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Analysis of distance along a network

December 05 2011 | 0 comments
Categories: ArcGIS 10

Hi there. I am trying to analyse average distances from properties to their nearest bus stops, "forced" along a footpath network. The reason for this is that we often look at how far people live from bus stops "as the crow flies", resulting in a type of query along the lines of "How many properties (or the centroids of those properties) fall within a 500 metre radius of our bus stops." However, the nature of the network that people are forced to use to get to those bus stops means that, particularly when we deal with cul de sacs and highly impermeable neighbourhoods, people must travel significantly further than a straight line. I am having difficulty attempting to resolve this question in Arc (and in Quantum and MapInfo for that matter, although ArcGIS is my go to platform). Do you have any ideas on how this query could be executed: "What are the route distances from each point layer A (property centroid) to the closest point from point layer B (bus stop locations), when those routes are forced to travel along polyline layer C (foot path network). I have attached a picture of this query - purple is bus stops, green is property centroids, and black lines are footpaths.

Your help would be greatly appreciated!

### Mapping Center Answer:

The tools you would use to tackle this sort of analysis are available in the Network Analyst extension.  Performing analysis along a route will allow you to determine the actual distance along the network between a person's home and a bus stop so you can determine the shortest path between each house and the nearest bus stop. Once you have that solved, you can calculate the average of all (or a subset) of homes.

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