Showing posts with label Models. Show all posts
Showing posts with label Models. Show all posts

Friday, November 28, 2025

Integration of Community Level Data into Mathematical Models

In the past we have posted about how we can utilize data and models to explore pandemics and peoples reactions to them. And while interest in the COVID might of waned, there will be future pandemics. 

To this end, at the 53rd Annual Meeting of NAPCRG we (Laurene Tumiel Berhalter, Sanchit Goel, Dawn Vanderkooi, Bruce Pitman, Yinyin Ye,  Jennifer Surtees and myself) had a poster entitled "Integration of Community Level Data into Mathematical Models to Predict Future Public Health Emergencies." The objective of the poster is to showcase how one can integrate 211 data into models to predict future public health emergencies. If this sounds of interest, below you can see the poster and at the bottom of the post you can access the abstract. 


Full Reference:

Tumiel, L.M., Goel, S., Vanderkooi, D., Pitman E.B., Crooks A.T., Ye, Y. and Surtees, J. (2025), Integration of Community Level Data into Mathematical Models to Predict Future Public Health Emergencies, North American Primary Care Research Group (NAPCRG) 53rd Annual Meeting, 21st-25th November, Atlanta, GA (pdf).

Wednesday, January 02, 2019

Models from Teaching CSS Fall 2018

Most of the time when I teach a class instead of setting a final exam, I ask the students to carryout an end of semester research project. In my Introduction to Computational Social Science class this project entails the development of a computational model in an area of  interest to the student . The aim of this exercise is to cement what the students have (hopefully) learnt during the semester. I.e.: 
  • to understand the motivation for the use of computational models in social science theory and research; 
  • to learn about the variety of CSS research programs across the social science disciplines; 
  • to understand the distinct contribution that CSS can make by providing specific insights about society, social phenomena at multiple scales, and the nature of social complexity.
Below you can see some of the outputs from these projects this last fall. The models range in type from agent-based models, microsimulation to system dynamics models applied to a variety of topics from voting and political parties, the peer effects of students, urban decline, employment growth and rise and fall of civilizations and many other topics along the way.


Monday, December 10, 2018

Talk: Computational Modeling of Slums: Progress & Challenges

Last week I gave a talk to Department of Computational and Data Sciences colloquium series entitled to "Computational Modeling of Slums: Progress and Challenges" in which I discussed some of our current work on slums. This talk was inspired by several of the papers we have written or currently writing on slums As we live stream and store these talks on YouTube, I thought I would share this one here (apologies about the sound quality).

Abstract:
Over the last 50 years the world has increasingly become more urbanized, much of this growth has occurred in less developed countries, which often lack the resources to accommodate such growth. This has led to the growth of slums, which is estimated to be home for other 1 billion people. The UN-Habitat projects slum population to double by 2030, which would make them home for 2 in 5 people living in cities. In this talk I will introduce slums, discuss their growth, and provide an overview on what progress has been made to studying and modeling them. This will lead to a discussion of a series of key challenges that need to be addressed if we are to tackle slums from a computational perspective.


Wednesday, December 21, 2016

A semester with CSS

This last semester I gave both a graduate and undergraduate course in Computational Social Science (CSS). Both courses survey computational approaches such as system dynamics, social network analysis, machine learning, cellular automata, discrete event simulation, agent-based modeling, and microsimulation to study social phenomena with emphasis on complexity theory.

For the undergraduate class, we met twice a week. In the first class of each week I would outline the topic,  discuss a specific modeling approach and give a range of sample applications. While the second class of the week was devoted to hands on model development (I chose to use NetLogo for this), in order to cement what was discussed in the first class (a learning by doing if you like.). For example, one week we discussed cellular automata (CA) modeling, where in the first class, I outlined its evolution, its basic proprieties and applications (e.g. from simple voting models to that of urban growth). In the second class, the students then built a CA model from scratch.  For the graduate class, more emphasis was placed on theory, critiques of modeling and discussion of key texts.

In both classes, all the students needed to carry out a project where they develop a computational model that investigates a social science research question. This exercise is often their first model (especially for the undergraduates) that many students ever create. Below you can see some of this years models.


Monday, November 28, 2016

New Paper: Close, But Not Close Enough



At the 2016 The Computational Social Science Society of Americas Conference,  Tom Briggs and myself had a paper accepted entitled "Close, But Not Close Enough: A Spatial Agent-Based Model of Manager-Subordinate Proximity". In the paper we present our  preliminary effort to explore how workplace layout impacts on subordinates interactions with managers. We developed a spatial agent-based model to simulate how the physical seating locations of individuals with reporting relationships might enhance or detract from an effective manager-subordinate relationship. Below you can read the abstract of our paper and find out more information about the model.


Abstract:
Employees may be co-located with their manager or they may be separated by distances ranging from a short walk to across oceans, with many gradations in between. Some distances, such as those between floors of an office building, are physically short but may be psychologically quite far. The current project developed a spatial ABM to examine the likelihood of unplanned manager-subordinate encounters in an office setting with two floors. Early results suggest that subordinates located on a different floor than their manager are substantially less likely to have even a single spontaneous encounter with their manager in a work day, despite a relatively short physical separation. If leader-follower (i.e., manager-subordinate) relationships are influenced by spontaneous face-to-face encounters, this finding represents a challenge for organizations with managers having subordinates who are close, but not close enough. Additionally, attempting to impose top-down requirements to travel between floors (e.g., when scheduling meetings) may do surprisingly little to abate this problem. Implications of these findings for organizations are discussed, as are limitations and future research, including possibilities for future model verification and validation.

Keywords: workplace design, supervision, leadership, management, employee performance, virtual teams, leader distance, collaboration, agent-based modeling, ABM



Full Reference:
Briggs, T. and Crooks, A.T. (2016), Close, But Not Close Enough: A Spatial Agent-Based Model of Manager-Subordinate Proximity. The Computational Social Science Society of Americas Conference, Santa Fe, NM.  (PDF)
Click here to download the model.

Wednesday, December 11, 2013

Book review: A Framework for Geodesign:

Recently I had the pleasure of reading and reviewing the book entitled "A Framework for Geodesign: Changing Geography by Design" by Carl Steinitz. The full review can be found in Environment and Planning B. However, I thought I would share the review to readers of the blog (with some added images).

"People have designed and changed the geography of their landscapes for thousands of years, for the better or for the worse. But with more pressure being placed on the world’s resources, with increasing numbers of people, the question that we are now faced with is, what are the best sustainable design solutions to mitigate these challenges? For example, urban growth is inevitable given the increasing concentration of people living within in cities, and as a trend is expected to continue into the foreseeable future. The question that designers and planners are therefore faced with is what scenarios would lead to say the least amount of loss in biodiversity. But this is a multi-faceted problem ranging in scale from how do people build there homes, to where should new industry be located, or how should land be conserved etc? These are all questions involving spatial decision-making, and where geographic information systems can play an important role. Over the last forty years, geographic information systems (GIS) have increasingly been used to assist in such complex decisions, from modelling urban growth projections through to assessing the spread of pollution (see Longley et al., 2010 for a extensive list of applications). However, one of the original visions for GIS, which is often overlooked, is that of a tool for design (Goodchild, 2010).

In his book “A Framework for Geodesign: Changing Geography by Design” Karl Steinitz brings his vast experience as a landscape architect and planner to such an issue. For those not familiar to the term geodesign, Steinitz (2012) writes in his preference to the book that it “is an invented word, and a very useful term to describe an activity that is not the territory of any single design profession, geographic science or information technology” (p ix). More generally Steinitz (2012) frames geodesign as “the development and application of design-related processes intended to change the geographical study areas in which they are applied and realised” (p1). Or another way of putting it, the merging of geography and design through computers. This is reiterated later on by a quote from Michael Flaxman were he states “Geodesign is a design and planning method which tightly couples the creation of design proposals with impact simulations informed by geographic contexts, systems thinking, and digital technology” (Flaxman quoted in Steinitz, 2012 p 12).

Moreover, geodesign can be considered both as a verb and as a noun which Steinitz relates to design more generally (see Steinitz, 1995). In the sense as a verb, geodesign is about asking questions and as a noun, geodesign is the content of the answers. In this book Steinitz not only clears up the meaning of geodesign but more importantly provides a comprehensive framework (based on his past work) for thinking about strategies of geodesign, and for organising and operationalizing these meanings.

The book is made up of twelve chapters and split into four parts. The first part is spent on framing geodesign and to set the scene for the remainder of book. For example, chapter 1 notes that for geodesign to be successful, one requires collaboration between the design professions (e.g. architects, planners, urban designers, etc.), geographical sciences (e.g. geographers, ecologists, etc), information technologies and those people living within the communities where geodesign is being applied. This is reiterated throughout the book. Chapter 1 also traces the history of geodesign, and how the advent of computer methods for the acquisition, management and display of digital data can be used to link many participants, thus making design not a solitary activity. Chapter 2 introduces the reader to the context for geodesign in the sense that 1) geography matters and that different societies think differently about their geography, 2) scale maters in the sense of what scale should a geodesign project be applied at (e.g., local, regional or global), and what are the appropriate considerations that need to incorporated at each scale, and finally 3) size matters, if the size of the geographic study area increases, there is a high risk of a harmful impact if one makes a mistake.

Part 2 of the book lays out a framework for geodesign. It is important to note that Steinitz does not call this a methodology for geodesign, as he argues one cannot have a singular methodology as the approaches, principles and methods are applied to projects across a range of geographies, scales and sizes. He therefore introduces a framework as a verb, specifically for asking questions, choosing among many methods and seeking possible answers. In order to develop this framework Steinitz walks the reader through six different questions and types of models common in geodesign projects.

Chapter 3 focuses on components of the framework and the questions one needs to address for a successful geodesign project. These questions broadly range from: 1) How should the study area be described? 2) How does the study area operate? 3) Is the current study area working well? 4) How might the study area be altered? 5) What differences might the changes cause?, and finally, 6) How should the study area be changed? As posed by Steinitz, these questions are not a linear progression, but have several iterative loops and feedbacks both with the geodesign team and the application stakeholders. Moreover, Steinitz argues that such questions should be asked three times during the geodesign study, the first to treat them as why questions (e.g. to understand the geographic study area and the scope of the study). Secondly, the questions are asked in reverse order to identify the how questions (e.g. to define the methods of the study, therefore geodesign becomes a decision rather than data driven process) and finally, the questions are asked in sequential order to address the what, where and when questions as the geodesign study is being implemented. Once these three iterations are complete, there can be three possible decisions, yes, no and maybe. If maybe or no, more feedback is needed between the geodesign team and the stakeholders. These iterations highlight how geodesign is an on-going process of changing geography by design.


Using this framework, Chapter 4 discusses the first iteration of questions, that of scoping the geodesign study. The emphasis of this iteration is ensuring that it is being decision-driven as opposed to data-driven. Moreover, it goes over the six questions in an attempt to identity the intended scope for the study before looking at a feasible methodological plan. Chapter 5, moves onto the second iteration, that of designing the study methodology. Having identified the scope of the study (the why) from the first iteration, the geodesign team must then explore how it will be carried out and what are the evaluation criteria. Chapter 6 discusses the third iteration, that of carrying out the geodesign study. That of the what, where and when questions. Throughout these chapters, Steinitz reiterates the need for stakeholder input and feedback from the geodesign team. Moreover, at the end of chapter 6, Steinitz reiterates that the choices mater. The why questions provide a sense of the scope and objectives of the design application: the problem, the study area and those scales required for operationalizing a successful project.

Part 3 of the book looks at nine case studies in geodesign from around the world. Ranging in temporal scale from days to years, from no financial budget to a large budget, and from a small to large numbers of participants. These case studies helped solidify many of the concepts identified in the preceding chapters. They range from urban growth, to urban change to that of fire management. The case studies focus on specific places and utilize GIS with a variety of different techniques, from anticipatory modelling to that of participatory modelling and rule based models (e.g. cellular automata). They also show the importance of visualisation, as Steinitz (2012) notes “spatial visualisation can significantly influence decision making” (p 168). These examples have details but not depth (however, references are given to the full case study report), but this reiterates the purpose of the book, in the sense it is not a “how to” textbook or listing technologies that enable geodesign. It is a discussion with examples of geodesign. Or to quote from the last page of the book “you cannot copy an example but you can gain experience by joining the collaborative activities of geodesign and changing geography by design” (Steinitz, 2012, p 201). The same goes for the applications, they give a valuable insight into what is possible with geodesign. The book concludes by discussing the future applications for geodesign which range from looking at the implications for research in geodesign, and sketching out a geodesign support system (see Ervin, 2011); and in a sense, one could relate this to other planning support systems (see Brail, 2008), but with a greater emphasis on design.

Overall the book is extremely well written and Steinitz provides a critical and personal account of geodesign, which shows his expertise in the area from his years of teaching and carrying out geodesign work. The use of figures and real world examples really helps support the discussion. But if you are looking for a textbook for “how to” do geodesign, or a list of technologies that enable geodesign, you need to look elsewhere. This is a book the principles and practice of geodesign in a general sense, and which provides a valuable resource for those interested in this topic."

References:
Brail, R.K. (ed.) (2008), Planning Support Systems for Cities and Regions, Lincoln Institute of Land Policy, Cambridge, MA.
Ervin, S. (2011), 'A System for GeoDesign', Proceedings of Digital Landscape Architecture, Anhalt University of Applied Science, Dessau, Germany, pp. 145-154.
Goodchild, M.F. (2010), 'Towards Geodesign: Repurposing Cartography and GIS?.' Cartographic Perspectives, 66(7-22).
Longley, P.A., Goodchild, M.F., Maguire, D.J. and Rhind, D.W. (2010), Geographical Information Systems and Science (3rd Edition), John Wiley & Sons, New York, NY.
Steinitz, C. (1995), 'Design is a Verb; Design is a Noun', Landscape Journal, 14(2): 188-200.
Steinitz, C. (2012), A Framework for Geodesign: Changing Geography by Design, ESRI Press, Redlands. CA.
Full reference to the book:
Review of Steinitz, C. (2012), A Framework for Geodesign: Changing Geography by Design, ESRI Press, Redlands. CA.
Full reference to the review:

Crooks, A.T. (2013), Crooks on Steinitz: A Framework for Geodesign: Changing Geography by Design, Environment and Planning B, 40 (6): 1122-1124.