Each student was encouraged to pursue a project that extended one of the models discussed during the semester. Challenging authors' assumptions by implementing their own models, students gained facility with technical concepts and competence with modeling techniques.
Residential Segregation
Extending the work of Schelling, David Siegel developed a residential segregation model that incorporates an irregular lattice structure (Voronoi Diagram) and a sigmodial decision algorithm. Combined with Schelling's minimal assumptions about preferences, this model shows that residential segregation still emerges even with these extensions.
Schelling Sigmoidal Screen Shot
Following ideas charted by Mark Fossett's "Sim Seg" program (http://www.amberwaves.com/simseg/index.htm), Steve Benard relaxed Schelling's assumption of perfect accessibility of preferred housing options. Agents are constrained in their search for housing by both wealth and status, allowing the modeler to manipulate the affordability of housing and the distribution of wealth. Findings include a non-linear effect of affordability on class segregation, as well as suburbanization-like patterns showing dense central clusters of poor agents surrounded by rings of wealthier agents.
Schelling Wealth and Status Screen Shot
Cultural Diffusion
David Lifson and Paul Lee extended Axelrod's cultural diffusion model by incorporting concepts from cultural ecology. By introducing heterogeneity into the model, in the form of social 'innovators', they explored the effect of cultural leaders on the local dynamics of cultural evolution.
Axelrod Cultural Ecology Screen Shot
Grade Inflation
Cyprian Wejnert's project goes beyond the problems studied in the course to develop a model of grade inflation.
In the model, "students" adjust their effort-level based on their previous grades and their expectations for these grades. "Graders" also adjust their grading curve to match the grades given in past courses, and students selectively choose classes based on their experience with graders. The model shows that grade inflation can easily emerge under a variety of conditions.
Grade Inflation Screen Shot
