A widely publicized study looking at changing voter opinions on gay marriage was the focus of much media attention this week after its coauthor, citing concerns about the validity of the research, requested its retraction. Science, the journal that published the study, issued an official retraction Thursday.
The study, titled, "When contact changes minds: An experiment on transmission of support for gay equality," by UCLA researcher Michael LaCour and Columbia University professor Donald P. Green, was published in December. The paper claimed to find that gay canvassers with a personal stake in same-sex marriage rights were more persuasive in effecting long-term changes of opinion in survey respondents than straight pollsters.
But after two researchers raised serious questions about a lack of data and funding details outlined in the study, Green wrote to Science asking that it be retracted.
"Michael LaCour's failure to produce the raw data coupled with the other concerns noted above undermines the credibility of the findings," he wrote. "I am deeply embarrassed by this turn of events and apologize to the editors, reviewers, and readers of Science."
LaCour stood by his findings, Tweeting on May 20 that he was gathering information to assemble a "single comprehensive response," and posting a statement on his website that read, "I will supply a definitive response on or before May 29, 2015. I appreciate your patience, as I gather evidence and relevant information, since I only became aware of the allegations about my work on the evening of May 19, 2015, when the not peer-reviewed comments in 'Irregularities in LaCour (2014),' were posted publicly online."
The reasons for retracting the paper are as follows: (i) Survey incentives were misrepresented. To encourage participation in the survey, respondents were claimed to have been given cash payments to enroll, to refer family and friends, and to complete multiple surveys. In correspondence received from Michael J. LaCour's attorney, he confirmed that no such payments were made. (ii) The statement on sponsorship was false. In the Report, LaCour acknowledged funding from the Williams Institute, the Ford Foundation, and the Evelyn and Walter Haas Jr. Fund. Per correspondence from LaCour's attorney, this statement was not true.
The journal also cited LaCour's failure to produce the original survey data, "from which someone else could independently confirm the validity of the reported findings."
As of midday Friday, LaCour had not posted an updated statement on Twitter or on his website.