A technique to measure the privacy of a crucial data set.
Why it mattersIt is increasingly difficult for the US Census Bureau to keep the data it collects private. A technique called differential privacy could solve that problem, build trust, and also become a model for other countries.
Key playersUS Census Bureau, Apple, Facebook
AvailabilityIts use in the 2020 US Census will be the biggest-scale application yet.
In 2020, the US government has a big task: collect data on the country’s 330 million residents while keeping their identities private. The data is released in statistical tables that policymakers and academics analyze when writing legislation or conducting research. By law, the Census Bureau must make sure that it can’t lead back to any individuals.
But there are tricks to “de-anonymize” individuals, especially if the census data is combined with other public statistics.
So the Census Bureau injects inaccuracies, or “noise,” into the data. It might make some people younger and others older, or label some white people as black and vice versa, while keeping the totals of each age or ethnic group the same. The more noise you inject, the harder de-anonymization becomes.
Differential privacy is a mathematical technique that makes this process rigorous by measuring how much privacy increases when noise is added. The method is already used by Apple and Facebook to collect aggregate data without identifying particular users.
But too much noise can render the data useless. One analysis showed that a differentially private version of the 2010 Census included households that supposedly had 90 people.
If all goes well, the method will likely be used by other federal agencies. Countries like Canada and the UK are watching too.
How AI is reinventing what computers are
Three key ways artificial intelligence is changing what it means to compute.
These weird virtual creatures evolve their bodies to solve problems
They show how intelligence and body plans are closely linked—and could unlock AI for robots.
We reviewed three at-home covid tests. The results were mixed.
Over-the-counter coronavirus tests are finally available in the US. Some are more accurate and easier to use than others.
A horrifying new AI app swaps women into porn videos with a click
Deepfake researchers have long feared the day this would arrive.
Get the latest updates from
MIT Technology Review
Discover special offers, top stories, upcoming events, and more.