Hello everyone,
I was locking through CTPP 2006-2010 tables and was wondering which would be the best table to be used to calculate the number of vehicles (autos) physically located in households. Any suggestion would be appreciated.
Thanks,
Sulabh Aryal
Associate Planner
Richmond Regional Planning District Commission
9211 Forest Hill Avenue, Suite 200 Richmond, VA 23235
Phone: 804.323.2033 3 Fax: 804.323.2025
saryal(a)richmondregional.org<mailto:saryal@richmondregional.org> 3 www.richmondregional.org<http://www.richmondregional.org>
Hi! All,
I got an interesting question from our management.
They want to know if we can define a commuter by how many work trips this particular person make during certain period of time (a day, a week or a year).
The simple definition I found online to describe a commuter is "a person who travels some distance to work on a regular basis."
This brings up two basic questions:
1. How do we determine "some distance"?
2. How do we determine "regular basis"?
I could not find a clear definition regarding commuter in Commuting in America III though we talked about commuter population throughout the report.
Any insight on this would be greatly appreciated!
Juyin (roo-een) Chen, AICP
Travel Demand Modeling Coordinator
Virginia Department of Transportation
Transportation & Mobility Planning Division<http://maps.google.com/maps/place?cid=208056989819810995&gl=us&hl=en&cd=1&c…>
P +1-804-225-3564
F +1-804-225-4785
http://www.virginiadot.org/vtm/
All:
Some of you may find this of use: http://lexington.caliper.com/ctppmap
Peter
----------------------------------------------------------------
Peter H. Van Demark
Director of GIS Products and Training Phone: 617-527-4700
Caliper Corporation Fax: 617-527-5113
1172 Beacon Street, Suite 300 E-mail: peter(a)caliper.com
Newton MA 02461-9926 Web site: http://www.caliper.com
I am out of the office until 01/06/2014.
I will respond to your message when I return.
For any CTPP related questions, Please contact Haining Du by
Hdu(a)camsys.com
Note: This is an automated response to your message "ctpp-news Digest, Vol
118, Issue 1" sent on 12/5/2013 1:00:02 PM.
This is the only notification you will receive while this person is away.
Hi All,
As many of you know, we have been having a problem with intermittent availability of SHP file downloads. This appears to be fixed.
Penelope Z. Weinberger
CTPP Program Manager
AASHTO
202-624-3556
ctpp.transportation.org
Dear CTPP Users:
Are you wondering what are the differences between CTPP 2006-2010 and
Standard ACS products? Are you struggling Set A and Set B tables from the
recent released CTPP?
If so, please check our new FAQs on the FHWA website:
http://www.fhwa.dot.gov/planning/census_issues/ctpp/faq/index.cfm
As always, if you have any questions on the CTPP, feel free to contact me.
Liang Long
Cambridge Systematics, Inc.
4800 Hampden Lane
Suite 800
Bethesda, MD 20814
tel 301 347 0100
fax 301 347 0101
FHWA 202-366-6971
e-mail llong(a)camsys.com
www.camsys.com
From: Howard Slavin [mailto:howard@caliper.com]
Sent: Friday, November 15, 2013 11:32 AM
To: 'ctpp-news(a)chrispy.net'
Subject: RE: [CTPP] Adventures in large datasets
Thanks to Krishnan for the kind mention of TransCAD. I wanted to let everyone know that Caliper is now distributing the ctpp flow data in matrix form for TransCAD users. While the data have been provided at the Transportation Analysis Zone level, only the Census tract to Census tract flow data are complete, and these are the data that Caliper is now providing to TransCAD users in the United States. The flow data are provided in the form of two TransCAD matrices that provide the estimated flows between all of the Census tracts in the U.S. and that distinguish estimated work trip flows with two different breakdowns by means of transportation and margins of error. The dimensions of these matrices are roughly 70,000 by 70,000, but remarkably they compress to only 1.5 GB or less and so are downloadable. With TransCAD, it is easy for users to subset the matrices to cover any geographic subarea of interest. These files can be downloaded by users at http://www.caliper.com/Press/census-ctpp-worker-flow-data-download.htm
We expect to make the TAZ to TAZ flow data available as soon as it is corrected by the Census Bureau.
Howard
From: ctpp-news-bounces(a)chrispy.net<mailto:ctpp-news-bounces@chrispy.net> [mailto:ctpp-news-bounces@chrispy.net] On Behalf Of Krishnan Viswanathan
Sent: Thursday, November 14, 2013 9:59 PM
To: ctpp-news(a)chrispy.net<mailto:ctpp-news@chrispy.net>
Subject: Re: [CTPP] Adventures in large datasets
Mara
Besides SQL server I have the following suggestions:
1) the ff package in R ( http://www.bnosac.be/index.php/blog/22-if-you-are-into-large-data-and-work-…)
2) HDF5 seems like a decent option though I have not used it. Link to rhdf5 ( http://bioconductor.org/packages/release/bioc/html/rhdf5.html). Also, SFCTA has some code for getting data into and out of HDF5 ( https://github.com/sfcta/TAutils/tree/master/hdf5)
3) I have found TransCAD to be efficient in processing large datasets.
Hope this helps.
Krishnan
I downloaded the Maryland state raw data (the whole enchilada) that Penelope was good enough to provide me. It came with documentation that clearly explains what needs to be done but I am being hampered by the sheer size of the dataset. It's 10 GB and that's without going into joining tables, transposing them to meet my needs, etc. Even breaking the parts into different databases it can't be handled in Access. I can fit Part 1 into an ESRI geodatabase but I don't have the flexibility in linking tables that Access has.
Does anyone have any suggestions for dealing with large databases? SQL server is one option. Are there others?
Mara Kaminowitz, GISP
GIS Coordinator
.........................................................................
Baltimore Metropolitan Council
Offices @ McHenry Row
1500 Whetstone Way
Suite 300
Baltimore, MD 21230
410-732-0500 ext. 1030<tel:410-732-0500%20ext.%201030>
mkaminowitz(a)baltometro.org<mailto:mkaminowitz@baltometro.org>
www.baltometro.org
<http://www.baltometro.org/>
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