David Cay Johnston has written a column explaining how he misread News Corp.'s tax filings, wrongly concluding that the company had received $4.6 billion in tax refunds. That's how much the company paid. "For the first time in my 45-year-old career I am writing a skinback. That is what journalists call a retraction of the premise of a piece, as in peeling back your skin and feeling the pain." The error, he explains, stemmed from the company's change in reporting its tax payments as positive number to negative numbers. Reuters issued an advisory on the first column Wednesday afternoon and deleted it later that day.

The error, writes Craig Silverman on Regret the Error, is "a reminder that any of us can make mistakes. ... But his response is also a reminder that it matters what you do after you discover your error." Points against Reuters, he adds, for simply deleting the first post. That URL now goes to en error page. "Reuters should redirect that URL to the corrective column."

Johnston appeared on NPR's "Morning Edition" Wednesday morning to talk about his conclusions; a correction has been posted to that story. He came on again Thursday morning to explain his mistake. NPR Ombudsman Edward Schumacher-Matos called Johnston's column "a model apology."

Related: Why journalists make mistakes & what we can do about them