Where’s Waldo? It’s a question that has puzzled readers for decades as they patiently comb through incredibly detailed pictures of crowd scenes looking for a tall bespectacled man in a red and white striped jersey and matching hat. The series – known as Where’s Wally? in the UK – was created by English illustrator Martin Handford, and has spawned an empire of books, video games, a TV show, and a possible future movie (Hollywood, please cast Stephen Merchant in the iconic role). Searching for Waldo, or Wally, or Holger (if you’re Danish) is an interesting and easy way to keep a child quiet for a bit, but surely that’s about it, right? Well, what if I told you that there’s nothing random about where Waldo is? What if I told you that there is in fact a foolproof scientific method of finding the man. Computer scientist Randal Olson decided to determine where precisely you can find Waldo. He did it for fun; he swears it’s just for fun. “As I found myself unexpectedly snowed in this weekend, I decided to take on a weekend project for fun. While searching for something to catch my fancy, I ran across an old Slate article claiming that they found a foolproof strategy for finding Waldo in the classic “Where’s Waldo?” book series. Now, I’m no Waldo-spotting expert, but even I could tell that the strategy they proposed there is far from perfect … I was going to pull out every machine learning trick in my tool box to compute the optimal search strategy for finding Waldo. I was going to crush Slate’s supposed foolproof strategy.” Take that, Slate.
Using Slate‘s data, Olson performed a kernel density test as well as some mathematics–including, of course, the hillclimber algorithm-–and scientific-looking stuff which I don’t understand (but I still nodded sagely as I looked at the pretty graphs and things that Olson made.) Here are some takeaways: “If Waldo isn’t on the bottom half of the left page, then he’s probably not on the left page at all … Waldo seems to prefer to hide on the upper quarter of the right page … Waldo also has an aversion to the bottom left half of the right page. Don’t bother looking there until you’ve exhausted the other hot spots.” Olson has not decided which area of study he will pursue next, but I’m really hoping he comes up with an algorithm to solve Magic Eye pictures.