Spatial Network Analysis


Nicholas Martino
nicholas.martino@hotmail.com

Spatial Network

A graph whose edges and nodes are spatial elements

Types of spatial network analysis

Shortest paths: one element in relation to another

Centrality: all elements in relation to each other

Service area: reach from an element along the network

Walkability case study

Walkability is the ability of spaces to support walking in detriment of other transport modes.
Elements located within walkable distances tend to influence how much people walk.

Why Walkability?

Walkable places have:

  • higher rates of physical exercise;
  • lower rates of obesity and heart diseases;
  • more social interaction and diversity;
  • more safety from traffic accidents

How to Measure Walkability?

Walkability is inherently a spatial concept, thus it can be measured by spatial attributes, such as:

1. Population Density

2. Street Network

3. Land Use

Walkability Indices

Index = Indicator1 + Indicator2 + ... + IndicatorN

Walkability Index: a set of indicators that represents people's tendency to walk

  • Neighborhood Quality on US cities (Frank et al. 2010)
    • Intersection density
    • Residential density
    • Retail floor area ratio
    • Land use mix

Cities are complex non-linear systems

Walkability indices represent probabilistic patterns of human behaviour

Tools and Resources

Geographic information system (GIS) application for viewing, editing and analyzing geospatial data

  • Free and open source software;
  • Good set of free plugins;
  • Intuitive interfaces;
  • Runs on Linux, Windows and Mac.

Samples: Urban blocks of 3 neighborhoods in Vancouver

Source: City of Vancouver

Indicators: Street Network + Business Licenses + Population Density

Source: OpenStreetMap + City of Vancouver + Statistics Canada

Method: Network analysis

Output: Walkability index