Down With the Perfect 10!
A mathematician explains the genius of the new gymnastics scoring system.
Check out Slate's complete coverage of the London Games.
Photo by BEN STANSALL/AFP/GettyImages
The 2012 Olympic Games in London will use a relatively newfangled system for scoring gymnastic routines. The revamped rules, which debuted in Beijing in 2008, make an athlete’s artistry less important than her ability to string together loads of technically difficult moves. Today’s system has also eliminated what used to be the pinnacle of gymnastics achievement: the perfect 10. Four years ago, Jordan Ellenberg argued that the new scoring was more in line with the Olympic spirit of “faster, higher, stronger,” and he advised lovers of the perfect 10 to get over it. His original piece is printed below.
Olympic gymnastics has a new scoring system, and not everyone's happy with the departure of the famous 10-point scale. "It's crazy, terrible, the stupidest thing that ever happened to the sport of gymnastics,"wailed excitable supercoach Bela Karolyi in the New York Times. "How could they take away this beautiful, this most perfect thing from us, the one thing that separated our sport from the others?"
What exactly is Karolyi kvetching about? This year, competitors get two scores, each from its own panel of judges. The "A" score measures the difficulty of the routine. A relatively easy move like a one-handed cartwheel on the balance beam adds 0.1 to your A score, while bringing off the astonishing Arabian double front layout rakes in 0.7. (And no, you can't inflate your score by doing 10 cartwheels in a row; only the 10 most difficult elements are counted, and repeated elements don't count at all.) Performing two or more elements in close succession tacks on "connection value" of up to 0.2 points per transition. The way to max out your A score, then, is to cram the toughest possible moves into your routine and pack them as tightly together as you can manage.
The downside of all that: In the middle of your painstakingly computed, ultra-difficult, absolutely seamless routine, you might fly headfirst off the end of the beam. That's where the B panel comes in. The B score starts at the top of the scale rather than the bottom, and every mistake takes you further from a perfect 10.0. The new system imposes a kind of mandatory minimum sentencing; after years of complaints about unobjective scoring, judges on the B panel now have less discretion about how many points to deduct for a given miscue. The standard penalties are also harsher than they used to be—a fall that would have cost a half-point in Athens now means a 0.8-point deduction. That's why American gymnast Nastia Liukin's botched dismount at the end of Sunday's brutally difficult uneven bars routine—a routine specifically designed by her father to ring up a massive A score—dropped her back to fifth place, behind several less ambitious competitors.
The final tally is the sum of the A score and B score; since the difficulty of the current batch of Olympic routines tops out in the 7s, you can expect medal-winning scores to be somewhere in the 16s. And that's one thing opponents of the new system don't like. "A perfect 16.9" lacks the ring of "a perfect 10."
"It's hard to understand. I don't even understand it," Mary Lou Retton told the Times. "Back in the old days you'd know what that means," sniffed NBC commentator Tim Daggett (himself the recipient of a 10.0 on the high bar in the 1984 Games) after watching China's Yibing Chen score a 16.275 on the vault.
But would you really? Under the old system, a 10.0 didn't mean "perfection"—the score for a flawless performance was computed by adding difficulty bonuses to a fixed "start value" (8.4 for men, 8.8 for women) up to a maximum of 10, then taking deductions for mistakes. An easier routine, carried out perfectly, might get a 9.6 instead of a 10. In other words, the old system was a lot like the new system. If anything, the new scoring is easier to interpret: A B score of 10.0 is synonymous with absolute perfection while the old unified score was an impenetrable combination of pluses and minuses arrived at only after Talmudic contemplation of the FIG's Code of Points.
But let's not focus on those details. As in most emotional disputes about numbers, people aren't arguing about precisely how the number is calculated but what it symbolizes. How we measure something reflects, and eventually influences, what we value in it. And in that view, the new scoring system really does represent a profound change.
Scales with a hard upper limit, like the old gymnastics scoring or the SAT, say that what's important is the pursuit of perfection. The goal of the SAT is to blacken the right bubble for every last one of those inequalities and analogies, and you can do no better than getting every one correct. Open-ended scales, like the new gymnastics system, value innovation and the breaking of existing barriers. You can't imagine men's weightlifting, say, being scored on how close you came to clean-and-jerking 550 pounds, with every pound above that not counting toward your score. That's because the goal of weightlifting isn't to approach a predetermined ideal. The goal—primal, simple, and satisfying—is to hoist a more awe-inspiring heap of metal above your head than the other fellow. Or, better yet, to hoist more than any other fellow in history.
Jordan Ellenberg is a professor of mathematics at the University of Wisconsin. His book How Not To Be Wrong is forthcoming. He blogs at Quomodocumque.
Photograph of Nastia Liukin by Kazuhiro Nogi/AFP/Getty Images. Photograph of Mayu Kuroda on the Slate home page by Franck Fife/AFP/Getty Images.