by Andrew Rothstein
Puck Prospectus Reference Page
(Note: Unfiltered will serve as the temporary home for our reference page until we finish updating the site in the coming months. Updates will include the 2009-2010 VUKOTA team depth charts, a statistics page and a reference page.)
Career Scores: Career Scores are a method to estimate a player’s overall value in the first 10 years after the player’s first draft-eligible season. These unusual parameters are set because Career Scores are used only in the development of projections for draft-eligible players. It is not an objective measure of anything, but rather an estimation designed to boil down a player’s approximate value into a single number. Career Scores take into account the player’s play at all levels of the game during those years (major league, high and low minor leagues, even junior and college), giving different weights to each. The calculation is different for forwards, defensemen and goaltenders, but each calculation is designed to give approximately the same distribution of results. A player’s Career Score can be loosely interpreted as follows:
1.00 or higher NHL superstar
.75 to .99 NHL star
.50 to .74 NHL regular/minor league star
.25 to .49 Minor league regular
Defensive GVT: The value of a player, in goals, above what a replacement level player would contribute defensively.
Goals Versus Salary (GVS): Similar to Goals Versus Threshold, GVS measures a player’s offensive and defensive contributions in goals relative to what the team should expect given the player’s salary. The higher the number the better, anything over 10 is considered an excellent value, and anything under -10 is a poor investment. GVS can be used to evaluate if a player is earning his salary, and on a team basis it can determine how well a GM is managing cap money.
Goaltending GVT: The value of a player, in goals, above what a replacement level player would contribute in goaltending.
GVT: Goals Versus Threshold. The value of a player, in goals, above what a replacement level player would contribute. GVT aggregates offensive, defensive, goaltending and shootout contributions in a single metric. The sum of player GVT on a team equals that team’s goal differential plus the replacement level, which is 50% of the average team scoring level.
nGVT: GVT, normalized for league scoring level of 3 goals per game and a schedule length of 82 games. Typical values: 0 is a replacement player, 5 is a third-liner or #4 defenseman, 10 is a second/first liner or #2 defenseman, 20 is a top-10 league scorer or league top-3 defenseman or goaltender, 30 to 35 is MVP-caliber.
Offense-Generating Play (OGP): OGP is used to rate a player’s offensive contributions beyond what is measured in goals and assists. Similar to Shut-Down Play (SDP), it is read and interpreted in the same way as a goaltender’s goals-against-average (GAA or AVG), except that a rating higher than the league average number of goals-per-game is considered very good. It weighs even-strength GFA to power-play GFA in a 4-1 ratio, and short-handed GFA is not considered. Given the importance of power-play GFA, it is generally only used when studying players who are at least occasionally used with the man advantage.
Offensive GVT: The value of a player, in goals, above what a replacement level player would contribute offensively.
QualComp: “Qualcomp” is the average “Rating” of a player’s opponents, which gives a reasonable estimate of the Quality of Competition faced by an individual player.
Quality Start (QS): Similar to baseball, a Quality Start is awarded any time a starting goaltender plays well enough for his team to win. Since a Quality Start is awarded regardless of whether or not the team in front of a goalie scores enough goals to win the game, Quality Starts reduces the bias involved with Goalie Wins. Since it is designed to replace Wins, a goalie who is awarded a Quality Start over half the time is considered good. Quality Starts can also be used indirectly to measure a goaltender’s consistency, and to measure the effectiveness of a team offensively.
QualTeam: is the average “Rating” of a player’s linemates. A positive number generally indicates that he played with the first or second line.
Rating: A player’s “Rating” is his +/- per 60 minutes when he’s on the ice minus his +/- per 60 minutes when he’s off the ice. In other words, it’s his +/- relative to his team. In general, this gives credit to players who play well on bad teams and penalizes poor players on good teams.
Relative Plus/Minus (RPM): A player’s Plus/Minus adjusted for team goal differential and goaltending. RPM subtracts from a player’s +/- 80% of his team’s expected goal differential (since the player is one of 5 on the ice) and adjusts goals against by his team’s save percentage. As for normal +/-, the average value is 0. A +20 player would be among the league top 10, and +30 would be among the top 100 seasons ever.
Shootout GVT: The value of a player, in goals, above what a replacement level player would contribute in the shootout.
Shut-Down Play (SDP): SDP is used to rate a player’s defensive contributions. Similar to Offense-Generation Play (OGP), it is read and interpreted in the same way as a goaltender’s goals-against-average (GAA or AVG), so a rating below the league average number of goals-per-game is considered impressive. It weighs even-strength GAA to short-handed GAA in a 4-1 ratio, and power-play GAA is not considered. Each minor penalty a player takes counts as 0.2 goals against. Given the importance of short-handed GAA, it is generally only used when studying players who are at least occasionally used to kill penalties.
Similarity Score (SIM): Similarity Scores are used to compare one player to another at a specific points of their careers. It looks at differentials in goals, assists and penalty minutes (weighted unevenly), over the current season, preceding season and career totals (weighted evenly) to determine how closely the two players’ statistics match. A zero is an exact match, and anything below a 10 is considered reasonably similar. It is primarily used to find similar players in history in order to help predict future statistics. It is not an index, but rather a formula that is applied to a specific player-season of interest. It does not factor in age, except indirectly through career totals, nor does it use advanced statistics that are available only to certain leagues and eras (e.g. shots, power-play goals, ice-time). It can be applied to statistics adjusted to neutral-era, and it can be applied to statistics that have been translated to an NHL equivalent, but it does not have to be. SIM is most accurate when applied to players with at least 3-5 seasons of statistics.
VUKOTA: Puck Prospectus likes to keep our readers one step ahead of the competition. To this end, we have developed a tool called VUKOTA. Following in the tradition of PECOTA and KUBIAK, VUKOTA is Puck Prospectus’ player projection system. Using a combination of fundamental and advanced statistics, VUKOTA compares current NHL players to comparable players throughout history to best project their next season’s performance in goals, assists and points as well as GVT. VUKOTA will be an additional tool in the Puck Prospectus arsenal to help us and our readers better understand the inner workings of the hockey world. Stay tuned for more VUKOTA goodies on Puck Prospectus as the 2009-2010 season approaches.





[…] Responding to a challenge from Christina, Keith posted the best and worst outfield arms for 2006. Keith took a look at the criterion of preventing runners advancing from second on a single but of course there are other scenarios one could include. Recently, John Dewan published a similar metric in The Hardball Times Baseball Annual 2007 that included all advancement scenarios on singles and doubles. The top and bottom five outfields by his measure were: […]
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