There have been a lot of thoughtful comments and good suggestions on this thread. Here a couple more to bear in mind.
Too radical a change to the Means of Transportation question could lead to a break in series, where we would have to wait for five years before getting access to small area data again, which is likely to be 2029 based on the schedule Clara
laid out. This could affect ongoing planning operations throughout the US and could upset the timing of future updates to the CTPP data set. This consideration points to endorsing an incremental change that meets our needs for the near future and allows
the ACS to continue to publish data in way that we can continue to have access to small area data. If this scenario seems unlikely, just this situation appears to have happened to the ACS language question this past year.
The language question situation leads to the other caution I want to point out. My understanding is that any change in the wording of ACS questions triggers a review of data privacy implications. If a modified question creates a large
quantity of small number values there is a danger that the change would trigger enhanced privacy protections, and we could end up with less data rather than more. An example of how this might happen would be if ridehailing was split into a separate option.
While those of us in metro areas where Uber and Lyft both operate might find this an unlikely scenario, market penetration by ridehailing companies is probably very uneven. Adding a separate ridehailing option is likely to produce a lot of small area values
in the low numbers. To protect the identity of ridehailing users in outlying suburban and rural areas we could lose access to data for urban users. As an example, in the case of languages we have gone from having detailed small area data available for 41
language groups (Table B16001) to only having 13 available (C16001). Those may not matter too much in many places but it matters a great deal in ethnically diverse urban centers.
Cliff Cook
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From: ctpp-news [mailto:ctpp-news-bounces@chrispy.net]
On Behalf Of Reschovsky, Clara (OST)
Sent: Tuesday, July 17, 2018 4:02 PM
To: ctpp-news@chrispy.net
Subject: [CTPP] Means of Transportation changes
CTPP community,
As some of you may remember, or not since it has been a while, the Census Bureau is changing the Means of Transportation question categories for public transit options in 2019. This change is the result of a content test conducted in 2016
by the Census Bureau. Here is the current question as it appears on the form and the new version which will be implemented in January 2019.
2018 Version:
2019 Version:
So now that you see that change can happen even if it takes a long time, we have a new opportunity!
Currently the Census Bureau is planning another Content Test for the American Community Survey. US DOT has the opportunity to propose a new change to the journey-to-work questions. At this point, we are thinking of proposing the addition
of ride-hailing services to the Taxicab category in the Means of Transportation question. The initially proposed change is from ‘Taxicab’ to ‘Taxi or ride-hailing services’.
The Content Test will be conducted in 2021 and any changes that are deemed successful will be implemented in 2024. At this point, it is hard to know how technology will change in the next six years and how that will affect the ACS data,
but this is a known emerging mode. However, we need to act now to have any changes considered.
I am interested in hearing your input and hopefully support on this proposed change, but I must caution you on a few details. We cannot add a specific company name (such as Uber and Lyft) to the options. We also have very limited space
available on the form, however, in consultation with the form design experts at the Census Bureau we can change Taxicab to be a two line choice like ‘Long-distance train or commuter rail’ on the 2019 form. I know that some of you would really like to see
ride-hailing as a separate option and that is unlikely to be successful because of space of the form. If you have any thoughts on this topic, please let me know by July 31st, and for everybody, look forward to the new data detail on Means of Transportation
from Census!
Clara
Clara Reschovsky
Survey Statistician
Office of Survey Programs
Bureau of Transportation Statistics
US Department of Transporation
(202) 366-2857