The human brain is remarkable at recognizing patterns. In fact, humans are so adept at connecting dots and filling in blanks that we quite often see patterns that don’t exist. We like to put ideas, stories, images, etc. into nice, tidy and complete packets; it helps us sleep better at night. But we’re prone to filling in details skewed by our preconceptions. That’s why conspiracy theories will always exist, ghosts will always be seen in moonlit rooms and why you see a complete triangle that doesn’t exist in the Kanizsa image below.
For statisticians, it’s why we’ll always have to explain how large variations and “trends” can be meaningless. I got roped into being an unbiased arbiter in a heated dispute about a manufacturing process improvement. Half the group wanted the project dead and the other half had $50 million a year riding on its success. I showed a graph that I thought told a pretty compelling story in favor of advancing the project. It ended up being a perfect Rorschach. One person went so far as to say, “any rational person looking at that would see an overwhelming significance!” Others were more than underwhelmed.
While statisticians seek new ways to visualize data we ought to keep in mind the brain’s uncanny ability to identify spurious patterns.