The emergence and evolution of OpenStreetMap: a cellular automata approach

Figures & data

Figure 1. Common representations of CA models and first- and second-order neighborhood functions (von Neumann and Moore neighborhoods).

Figure 2. Spatial extent of the study site, Heidelberg.

Figure 3. The land-use map of Heidelberg provided by ATKIS.

Figure 4. Schematic workflow of CA modeling.

Figure 5. Trends of OSM contributions (nodes).

Table 1. Summary of temporal trends of the contributors and their contributions.

	Year
	2007	2008	2009	2010	2011	2012
Number of contributed nodes	7	2266	6637	9318	38536	53680
Number of cells representing contributions	7	808	2436	3428	7614	8640
Average number of node per cell	7	2.8	2.7	2.7	5.1	6.2
Percentage of occupied cells	0.05	5.59	16.85	23.71	52.67	59.77
Number of contributors	3	15	55	96	148	243
Rate of Contributions (node/person)	2.3	53.9	44.3	35.7	51.4	35.6

Figure 6. Spatio-temporal representation of contributions for each timestamp.

Table 2. CA calibration results for several iterations and different years.

Base time stamp	2009			2010		2011
Predicted year	2010	2011	2012	2011	2012	2012
Iteration 1	83.48	28.31	15.3	42.03	29.44	82.69
Iteration 2	84.01	27.92	15	41.66	29.21	83.37
Iteration 3	83.69	27.82	15.18	41.56	29.36	83.19
Iteration 4	83.72	27.88	15.23	41.67	29.5	83.36
Iteration 5	83.72	27.93	15.32	41.67	29.52	83.33
Iteration 6	83.69	27.93	15.34	41.7	29.58	83.33	Kappa index %
Iteration 7	83.66	27.96	15.37	41.71	29.59	83.33
Iteration 8	83.66	27.96	15.37	41.7	29.58	83.33
Iteration 9	83.66	27.96	15.37	41.7	29.58	83.33
Iteration 10	83.66	27.96	15.37	41.7	29.58	83.33

Figure 7. CA prediction for 2014.