FAQ
What is Trulia Hindsight?
Trulia Hindsight is an animated map of residential properties in the USA that allows you to see when neighborhoods and cities were built. Slider controls allow you to view a specific time range or drag through the timeline. You can also search for specific properties, areas or cities through the search box.
What is the data and where does it come from?
The information comes mainly from property assessor records that have been aggregated, consolidated, cleaned up and processed so they can be used on a map. Assessor records and prior sale history are public records information dating back five years, as recorded for tax assessment purposes. Every property shown also has a corresponding page on Trulia where you can view prior sale history and compare with nearby and similar properties.
Why are some areas empty?
The data is collected locally and not all areas report in the same way. Sometimes there is a delay in gathering the data and occasionally things can go missing. The data only shows residential properties so in heavily commercial or industrial areas the points will be sparse even though the land is clearly developed. Lastly, some places do not keep records in the same way, for example military compounds or other government land.
How recent is the information?
The information is updated on a weekly basis as new information becomes available. The updates from each area differ, however, and in some cases may be amendments to items that are several months out of date. Check the pages for individual properties at Trulia for an accurate date.
Is the data available for other projects?
A large amount of data is already available in the Trulia API, but the data that drives the Hindsight visualizations cannot be accessed there at this time. Please get in touch with Trulia with details of your proposed application if you are interested in accessing the database.
What do the colors mean?
The oldest property viewed is shown in yellow, and the newest is shown in purple. Everything else is colored in between. This means you can watch the development of a city as it spreads from the oldest properties in yellow through green, to the newest properties in blue and purple.
The same colors are used for properties no matter where you’re looking at - this means you can easily compare properties within a view, but sadly it means it is not possible to compare the colors between two different places.
If your question isn’t answered here, please leave a comment below:
July 27th, 2007 at 3:49 pm
can I use your spatiotemporal engine to visualize my own data?
July 27th, 2007 at 5:19 pm
atomek: it’s not set up that way at the moment.
However, please feel free to contact Trulia or Stamen about potential uses of our software if you have a specific need in mind.
June 9th, 2008 at 12:15 pm
Where can I get the value of a specific address in Los Angeles for the year 1997?
June 17th, 2008 at 1:21 pm
Bryan: I’ve passed on your request to the Trulia team, and I’ll get back to you soon if they can help.
June 22nd, 2008 at 8:42 pm
Is there any way to overlay property history of residences that no longer exist, e.g. all of the homes sacrificed to “Richest Hill on Earth” ?
Thanks
Tony
June 22nd, 2008 at 9:06 pm
Tony, the data shown comes from current property assessments. Sadly the database we’re visualizing doesn’t contain that kind of historical data. It’s a great idea though!