"There is no standard format, which is very frustrating," says Humphries. "We've tried and tried to push the government to come up with standard formats, but from [each individual] county's perspective, there's no reason to do it. So it's up to us to figure out 3,000 different ways to ingest data and make sense of it."
Complaints about the lack of standard protocols and formats are common among users of open data.
"Data quality has always been and will continue to be a very important consideration," says Chui. "It's clear that one needs to understand the provenance of the data, the accuracy of the data, how often it's updated, its reliability -- these will continue to be important problems to tackle."
So far, Zillow's plan of attack using "sophisticated big data engineering" is working. In fact, a new set of algorithms has helped improve Zillow's median margin of error from 14% to 8%. And for 60% of all sales that occur, Zillow's estimated sales price is within 10% of the actual figure.
Should You Share?
In early February, the National Institutes of Health, 10 drug companies and several nonprofit organizations made an unprecedented deal: They agreed to share the data and analyses they generate in the race to develop drugs to treat Alzheimer's disease, Type 2 diabetes, rheumatoid arthritis and lupus. The $230 million project, which will last three to five years, marks a clear departure from a secretive way of conducting research to one that involves swapping scientists, blood samples and data in the name of scientific discovery.
But while sharing data can be a win-win situation, the decision to open your treasure troves shouldn't be made lightly. "The potential benefits, and risks, are multiplied when data is shared," says Michael Chui, a partner at the McKinsey Global Institute.
So how do you know whether it's wise to share your data? First, you must ask whether your IT department actually owns the data it collects and manages. Healthcare and financial data, for example, will need to be anonymized before it can be monetized. And in many cases, companies must negotiate with customers to secure the right to use their data long before the number-crunching begins.
You should also determine whether sharing data could leave you vulnerable to legal action by others who rely on your data to run their businesses. Financial and weather data, for example, can change from moment to moment. Offering such data to other companies to use as the basis for making decisions can be risky. Just ask Weather Company CIO Bryson Koehler. "We are publicly predicting the future every minute," he says. "And we're on public display as to whether or not we are right or wrong."
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