topic Re: when you are using Linear, Power, Exponential? in ArcGIS Network Analyst Questions

when you are using Linear, Power, Exponential?

GustavoCordero — Thu, 11 Jun 2015 22:22:04 GMT

I'm using Arcgis 10.3

I am new to using the (Location-allocation analysis) of network analist

I have a question with, "Impedance Transformation"

I have read the help of http://resources.arcgis.com

but I do not quite understand when and how to use "Impedance Transformation"

when you are using Linear, Power, Exponential?

if you have docuementacion you can help me understand the use of "Impedance Transformation" would be very grateful

Re: when you are using Linear, Power, Exponential?

DanPatterson_Retired — Thu, 11 Jun 2015 22:47:29 GMT

From the location allocation desktop help on this topic

Demand points have an ImpedanceParameter property, which, if set, overrides the Impedance Parameter property of the analysis layer. You might determine that the impedance parameter should be different for urban and rural residents. You can model this by setting the impedance transformation for the analysis layer to match that of rural residents and setting the impedance transformation for the demand points in urban areas to match that of urbanites.

which suggests that you can apply a transformation if you suspect that there is a difference in the behaviour of different areas and/or groups. This of course would have to be justified based upon some other analyses, so unless you know otherwise, then you would have to assume that demand etc is equal across the landscape/individuals and no transformation would be needed.

Re: when you are using Linear, Power, Exponential?

GustavoCordero — Fri, 12 Jun 2015 14:44:12 GMT

Dan Patterson thanks for your answer

I have two questions

1) If I do not set in (demand points) ownership (ImpedanceParameter) and assume that demand is the same throughout the landscape / individuals

serious ImpedanceParameter equal to (linear)?

2) how establish in (demand points) the ownership (Impedance Parameter)

Re: when you are using Linear, Power, Exponential?

DanPatterson_Retired — Fri, 12 Jun 2015 15:11:22 GMT

During the creation of the network for those purposes,...otherwise details may be given in the Network Analyst Tutorial but it has been some time since I have done this