[CTPP] TAZ Development

[Sam.Granato at dot.state.oh.us]

Mr. Paddock:

It's safe to say that one set of TAZs will not be able to cover both these 
needs for you.  There's been discussion here before about developing two 
or more sets of TAZs just for different levels of disclosure problems with 
2010 CTPP (ACS) data alone.  You'll need at least one more set for traffic 
modeling, where you can geocode the address-based, Census block and other 
small area data not subject to these disclosure problems and than from 
there aggregate to the level needed for the model.


Sam Granato
Ohio DOT, Office of Multi-Modal Planning
1980 W. Broad Street, Columbus, OH  43223
Phone:  614-644-6796, Fax:  614-466-0822
"It's all very well in practice, but it will never work in theory." - 
French proverb

I must admit that, of late, I have gotten lost in the woods while trying 
to see all the trees.  During these past months I have been engaged in 
developing a new TAZ system for the Minneapolis - St. Paul MPO area that 
will both serve the needs of travel demand modeling here at the 
Metropolitan Council AND provide us with the information we want from a 
2010 CTPP-like product.

This new TAZ system is substantially more refined than those of the past 
and should result in reasonable travel loadings on our arterial roadway 
network.  However, certain issues have been raising their knobby heads 
regarding zone size that probably will clash with Census Disclosure Board 
rules.  Does anyone have a reasonable idea as to what minimum population 
or household levels a TAZ will need to attain in order to circumvent large 
numbers of "blank" cells?  I suspect that there is not an easy, 
uncomplicated answer but would like to hear one nonetheless.


Bob Paddock
Transportation Planning
Metropolitan Council
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://www.chrispy.net/pipermail/ctpp-news/attachments/20090805/93305c11/attachment-0001.html