Illustration: Sarah Grillo/Axios

An exposé for New York Times Opinion out in December called "One Nation, Tracked," by Stuart A. Thompson and Charlie Warzel, walks readers through how they mined a data file of 50 billion location pings from the cellphones of 12 million Americans as they moved through several major cities, including D.C., New York, San Francisco and L.A.

Why it matters: Supposedly anonymous data isn't always all that anonymous.

  • The series image shows the pings from a single smartphone over several months in 2016 and 2017.
  • "Connecting those pings reveals a diary of the person’s life," the authors write.

"Watching dots move across a map sometimes revealed hints of faltering marriages, evidence of drug addiction, records of visits to psychological facilities."

"The data was provided ... by sources who asked to remain anonymous because they were not authorized to share it and could face severe penalties for doing so," The Times reports.

  • "The sources of the information said they had grown alarmed about how it might be abused and urgently wanted to inform the public and lawmakers."

Go deeper... Axios Deep Dive: Data Privacy

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Updated 29 mins ago - Politics & Policy

Coronavirus dashboard

Illustration: Annelise Capossela/Axios

  1. Global: Total confirmed cases as of 3 p.m. ET: 20,158,258 — Total deaths: 738,063 — Total recoveries: 12,388,686Map.
  2. U.S.: Total confirmed cases as of 3 p.m. ET: 5,116,791 — Total deaths: 164,137 — Total recoveries: 1,670,755 — Total tests: 62,513,174Map.
  3. States: Florida reports another daily record for deaths State testing plans fall short of demand.
  4. Axios-Ipsos poll: 1 in 2 has a personal connection to COVID-19.
  5. Business: Moderna reveals it may not hold patent rights for vaccine.
  6. 🏈 Sports: Big Ten scraps fall football season due to coronavirus.
36 mins ago - Sports

Big Ten postpones fall sports due to coronavirus

Photo: Joe Robbins/Getty Images

The Big Ten announced Tuesday that it has voted to postpone its 2020 fall sports season, including football, due to risks posed by the coronavirus pandemic, hoping instead to play in the spring.

Why it matters: The move from one of the most prominent conferences in college sports will almost certainly prompt other Power Five leagues to follow suit.

13 of Biden's former rivals to appear together at Democratic convention

Democratic presidential candidates at the primary debate in Charleston, SC. Photo: Win McNamee/Getty Images

In a show of unity at the Democratic National Convention, 13 of Joe Biden's former 2020 challengers will appear via video to talk about the party's vision for the country and how they'll work with Biden to get it done.

Why it matters: Coalescing around Biden and his eventual running mate will help Democrats head into the general election against President Trump with a united front — unlike what they did in 2016.