Chris Giles Challenges Thomas Piketty’s Data Analysis


Chris Giles of the Financial Times has been diving into the source data that underlies Thomas Piketty’s Capital in the 21st Century, and he says he’s found some problems. The details are here. Piketty’s response is here.

Is Giles right? Experts will have to weigh in on this. But Giles’ objections are mostly to the data regarding increases in wealth inequality over the past few decades, and the funny thing is that even Piketty never claims that this has changed dramatically. The end result of Giles’ re-analysis of Piketty’s data is on the right, with Piketty in blue and Giles in red. As you can see, Piketty estimates a very small increase since 1970.

Now, if Giles is right, and there’s been no increase at all, that’s important. But it’s still a surprisingly small correction. The fundamental problem here is that the difficulties of measuring wealth are profound enough that it’s always going to be possible to deploy different statistical treatments to come to slightly different conclusions. There’s just too much noise in the data.

In any case, I’m not taking any sides on this. The data analysis is too arcane for a layman to assess. But it’s worth keeping an eye on.

THE BIG QUESTION...

as we head into 2020 is whether politics and media will be a billionaires’ game, or a playing field where the rest of us have a shot. That's what Mother Jones CEO Monika Bauerlein tackles in her annual December column—"Billionaires Are Not the Answer"—about the state of journalism and our plans for the year ahead.

We can't afford to let independent reporting depend on the goodwill of the superrich: Please help Mother Jones build an alternative to oligarchy that is funded by and answerable to its readers. Please join us with a tax-deductible, year-end donation so we can keep going after the big stories without fear, favor, or false equivalency.

THE BIG QUESTION...

as we head into 2020 is whether politics and media will be a billionaires’ game, or a playing field where the rest of us have a shot.

Please read our annual column about the state of journalism and Mother Jones' plans for the year ahead, and help us build an alternative to oligarchy by supporting our people-powered journalism with a year-end gift today.

We Recommend

Latest

Sign up for our newsletters

Subscribe and we'll send Mother Jones straight to your inbox.

Get our award-winning magazine

Save big on a full year of investigations, ideas, and insights.

Subscribe

Support our journalism

Help Mother Jones' reporters dig deep with a tax-deductible donation.

Donate

We have a new comment system! We are now using Coral, from Vox Media, for comments on all new articles. We'd love your feedback.