With the sphericity of the Earth empirically established by the ancient Greeks more than 2,000 years ago, it is difficult to believe that there are still holdouts. Yet, as a reporter for Vice recently observed, “If a flat Earth conference in Edmonton, Alberta, of all places, can pull in over 200 people … I think we may be underestimating the size of the movement.”

How prevalent is flat-Earthery? In a previous column, we examined what seems to have been the first systematic attempt to assess the American population’s views on the shape of the Earth, a YouGov poll conducted in February 2018. According to YouGov’s report, when asked, “Do you believe that the world is round or flat,” 2 percent of the 8,215 respondents chose “I have always believed the world is flat.”

When we asked YouGov for the data, however, we received a spreadsheet reflecting data for 10,374 respondents, of whom only 1.28 percent preferred the always-a-flat-earther response. Unfortunately, YouGov was unable or unwilling to resolve the discrepancy, making it impossible for us to reach a firm conclusion about the actual size of the flat-Earth movement on the basis of the poll.