Study: It's Not Hard to Connect Anonymous Data to Specific Individuals

People have had to take it on faith that data anoymization was adequate to the task of protecting privacy of individuals. Recent research suggests such faith was misplaced.

1 minute read

July 27, 2019, 1:00 PM PDT

By James Brasuell @CasualBrasuell


United States from Space

MarcelClemens / Shutterstock

Researchers from Université catholique de Louvain in Belgium and Imperial College London have debunked the notion that data can be anonymized as promised by tech companies.

"Using machine learning, the researchers developed a system to estimate the likelihood that a specific person could be re-identified from an anonymized data set containing demographic characteristics," according to an article by Nick Wells and Leslie Picker. "The researchers’ model suggests that over 99% of Americans could be correctly re-identified from any dataset using 15 demographic attributes, including age, gender and marital status."

The research was published in the journal Nature Communications, and as part of the effort, the researchers, "published an online tool to help people understand how likely it is for them to be re-identified, based on just three common demographic characteristics: gender, birth date and ZIP code."

A quote from Yves-Alexandre de Montjoye, one of the researchers, sums up the problem inherent to the study's findings, and the implications for fields like planning, where big data has promised large benefits to society: "The goal of anonymization is so we can use data to benefit society," said Montjoye. "This is extremely important but should not and does not have to happen at the expense of people’s privacy."

Tuesday, July 23, 2019 in CNBC

portrait of professional woman

I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching. Mary G., Urban Planner

I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching.

Mary G., Urban Planner

Get top-rated, practical training

Wastewater pouring out from a pipe.

Alabama: Trump Terminates Settlements for Black Communities Harmed By Raw Sewage

Trump deemed the landmark civil rights agreement “illegal DEI and environmental justice policy.”

April 13, 2025 - Inside Climate News

High-rise apartment buildings in Waikiki, Hawaii with steep green mountains in background.

Study: Maui’s Plan to Convert Vacation Rentals to Long-Term Housing Could Cause Nearly $1 Billion Economic Loss

The plan would reduce visitor accommodation by 25% resulting in 1,900 jobs lost.

April 6, 2025 - Honolulu Civil Beat

Logo for Planetizen Federal Action Tracker with black and white image of U.S. Capitol with water ripple overlay.

Planetizen Federal Action Tracker

A weekly monitor of how Trump’s orders and actions are impacting planners and planning in America.

April 10, 2025 - Diana Ionescu

A line of white wind turbines surrounded by wheat and soybean fields with a cloudy blue sky in the background.

Wind Energy on the Rise Despite Federal Policy Reversal

The Trump administration is revoking federal support for renewable energy, but demand for new projects continues unabated.

April 15 - Fast Company

Red and white Caltrain train.

Passengers Flock to Caltrain After Electrification

The new electric trains are running faster and more reliably, leading to strong ridership growth on the Bay Area rail system.

April 15 - Office of Governor Gavin Newsom

View up at brick Catholic church towers and modern high-rise buildings.

Texas Churches Rally Behind ‘Yes in God’s Back Yard’ Legislation

Religious leaders want the state to reduce zoning regulations to streamline leasing church-owned land to housing developers.

April 15 - NBC Dallas