While the title of our blog is Sports Opinionated, that doesn’t preclude us from searching out some facts to back up our opinions. Unfounded opinions are generally just hot air, and stats without context are useless. We aim to give you our view, but to back to at least back it up with facts.
Traditional sports stats have long shown only a part of the picture, and there are now many more advanced metrics available to us in all the major sports. For those who have absolutely no exposure to the role that stats can play in major sports, I would recommend the book Moneyball by Michael Lewis as an excellent introduction as it speaks to the common sports fan by outlining the success of the Oakland A’s GM Billy Beane.
Moneyball: The Art of Winning an Unfair Game
There are a variety of resources all over the web, which outline different ways of evaluating the game and it’s players. Here are just a few of the stats, an explanation and the sites we pull them from.
Football Outsiders – a fantastic website devoted to a deeper analysis of football success
DVOA – this is an efficiency statistic that stands for Defense-Adjusted Value Over Average. Don’t be fooled by the name, it is essentially a percentage that shows how much better/worse a player is than the average player at his position. It is on a per play basis. Positive percentages show a better than average success rate while negative numbers are worse than average. The stat evaluates how many of a player’s touches were “successful” based on progress towards first downs. DVOA is also used evaluate offense and defense as a whole, and can be split between running and passing plays or different formations, etc.
DYAR – this is a total value stat that stands for Defense-Adjusted Yards Above Replacement. The purpose of this statistic is to evaluate the total yardage value of a player compared to the average league backup or replacement. Anything that is positive shows that the player is better than replacement level and negative is worse.
ALY - this is a statistic for the running game known as Adjusted Line Yards. A statistical model is used to explain how effective the offensive line or defensive front 7 is in the running game. It is shown as an average yards per carry.
Advanced NFL Stats – a great analytical site that focuses on win probabilities and coaching decision-making
WP - also known as Win Probability. It takes into effect the down, distance, current score, time and position on the field to determine the probability that a given team will win the game at any given moment. Probably a betting man’s favorite stat.
Behind the Net – both a statistical website and a blog dedicated to taking a deeper analytical look at hockey players
GVT – Goals Versus Threshold is a total value stat created by Tom Awad to show a players value versus replacement level. It shows total contribution for Even Strength, Powerplay and Short-handed while approximating playing time. However, it is a count stat, not a rate stat, so more games can result in a higher GVT.
Rating – I often refer to this as Comparative +/- just because the term “Rating” can be deceiving. The stat is essentially the difference between a players +/- and the +/- of his team when he’s not on the ice. It is a mehod for determining the players value versus the rest of his team, in order to compensate for the effect of players on good or bad teams. This is on a per 60 minute basis.
GFON/60, GAON/60 – a method for showing the Goals For and Goals Against when a player is on the ice, but normalized for each player’s icetime by stating it per 60 minutes.
GFOF/60, GAOF/60 – the exact same stat as above, except it shows Goals For and Against when the player is NOT on the ice. It can be very valuable to evaluate a player’s offensive or defensive contribution by comparing either of these stats when a player is on and off the ice.
Corsi % - a measure of possession. The metric was developed by Buffalo Sabres goaltender coach, Jim Corsi. The idea is to compare the number of shots directed at the opponents net, versus the number directed at the players own net. Directed shots would be the combination of shots on goal, shots that missed goal and shots that were blocked. Corsi% is the ratio of total shots directed at the opponents net when the player is on the ice. 0.500 would mean the shots were even, 0.550 would be great. The whole point to evaluating Corsi is that shots directed on net lead directly to goals, so the better the shot differential, the better chance a team has to win.
Fenwick - very similar to Corsi but doesn’t count a blocked shot as an attempt. Since shot-blocking can be assumed as a skill, the Fenwick (named after Matt Fenwick as far as I can tell) number is a better indicator of possession and results of possession than Corsi.
Zone Starts - given all attention on possession stats (Corsi & Fenwick above), it makes sense to understand if a player is being used primarily in an offensive or defensive role. Obviously a center who is always deployed for faceoffs in his own end is starting in a much less advantageous positition than one who starts his shift in the offensive end. zone starts can be used to adjust the Corsi or Fenwick or else can be used to determine how a coach deploys certain players or lines.
Ice Hockey Metrics – a blog run by Timo Seppa, a writer on both Puck Prospectus and creator of the ESTR stat
ESTR – is a rate stat that gives offensive, defensive and total contributions per 60 minutes of play. 0 is league average, so a positive or negative value show comparison to the average player.
