- David A. Holmes did not wake up one morning and say to himself, Today I’m going to come up with an equation to measure the perfect human posterior. He didn’t think to quantify backsides until a horseracing public-relations person called to ask if he could scientifically calculate what the perfect behind for a jockey would be. Holmes, a psychologist at Manchester Metropolitan University, knew it wasn’t so simple. “There’s an awful lot more to bums than you might think,” he says.
The equation that describes the quality of the female rear end, according to Holmes, is (S + C) x (B + F)/T - V, where S = Overall Shape (“including tendency to droop”), C = Circularity, B = Bounce Factor (not to be confused with “wobble”), F = Firmness (with perfect being “like a comfy bed”), T = Skin Texture and V = Vertical Ratio (the goal: “on the top-heavy side of symmetrical”). For the male rear end, the equation replaces bounce, circularity and vertical ratio with M (Muscularity), L (Leanness) and O (Overall Symmetry).