Those familiar with the powerhouse real estate listing site Zillow will likely recall that it burst on the scene in 2006 with an irresistible new offering: a free online estimate of the value of every house in the United States. Zillow calls them Zestimates. The site crashed continuously from too much traffic when it first launched, and Zillow now gets a stunning 195 million unique visitors monthly, all with virtually no advertising. Credit the Zestimates for this.
As you would expect, Zestimates are derived algorithmically, using a combination of public domain and recent sales data. The algorithm selects recent sales of similar comparable nearby houses to compute estimated value.
As you would also expect, professional appraisers hate Zestimates. They believe that they produce better valuation estimates because they hand select the comparable nearby homes and are thus more accurate. However, with the goal of consistent appraisals, the hand selection process that appraisers use is so prescribed and formulaic that it operates much like an algorithm does. At this level, you could argue that appraisers have little advantage over the computed Zestimate.
However, one area in which appraisers have a distinct advantage is that they are able to assess the condition and interiors of the properties they are appraising. They visually inspect the home and can use interior photos of comparable homes that have recently sold to refine their estimates.
Not to be outdone, Zillow is employing artificial intelligence to create what it calls “computer vision.” Using interior and exterior photos of millions of recently sold homes, Zillow now assesses such things as curb appeal, construction quality and even landscape; quantifies what it finds; and factors that information into its valuation algorithm. When it has interior photos of a house, it scans for such things as granite countertops, upgraded bathrooms and even how much natural light the house enjoys, and incorporates this information into its algorithm as well.
With this advance, appraisers look very much like their competitive advantage is owning “the last mile,” because they are the feet on the street that actually visit the house being appraised. But you can see where things are heading: as companies like Zillow refine their technology, the day may well come that an appraisal is performed by the homeowner uploading interior pictures of her house, and perhaps confirming public record data, such as number of rooms in the house.
There are many market verticals where automated inspection and interpretation of visual data can be used. While the technology is in its infancy, its power is undeniable, so it’s not too early to think about possible ways it might enhance your data products.