An interesting tendency:

By the time Project Blue Book folded in 1969, it had evaluated 12,618 reports of sightings. … Special Report Number 14 [is] a vast statistical analysis of 3,201 UFO cases, with hundreds of graphs, tables, charts, and maps. … According to the report, about 22 percent of sightings were declared “unknown.” That means their origin couldn’t be determined even after all the evidence was in—these were objects that didn’t look like airplanes or balloons or any other discernible vessel. They maneuvered in strange ways, hovering or changing speed and direction suddenly. Sometimes witnesses, many of them Air Force pilots, described seeing actual saucer- or cigar-shaped objects. Unknowns tended to be cases with better information: 35 percent of “excellent” sightings—those with more reliable witnesses and, sometimes, corresponding physical evidence—defied explanation; only 19 percent of poor ones did. And the longer a sighting lasted, Friedman says, the more likely it was to remain unexplained: 36 percent of unknowns were seen for more than five minutes. (more)

Since things with fewer details are seen more in far mode, and since in far mode we are more confident in our theories, we should expect people to be more confident in their classifications of things that have fewer details, and so have a smaller fraction of things left as hard to explain. I’d like to see this tested elsewhere, such as planes seen near or far, or crimes known in little or much detail.

More:

In 1997 a CNN poll found that 80 percent of Americans think the government is hiding information about UFOs, and 64 percent believe that extraterrestrials have contacted humans. In a 2007 Associated Press poll, 14 percent said they’d seen a UFO. … At the end of his lectures, [Friedman] often asks the audience how many of them have seen a flying saucer. … Usually ten percent of the audience have their hands raised. … “But then I ask, ‘How many of you reported what you saw?'” Nearly every hand drops.

Thats a whole lot of skeptics of the usual official UFO story. (I’m not a skeptic.)