Working With My Zestimator
Since much of the feedback so far has been in the area of data and Zestimate accuracy, we thought it couldn’t hurt to give a little overview of the My Zestimator tool. Lloyd already discussed it a bit in his earlier post, but here’s more detail for those of you who might be encountering inaccurate data on a house, want to refine the Zestimate with some additions or renovations to a home, or need some tips on using My Zestimator.
When we set out to create Zestimates, we quickly realized that we could only go so far in assigning a value to every home in the U.S. from the cramped confines of our current offices in Seattle. It was obvious that people would have a vast amount of knowledge essential to truly understanding home values in their own neighborhoods that we simply don’t know about here. It was from this realization that the idea for My Zestimator was born. My Zestimator is an interactive tool that you access by clicking on the “Refine value of home with My Zestimator” link on the details page for a given home. (The link is just below the Zestimate figure. After you go through the four steps of My Zestimator, you will get a summary page similar to the attached screenshot). By using this tool, a user can come up a more accurate Zestimate by updating four specific areas important to the valuation process:
• First, if you see outdated or just plain wrong data on a home, you can correct the basic facts. For example, say the Home Facts indicate that you’ve got two bedrooms, but you really have three. In the first step of My Zestimator, update the bedroom count from 2 to 3. Remember to change the square footage accordingly.
• In Step 2, you can add in details about home improvements that have been made to the house. Fill in details about any updates you may have made, such as a remodel to a kitchen or a deck addition.
• In Step 3, we give you the opportunity to add other special attributes about the home which you think either add to, or subtract from the value of the home. For example, here you might add some value for a view of the mountains or subtract value for being next to a landfill (stay tuned for more thoughts in the future about whether landfills are really that bad for resale prices on surrounding homes!).
• Lastly, in Step 4, we come to what I believe is probably the most powerful aspect of My Zestimator – choosing comparable transactions. Here, you can tell us about other nearby recently-sold homes that you believe are great comps to the current one. From amongst a list of up to 50 comparable homes around a given house, pick up to 10 homes that you feel are really very similar in key ways to the current house.
Right now, My Zestimator works best for users who complete all four steps of the process. We’ve gotten a lot of feedback from folks who’ve completed Step 1 (Edit Home Facts), received curious changes in the home value at this stage, and bailed out without completing the other three stages. The reward will be greater if you hang in to the end since the physical data on the home is best evaluated in the context of homes that you’ve indicated are good comparables for a property.
In some cases, you might still find that My Zestimator is quite sensitive to small changes in inputs. This sensitivity has to do with the particular characteristics of data around your home on that particular day (since we’re adding new data all the time). We’re working very hard to make this tool even more robust and think we’ll have some good results to share with our users in the coming months. We’ve not seen many other tools quite like this one that works on the fly, so we think it’s a cool and very promising tool. The specific feedback that we are currently getting is very helpful in our efforts at improving My Zestimator and I’d like to encourage folks to continue telling us what’s working and what’s not. And we can’t wait to show you what we’re cooking up next on this front!
Dr. Stan Humphries is a real estate economist and real estate expert for Zillow. Stan is in charge of the data and analytics team at Zillow, which develops housing market data for most major metropolitan statistical areas in the U.S., and provides economic research for current real estate market conditions. He helped create the algorithms for the popular Zestimate® home value and the Zillow Home Value Index (ZHVI).
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