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Answers (2)

- herbuk
- Contributions:2
You might consider putting out a general announcement. For those of us tracking property, the significant change was very disturbing. User submitted facts, I hope there is a validation process otherwise the integrity of your estimates was just compromised.

- Rachel Rosen, "RachelRosen"
- Contributions:1487
Hi Herbuck,
Thanks for using Zillow. We recently changed our algorithm to include user submitted facts on more than 28 Million homes which we have gathered over the years. The new algorithm was dated back to 2006. This is why you see the change in history.
You can learn more through these links:
http://www.zillow.com/wikipages/Zestimate-Improvements/
http://www.zillow.com/blog/research/2011/06/14/upgrading-the-zestimate/
http://www.zillow.com/blog/2011-06-14/zillow-expands-and-improves-database-of-homes/
Thanks for using Zillow. We recently changed our algorithm to include user submitted facts on more than 28 Million homes which we have gathered over the years. The new algorithm was dated back to 2006. This is why you see the change in history.
You can learn more through these links:
http://www.zillow.com/wikipages/Zestimate-Improvements/
http://www.zillow.com/blog/research/2011/06/14/upgrading-the-zestimate/
http://www.zillow.com/blog/2011-06-14/zillow-expands-and-improves-database-of-homes/
50% increase in Zillow estiame in 1 week
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