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dasymetric mapping

January 09 2009 | 3 comments
Categories: ArcGIS Methods, Map Data, Symbology

How do I go about performing dasymetric analysis in ArcInfo?

Thanks

Mapping Center Answer:

So, this is a bit beyond the scope of just a simple question and answer exchange.  In some ways this is the meat and potatoes of GIS--the overlay commands in the toolbox are a good place to start--essentially, you're trying to winnow down set of areas to just the portions of each polygon that include what is relevant to you. 

In the basic sense of dasymetric analysis, the Union tool would be a simple way to start--If you Union your polygon data with polygon features that represent areas that you want excluded, then you have the basis for a query to select non-relevant areas from the Union result and delete them.

Also, in the dot density symbology, if you click on the Properties button (just above the Exclusion button) you can check on the option to "Use Masking", which performs a rudimentary dasymetric operation on the dot symbols by either restricting the dots to, or excluding the dots from the polygon dat you specify as the control layer.

dasymetric maps posted by Jeremy Mennis on Jan 12 2009 9:31AM
You should try this script for ArcGIS 9.2 by Rachel Sleeter:

http://geography.wr.usgs.gov/science/dasymetric/data.htm

Or you can implement the steps themselves in ArcGIS as specified in my paper at:

http://astro.temple.edu/~jmennis/pubs/mennis_pg03.pdf

Or you can use some easy to basic dasymetric steps as described by Mitchel Langford:

Mitchel Langford: Rapid facilitation of dasymetric-based population interpolation by means of raster pixel maps. Computers, Environment and Urban Systems 31(1): 19-32 (2007).

I don’t know of any other readily available dasymetric mapping scripts out there.

Hope this helps! - jeremy
Just finished my Dasymetric model posted by David VandenBos on Feb 13 2009 10:09AM
I just completed a Dasymetric model using the links that Jeremy provided. The USGS add-in gave me a bit of trouble on 9.3 so I just followed Jeremy's methodology, especially pages 36-38 in his paper. Just took a little time and a lot of field calculator. I was able to use census block and parcel info (from the county auditor) for my areal interp.
Excellent! posted by Aileen Buckley on Feb 13 2009 10:12AM
So glad this worked for you! It is a bit complicated, as you note, but then dasymetric mapping of any kind IS! Congratulations!

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