SLOWLY BUT SURELY, statistical analysis is coming to hockey. At least one-third of NHL teams are using advanced metrics to evaluate players, and next-level numbers are leaking into game-day stories and blogs. The NHL has given this stats boom a boost by making shooting, power play and penalty data since 1997 available on its website, alongside "real-time scoring stats," which include hits, blocks, giveaways and takeaways. It's a fascinating trove of data, and hockey metricians have begun to boil and stir the numbers into all sorts of concoctions.