TITLE: Schelling bound and unbound: modeling residential segregation with 
complex spatial structure

ABSTRACT: Thomas Schelling's simple models of residential segregation have 
been influential -- perhaps the most influential agent-based models in 
social science.  However, most agent-based models derived from Schelling's 
work focus attention on only one aspect of his work, that of a 
'checkerboard' of continuous local neighborhoods.  Schelling also did 
analytical work based on a bounded neighborhood representation.  A 
variation on Schelling's model of residential location dynamics that 
combines his two concepts of neighborhood is described.  This model allows 
(i) exploration of the impact of local versus neighborhood level effects, 
and (ii) generalization of the spatial structure of the model to arbitrary 
geographic units, not just a simple grid.  Preliminary results are 
reported, which show that the geographic scale of the bounded neighborhoods 
considered by agents in making residential location decisions has important 
impacts on overall model outcomes.  Several directions for further work 
will be discussed.