Many enterprises are still struggling with how to get value out of their own data.But some companies, like online real estate marketplace Zillow, have made products  entirely out of data from outside their organization. In Zillow's case, the entire business is built on real estate data provided by public information, private subscription, and by customers themselves. The company, which launched in 2005 and debuted online in 2006, posted 2012 net income of $5.9 million on $116.9 million in revenue, a revenue hike of 77 percent.Stan Humphries, Zillow's chief economist, said the current version of the Zestimate, Zillow's home valuation estimate, is based on 3.2 terabytes of data. None of that data is created by Zillow itself; it's value is created by Humphries' algorithm and the user experience on Zillow's website.In this interview with Data Informed staff writer Ian B. Murphy, Humphries discusses the immense value of having customers update and enrich Zillow's dataset, the need for transparency and open dialogue about Zillow's home valuation models, and the difference between creating a data product to be used by businesses, and one for consumers. (Podcast length: 17:48.)Email Staff Writer Ian B. Murphy at ian.murphy@wispubs.com. Check out other Big Data podcasts from Data Informed. Related articles on Data Informed:NHC Analysts' Predictive Models Improve Hurricane Season ForecastsMcKinsey Report: Big Data at Center of Disruptive TechnologiesData Quality Key to Future Analytics Value