PDO in College Hockey


If you’re not convinced by now that puck possession matters, you might as well go ahead and close this tab. Corsi is real, and it’s here to stay – yes, even in college hockey. Ryan Lambert at College Hockey News pretty much dropped the mic on the issue as the 2015 conference tournaments started, so I won’t waste any more words on it.

Though if you’d like to be spared from an RL article, I’ll just say this: of the top 20 CF% teams in the NCAA, 60% made the tournament (12/20). Of the 39 other teams, 10% made the tournament (4/39). More possession, more shots, more goals, more wins. What’s not to get?

The next thing everyone always brings up is, “yeah but shot quality.” Sorry, but shot quality is not a game plan, nor something even the best players can sustain. If your team has a high shooting percentage, it’s likely to regress the more they play. Same with save percentage. Hot goalies are usually just that – hot. Until they’re not, because .925 simply isn’t sustainable for most goalies. Eventually they’re going to have a few .795 nights.

The stat that measures all of that, of course, is PDO. Puckology has a great post on this. PDO adds the team shooting percentage and save percentage into one stat. The baseline for this stat is 100.0, because that’s the league average – always was and always will be (the average of all shot percentages in the league plus the average of all save percentages will always be 100%). So every team in a league will ultimately regress toward a PDO of 100.0. Your incredible goaltending will falter, your super-lucky “shot quality” will come down. That’s the nature of the game – regression to the mean is a statistical fact.

So here’s where things get interesting, and where I always got a little hung up: what I just said above isn’t 100% true. The baseline for every team or player probably is not 100%. The Chicago Blackhawks have more talent than the Arizona Coyotes, yes. But this is the NHL we’re talking about – each of those 30 teams is among the most talented hockey teams in the world (yes, even Buffalo). The baseline for the Blackhawks might be higher than the Coyotes, but not much. We’re talking about a thin band: PDO in the NHL ranges between 97.0-102.0. So is PDO talent? Probably not very likely in the NHL – it’s just variance from the mean, indicating likelihood of regression.

But is that still true in college hockey? You don’t have the same talent parity as in the NHL – most people wouldn’t put Boston University and Niagara in the same sentence. No one will argue there’s not a significant talent gap there. Sure enough, the PDO range in the NCAA is much larger than in the NHL – 95.7-104.5.

Therefore, PDO in college hockey might not be as indicative of unusual good/bad luck as it is in the NHL. Some teams might just have a naturally higher or lower baseline because of a higher level of quote-unquote talent.

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The New Broken Arrows


You might be aware that the United States dropped a nuclear weapon on North Carolina. Unintentionally, of course. A B-52 bomber collided with a refueling tanker mid-air, and the plane had to jettison its nuclear payload. Some official reports suggested one of the hydrogen bombs may have been armed. Had it detonated, it would have incinerated most of North Carolina, then dropped radioactive fallout on Washington, D.C. all the way up to Boston. But we’ll never know if it was armed, because the weapon’s nuclear core sank so far into a swamp it was unable to be recovered. It’s still there today.

Of course, maybe you weren’t aware of this. The details of the incident were only declassified in 2013, even though it occurred more than 40 years ago.

It’s one of hundreds of previously undisclosed nuclear “Broken Arrows” that occurred under the watch of US Strategic Air Command (headquartered in good ol’ Omaha, Neb.). These incidents and many more are documented in Eric Schlosser’s “Command and Control: Nuclear Weapons, the Damascus Accident, and the Illusion of Safety.”

Schlosser’s investigating uncovered a huge list of near-misses with nuclear weapons throughout the Cold War. His narrative is built around another major incident – the explosion of a Titan II long-range missile in rural Arkansas. That blast killed one serviceman and launched a thermonuclear warhead 80 feet into the air before it landed intact in a nearby ditch.

You’d think these incidents would be more well known, but naturally Strategic Air Command was eager to bury details of the reports, in the name of national security and keeping strategic and technical details out of the hands of the Soviet Union. From the book:

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