Ben Blatt dishes on how best to find the striped loiterer:

[Creator Martin] Handford generally shies away from putting Waldo near the bottom or top of a page, which leads me to theorize that Waldo placement is largely a function of two factors: aversion from extremes and aversion from the middle. While we would expect Waldo to be hidden within an inch-and-a-half of the spread’s top or bottom borders almost 25 percent of the time if Handford were placing him randomly, in practice he is there only in 12 percent of all pages. More surprising is the fact that Waldo is also unlikely to be in the middle of the page. … It’s possible that Handford avoided the edges and centers of the pages out of concern that they may not print clearly. However, Waldo is placed in these locations occasionally, which weakens this hypothesis. I think it’s more likely that Handford was trying to avoid locations that might be construed as too obvious—i.e. the centers or the corners, where children and adults alike might begin their search. But while this might make Waldo harder to find for the reader whose eyes immediately dart to the center or edge of the page, once you know your quarry is unlikely to be in those places, it actually makes him much easier to find.