Netflix Prize 2: What You Need To Know

At least one privacy expert is concerned that Netflix may be on the brink of a major data breach. As a follow-up to its hugely successful Netflix Prize — a conte

st to help improve Netflix’s software that suggests movies a user might like — the movie rental company will release anonymous information from 100 million Netflix users to allow researchers to try and predict their movie preferences based on their age, gender, and where they live, according to The New York Times. The problem is, there’s a concern that the information Netflix releases could make it very easy to identify specific individuals.

Here’s what you need to know:

What is the Netflix Prize 2?

Netflix says that it wants to use its next contest to design software that will help “customers early in their experience with Netflix, drawing on many more sources of data to try to find just the right movies.” The Times reported that Netflix wants to figure out which movies a Netflix user would like based on demographic information.

What User Data will be Released?

According to the Times , Netflix will release a database of 100 million anonymous users profiles that will include the following information:

• Age (not date of birth)
• Gender
• ZIP code
• Movie genre ratings (but not specific movie ratings)
• Previously rented movies

What are the Privacy Concerns?

Privacy expert Paul Ohm, an associate professor of law at the University of Colorado Law School, believes the information provided by Netflix for its latest contest could cause privacy breaches for many people using data mining techniques. Here’s why:

• Based on an individual’s age, gender, and ZIP code, you can narrow a person’s identity down to a few hundred possibilities
• In 2000, researcher Latanya Sweeney proved you could identify 87 percent of the American population by having three pieces of personal information: date of birth, gender, and ZIP code
• While steps were taken to provide anonymous data during the original Netflix Prize, researchers were still able to identify specific individuals.

Are Other Privacy-Watchers Worried?

So far, only Ohm has raised concerns about the Netflix Prize 2. Consumer advocates like Electronic Privacy Information Center and the Electronic Frontier Foundation have not released any statements, but that could change when Netflix releases more information about the contest.

What does Netflix say?

So far, Netflix has not responded to Ohm’s concerns, and it should be noted that information about Netflix’s plans have only been reported in The New York Times. Netflix has not made an announcement about specific information relating to the contest. I have contacted Netflix for comment, and will post their comments if they respond.

Can I Tell Netflix to Not Release my Data?

Netflix has yet to provide any concrete details about Netflix Prize 2, so it’s difficult to say whether the company will permit subscribers to opt out of this user database. However, according to Netflix’s privacy policy the company will not disclose your personal information to third parties without giving you the chance to “prevent your personal information from being shared.” The question is, does Netflix consider anonymous data like ZIP code, age, and gender “personal” information? We should learn more as Netflix releases more details about its next contest.