Does anyone know if they looked at how well the model they developed predicted
demographics in low car ownership areas like New York City, where less then half of the
households have cars? It did not seem like they used any data from the NY area. In built
up, high density areas, many of the cars are in structured parking or people do not own
cars. On-Street cars may not represent who is living in the area. Same for high density
areas in other cities.
From: ctpp-news [mailto:ctpp-news-bounces@chrispy.net] On Behalf Of Krishnan Viswanathan
Sent: Friday, December 01, 2017 10:15 AM
To: Ed Christopher
Cc: ctpp-news(a)chrispy.net
Subject: Re: [CTPP] The Washington Post: Scientists can now figure out detailed, accurate
neighborhood demographics using Google Street View photos
Totally agree with you Ed. I think the Washington Post headline is a dose of hyperbole. I
have a question about spurious correlations and as far as I know the ACS does not ask what
type of vehicle is there in the household so this paragraph in their paper gave me
pause:
Using ACS and presidential election voting data for regions in our training set, we train
a logistic regression model to estimate race and education levels and a ridge regression
model to estimate income and voter preferences on the basis of the collection of vehicles
seen in a region. This simple linear model is sufficient to identify positive and negative
associations between the presence of specific vehicles (such as Hondas) and particular
demographics (i.e., the percentage of Asians) or voter preferences (i.e., Democrat).
On Fri, Dec 1, 2017 at 9:38 AM, Ed Christopher
<edc@berwyned.com<mailto:edc@berwyned.com>> wrote:
Interesting stuff Krishnan--
If their basic assumption were true, that vehicle ownership somehow translates into
demographics (ie voter behavior), then why not just cut Google out and process vehicle
registration files. It seems to me that would be a lot easier and cheaper. Then again you
have to buy the basic assumption. Also, if you look at precinct by precinct voter behavior
two things will surprise you. First, precincts are not all one color (red or blue) in most
places and the number of people who do vote are very small when considering the total
population. While I found this work interesting I would not be out their trying to
oversell what its capabilities are without a whole lot more work and research. As I see it
we have a very long way to go before we have something that is a kin to the ACS and all
its by-products.
On 11/30/2017 8:39 PM, Krishnan Viswanathan wrote:
This will interest people in this group and also foster discussion about the methods used.
The article itself has a link to the paper.
Scientists can now figure out detailed, accurate neighborhood demographics using Google
Street View photos
http://wapo.st/2AnuP9L
Krishnan Viswanathan
5628 Burnside Circle
<https://maps.google.com/?q=5628+Burnside+Circle+%0D+Tallahassee+FL+32312&entry=gmail&source=g>
Tallahassee FL 32312
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Ed Christopher
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Krishnan Viswanathan
5628 Burnside Circle
Tallahassee FL 32312