Columbia University will not participate in the next U.S. News & World Report rankings of colleges across the country, after a Columbia math professor questioned the accuracy of the data that secured its No. 2 spot in the influential rankings, the university announced on Thursday night.
The deadline to submit data for the rankings is Friday, and a university spokesman said officials needed more time to analyze the data and address the criticisms raised by the professor, Michael Thaddeus.
In a 21-page stinging critique Dr. Thaddeus posted on his website in February, he not only challenged the data behind the rating but added fuel to the debate over whether college rankings — used by millions of prospective college students and their parents — are valuable or even accurate.
“Columbia leaders take these questions seriously, and we immediately embarked on a review of our data collection and submissions process,” Columbia’s provost, Mary C. Boyce, said in the announcement.
At the time, Columbia stood by its data, but Dr. Boyce said the university was “now closely reviewing our processes in light of the questions raised.”
“The ongoing review is a matter of integrity,” she continued. “We will take no shortcuts in getting it right.”
A spokesman for Columbia, Ben Chang, said he did not want to speculate about when Columbia would again participate in the rankings.
For an Ivy League school like Columbia to withdraw from the rankings, even temporarily, is a blow to their reputation and could spur other universities to reconsider their participation as well. Many college presidents complain that the rankings force them to emphasize statistics that oversimplify what it takes to find a good match between a student and a school.
Dr. Thaddeus said on Thursday night that the move raised a host of questions that Columbia had not yet answered.
“Is the university expressing its disapproval of the U.S. News rankings themselves?” he wrote in an email. “Will it withdraw in future years as well? Why can’t the work be completed? What was it about the questions I raised that, apparently, derailed the process?”
The university had not made “any substantive responses to the concrete issues I brought up,” he added.
In Dr. Thaddeus’s critique, he cited evidence he gathered that suggested Columbia had made its undergraduate classes look smaller, its instruction spending look greater and its professors look more highly educated.
The next edition of the rankings is scheduled to come out in September, officials said. To help prospective students navigate without it, Dr. Boyce said Columbia planned in the fall to publish a Common Data Set, a loosely standardized set of statistics used by higher educational institutions. She said it would include much of the same information that is included in the U.S. News profiles.
Dr. Thaddeus said he understood that Columbia had prepared such data sets in the past for its own internal use but did not make them public.
“The point is that they have documents that would shed light on their past submissions to U.S. News — and might even reveal whether their misrepresentations were intentional or unintentional — but they refuse to make them public, even after an overwhelming majority of the faculty who voted asked them to do so,” he said.
Mr. Chang, the spokesman, declined to comment on Dr. Thaddeus’s remarks about the Common Data Set but noted Columbia’s pledge to publish a data set this fall. “The university has long conducted what it believed to be a thorough process,” he said. “Our goal is maximum accuracy and transparency.”
Critics have said that the U.S. News formula tends to reward schools based on wealth and reputation.
In his analysis, Dr. Thaddeus, who specializes in algebraic geometry, found that key supporting data submitted by Columbia was “inaccurate, dubious or highly misleading.”
This year, Columbia rose one spot in the rankings to No. 2; the university was surpassed only by Princeton and tied with Harvard and M.I.T.
Dr. Thaddeus noted that Columbia was ranked 18th in 1988, a rise that he suggested was remarkable. “Why have Columbia’s fortunes improved so dramatically?” he asked in his analysis.
Columbia is not the first university to have its rankings data questioned.
This year the University of Southern California pulled its education school out of the U.S. News rankings because of inaccuracies in data that went back five years. And a former dean of Temple University’s business school was found guilty last year of using fraudulent data between 2014 and 2018 to improve the school’s national rankings and increase revenue. The school’s online M.B.A. program was ranked best in the country by U.S. News & World Report in the years that he falsified data.