I knew that [Martin] Handford had placed Waldo in each of these illustrations, and in my experience, all people—even people who make a living hiding cartoon men in cartoon landscapes—have tendencies, be they conscious and unconscious. True randomness is very difficult to achieve, even if you want to, and according to Handford he does not necessarily aim for unpredictability. “As I work my way through a picture, I add Wally when I come to what I feel is a good place to hide him,” he once told Scholastic. Knowing this, is it possible, I wondered, to master Where’s Waldo by mapping Handford’s patterns?
I sought to answer these questions the way any mathematician who has no qualms about appearing ridiculous in public would: I sat in a Barnes & Noble for three hours flipping through all seven Where’s Waldo books with a tape measure. ...
What we do see, as highlighted in the map below, is that 53 percent of the time Waldo is hiding within one of two 1.5-inch tall bands, one starting three inches from the bottom of the page and another one starting seven inches from the bottom, stretching across the spread.
So, if you want to find Waldo on any given page, a good strategy would be to start by scrutinizing these two bands first, before moving on to other areas. Although 1.5 inches isn’t a particularly narrow range, it’s small enough to focus on without missing Waldo; and over half the time, he’ll be there.
--Ben Blatt, Slate, on Waldo's tendencies