model Selection in Archaeological Simulation–Enrico Crema

Discuassant and closing remarks–Tim Kohler