Inferring areal geographies of named populated places in Connecticut

1. Inferring areal geographies of named populated places in Connecticut Patrick McGlamery University of Connecticut Libraries

2. The ppl feature type in GNIS ppl (populated place) – place or area with clustered or scattered buildings and a permanent human population (city, settlement, town, village).

3. Satisficing Connecticut's ppls “Satisficing has been defined by Simon (1979) as a psychological form of the law of diminishing returns – we do not seek optimal solutions to certain problems because the costs are too high, so we settle for solutions that are satisfactory given the cost.” Only towns, the primary unit of civil administration in Connecticut, have boundaries. All of the ppls are represented as points. Therefore areas need to be determined for these places in order to generate a footprint.

4. Named populated places in Connecticut 718 unbounded populated places, “ppl” 169 town civil divisions

5. Inferring areas for GNIS ppls Working from classed 1995 30m cell satellite imagery and ppls from the GNIS, areal boundaries were determined based on five Land Use / Land Cover classes which describe a built environment. • Commercial & Industrial • Residential • Rural Residential • Tree & Turf Complex • Tree & Grass Complex

6. Ppl with no area Land Use / Land Cover Land Use / Land Cover with Town boundaries and ‘ppl’ Land Use / Land Cover with Town boundaries Land Use / Land Cover with built environments population classes aggregated and joined to ppl

7. Process observations • Successful inferences resulted in a single ppl point per polygon. (258 of 718) • Unsuccessful inferences resulted in: • Multiple ppl points per polygon (193 of 718) • Ppl points with no polygon (267 of 718)

8. Multiple inferences of ppl areas 193 of 718 All ppls 718 Unsuccessfully inferred ppl areas 267 of 718 Successfully inferred ppl areas 258 of 718

9. Multiple ppl points per polygon Are a result of urban sprawl. Ursprawl in Connecticut creates a continuous urban landscape along the coast and up the I91 corridor. The ppls in the sprawl may still be discrete places, or may have faded from the public notion of a named place and reside only on a map.

10. ppl in GNIS, but no built environment The ppl is off-set from the crossroads and from the built environment. Podunk, a nowhere place in Connecticut. But the populated place of Guilford, is not a ppl and so is not an inferred area. Or, the Town of Guilford, which is a civil division and is large. In fact, Podunk appears to really be in the sticks. or, built environment, but no ppl.

11. Conclusions • Bounding boxes of point data (ppl) are points. • Spatial data can be processed to satisfice footprints in Connecticut, but requires local authentication. • We cannot assume, a priori, that the GNIS reflects named places in Connecticut.