These days Mr. Cohen thinks a lot about how to do history in an era of abundant digital materials. In a recent project, he examined whether one scholar’s famous assertions about Victorian thought, made on the basis of close reading of classic literature, held up against an analysis of Google’s collection of over a million Victorian books.

Critics view such “distant reading” as superficial. Others, like the historian Zachary Schrag, grouse that Mr. Cohen’s publishing experiments risk destroying what’s valuable about traditional scholarly communication, like good editing that improves manuscripts and filters out the “crud.”

Mr. Cohen pushes back against the pushback. For example, he views big data-versus-close-reading as a false fight; better, he says, to adopt a hybrid approach that draws on both. That response reflects Mr. Cohen himself: a smart mix of old and new.

Sarah Palin was criticized for allegedly conducing public business on a private, Yahoo! account. Could Cronon face similar challenges? And how often are Bill Cronon and Sarah Palin mentioned in the same paragraph?

(h/t Dan Cohen)

For more along these lines, see

• William Pannapacker, “Overeducated, Underemployed: How to Fix Humanities Grad School, Slate, 27 July 2011. Also, responses.
• William Deresiewicz, “Faulty Towers: The Crisis in Higher Education,” The Nation, 4 May 2011. With letters.
• “The Disposable Academic: Why doing a PhD is Often a Waste of Time,” The Economist, 16 December 2010. With comments.

Just as Jewish tradition advises that people wishing to convert to Judaism be discouraged three times, so aspiring history PhDs should probably have to read three of these, but not more.

The original Metro system was estimated to cost $2.5 billion in 1969, but it came in at $3.8 billion — not counting inflation, according to Zachary M. Schrag, associate professor of history at George Mason University and author of “The Great Society Subway,” a history of Metro.

“It would be somewhat surprising for a major rail transit project to be completed on budget,” Schrag said. “Most major projects of any kind go over budget, that includes road projects, weapons systems, space programs, stadiums.”

Typically, overruns hit because it is hard to predict the cost of such expenses as materials and the relocation of utilities in a construction area, Schrag said. “It is kind of a vicious spiral where people low-ball the estimates to get their project approved,” he said.

“I don’t have much confidence in these textbooks,” said Zachary Schrag, a history professor at George Mason University who enumerated his concerns in a four-page memo to the state.