Late last year, the journal Science published a study that suggested door-to-door canvassing could increase support for same-sex marriage. That study, by Michael LaCour, a doctoral student of political science at the University of California, Los Angeles, and Donald Green, a professor of political science at Columbia University, was picked up by several news organizations mostly because of its far-reaching implications.
But when other researchers tried to replicate the data, they failed. In a paper titled Irregularities in LaCour, David Broockman, an assistant professor at Stanford University; Joshua Kalla, a graduate student at the University of California, Berkeley; and Peter Aronow, an assistant professor at Yale University, wrote that the data set in the Science paper "was not collected as described." They also provide a timeline of how they came to their conclusion.
Here's what happened next, according to Green's letter to Science, published in the blog Retraction Watch, which tracks such issues:
"I brought [the] report to the attention of Lynn Vavreck, Professor of Political Science at UCLA and Michael LaCour's graduate advisor, who confronted him with these allegations on Monday morning, whereupon it was discovered that [the] on-line survey data that Michael LaCour purported to collect could not be traced to any originating Qualtrics source files. He claimed that he deleted the source file accidentally, but a Qualtrics service representative who examined the account and spoke with UCLA Political Science Department Chair Jeffrey Lewis reported to him that she found no evidence of such a deletion. On Tuesday, Professor Vavreck [asked] Michael LaCour for the contact information of survey respondents so that their participation in the survey could be verified, but he declined to furnish this information. ... Michael LaCour's failure to produce the raw data coupled with the other concerns noted above undermines the credibility of the findings."
Green asked Science to retract the article. The journal told Retraction Watch that it takes "this case extremely seriously and will strive to correct the scientific literature as quickly as possible."
LaCour, in a statement on his website, writes he is "gathering evidence and relevant information" to provide a single, comprehensive response to the allegations.
The study attracted widespread publicity when it was published last December. Articles appeared in The New York Times, The Wall Street Journal and The Washington Post, among others; WBEZ's This American Life aired a segment on the paper, which it has now retracted. The show's host Ira Glass writes:
"Last month we did a story about canvassers who'd invented a way to go door to door and, in a 22-minute conversation, change people's minds on issues like same sex marriage and abortion rights. We did the story because there was solid scientific data published in the journal Science — proving that the canvassers were really having an effect. Yesterday one of the authors of that study, Donald Green, asked Science to retract the study. Some of the data gathered by his co-author seems to have been faked.
"Our original story was based on what was known at the time. Obviously the facts have changed. We'll update today as we learn more."
The show has appended a note to its original story.