01137486

Component

The rising awareness of the built environment and urban design’s influence on health and human behavior has encouraged efforts to characterize the environment through subjective summary measures. This paper focuses on the existing summary measures of "connectivity," the term used to measure the concentration of links between locations in a neighborhood. These measures include the alpha, beta, gamma and Smart Growth Index’s connectivity indices, based on actual to theoretically maximally connected street nodes. This paper explores the ability of each of these measures to describe adequately an environment’s connectivity. ArcView’s Network Analyst tool was used to create a 1km street network-based neighborhood around 112 public schools in the city of San Francisco. Several indices were calculated for each neighborhood to identify the most and least connected regions. These measures were then compared with each other as well as with the total street network length accessible within the neighborhood of the schools. The results suggest that the indices may give false results in areas with “hyper-connectivity”— a high density of short dead-end streets embedded within the basic street grid network—arguably making total street network length a better summary connectivity measure for a street or path constrained network.

01120148

09-3769

English

15p

2009

Transportation Research Board 88th Annual Meeting

DVD

Figures (3) ; References (28) ; Tables (1)

Accessibility; Geographic information systems; Neighborhoods; Network links; Network nodes; Residential streets

Data and Information Technology; Highways; I10: Economics and Administration

Transportation Research Board Annual Meeting 2009 Paper #09-3769

BTRIS, TRIS, TRB

Jan 30 2009 8:11PM