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When you type in a home s street address to obtain an online上海千花社区 valuation from the two biggest players in the field Zillow s Zestimate or Redfin s Estimate tools how good is what you get?
Bot上海千花网 h are used by millions of home shoppers, owners, realty agents, anyone curious about what a house in their neighborhood might be worth. Both also have been criticized for estimates that are off the mark; some homeowners have actually sued Zillow over their Zestimates, though unsuccessfully. Zillow s own CEO, Spencer Rascoff, famously sold his Seattle home for 40 percent below its Zestimate.
Accuracy matters a lot in this arena because many buyers and sellers use the online estimates to price their homes or make purchase offers, literally handing sellers or buyers the estimates as part of their bargaining strategy. This is despite both companies warnings that these are not appraisals, only algorithm-based computer estimates. They are starting points, not holy writ.
So which company s estimate is the more accurate? For two years, Redfin has claimed that it produces estimates that are superior, based on the results of an inde新上海贵族宝贝论坛 pendent study. When it values homes that are on the market, Redfin says its median national error rate is just 1.77 percent. That is, the selling price, compared with the estimate, is within that margin of error half the time. On houses that are not for sale, Redfin s median error rate is 6.66 percent. Redfin has a total of 74.4 million properties in its valuation database 1.3 millio爱上海同城手机版 n on the market and listed for sale, 73.1 million off the market.
But now it looks like bragging rights for accuracy could be shifting to Zillow. Following an international contest involving teams of data scientists, Zillow announced that its median error rate on valuations of the 110 million U.S. homes in its database will soon drop to 4.0 percent or even below, from the current 4.5 percent. Zillow does not provide a breakout that distinguishes between its error rates for homes already listed on the market and off-market homes, so there is no direct comparison to Redfin s claimed 1.77 percent figure for listed houses. But the overwhelming majority of homes in Zillow s 110 million-property database are off-market, which are more challenging to value because there s usually less detailed information available on them. Note the difference in Redfin s 1.77 percent 阿爱上海同城 error rate for listed homes versus its 6.66 percent rate for off-market homes. Given this, Zillow s claim that it will have a 4 percent composite error rate on 110 million homes the vast majority of them off-market looks better.
An error rate of 4 percent or less would put Zillow close to a standard that many appraisers consider passable for their own work. Ryan Lundquist, an appraiser in the Sacramento, California, area, told me that for many colleagues, a 4 percent median error rate would be a fairly acceptable range.
Pat Turner, an appraiser i[……]