Everyone knows that adjuncts and graduate assistants do a lot of the teaching these days, right? Well, maybe not everyone.

The American Federation of Teachers on Wednesday posted a blog item asking how it is, given those well documented trends, that magazine rankings give parents the sense that most of the teaching at large universities is done by full-time faculty members. "The majority of top colleges report well over 80 percent of their faculty are full-time and a large number report that well over 90 percent of their faculty are full-time. University of Nebraska-Lincoln even reports that 100 percent of its faculty are full-time," the blog says of institutions in the U.S. News & World Report rankings, a small part of which are based on the percentage of faculty who are full time. "Amazing!"

Further, the blog goes on to note that AFT data suggest that at Nebraska, only 79 percent of the faculty members are full time. How could the university's claim (and many others universities' claims to be almost entirely full time in faculty members) be accurate? the AFT asked.

Inside Higher Ed posed the question to the University of Nebraska and to U.S. News and found that the two have very different interpretations of how to count faculty members -- and that the magazine will let stand Nebraska's decision to exclude all of its adjuncts and claim a faculty make-up it does not in fact have.

Kelly H. Bartling, a spokeswoman for the university, said Nebraska interpreted the U.S. News question on the percentage of full-time faculty to cover only those faculty who are tenured or on the tenure track, and not to include anyone else. She said that the university gave the magazine figures that were "exactly what they've been asking for," and that she believed other universities had similar interpretations, given their high percentages of full-time faculty members. (Given that most research universities don't have many part-time tenure-track or tenured slots, an interpretation like Nebraska's would produce many very high percentages, which is the case in the rankings.)

Robert Morse, who leads the college rankings operation at U.S. News, forwarded a definition sent to colleges showing how to count faculty members. A chart details various groups to include or exclude and, following that, adjuncts are clearly stated as a group that should count.

Asked if the magazine should redo its figures for Nebraska and check others with very high percentages, Morse noted in an e-mail that the share of the total score based on full-time faculty members is small, adding: "We will not change the rankings or go back to each school. The definition is very clear. If Nebraska has adjuncts and they are not reporting them, they are not following the definition -- no matter what they say."

He did note that Nebraska actually didn't report a pure 100 percent figure and that it took rounding to get there -- the university told the magazine in its forms that 11 of its 1,081 faculty members were not full time.

Of course the adjuncts are only part of the teaching work force that is missing from the magazine's rankings. Morse said that graduate student instructors -- who have extensive teaching duties at most research universities -- do not count. As the AFT blog noted: "Another look at Nebraska's data shows that they reported having 1,852 graduate assistants. That is nearly the same number of graduate assistants as all faculty at the University of Nebraska, and we know that graduate employees at research institutions such as Nebraska are carrying more and more of the instructional workload."

In an interview, Lawrence N. Gold, director of higher education at the AFT, said he was bothered by the unwillingness of U.S. News to fix the error and to make sure that the faculty figures are all correct -- and that the union would formally ask the magazine to reconsider. The concern comes at a time when the union has launched a campaign -- called "Just Ask" -- that encourages parents and prospective students to ask colleges about the percentage of courses taught by tenure-track faculty members.

"It seems to me that if U.S. News is putting forth these rankings as an accurate guide for families, if institutions don't properly portray the population of adjuncts, the rankings aren't portraying the situation," Gold said. "By saying that they don't care enough to correct it, they are not putting out accurate information."

Even if the share of the rankings formula devoted to this category is small, Gold noted that the data on faculty make-up are published in each institution's full profile. He said it should be correct, for the same reason the union is urging parents to ask about the issue.

"We think it's awfully important for parents and students to know who is doing the teaching and how those people are treated," he said. "Teachers are the most important factor in any student's success. The overuse and exploitation of contingent faculty is something they should be aware of and take into consideration."