SAI Metrics - Frequently Asked Questions

What are SAI Metrics?

SAI Metrics are objective measures derived from modeling the underlying processes of the given sporting event.

What is the Contribution to Winning Index (CWI)?

CWI is each player’s contribution to winning over 80 games compared to the "average" player. The average player would have a value of 40 implying that if two teams consisting of average players would play an 80 game season, each team would win 40 games.

Compare Players’ Contributions to Winning

Below is a comparison of 4 centermen: Ryan Getzlaf, Evgeni Malkin, Wayne Primeau and Derek Armstrong.

If two teams consisted entirely of average players except one of the teams had Getzlaf in the lineup, the team with Getzlaf would win approximately 46 games. Similarly, Armstrong costs his team approximately 2 wins over 80 games.

Also, Getzlaf would contribute 1.62 more wins than Malkin, 4.82 more wins than Primeau, and 7.91 more wins than Armstrong.

Why is the Contribution to Winning Index based on 80 games?

80 is easier to work with than 82 (the actual number of games in an NHL season).  When a player's CWI is greater than 40, they are contributing to winning.  If their CWI is less than 40, then they are contributing to losing.  If CWI was based on 82 games, the threshold between contributing to winning and losing would be 41 which is slightly more difficult to work with.

What is Theoretical Goals For (TG For)?

This statistic replaces shots on goal. This statistic accounts for the fact that all shots are not created equal by calculating the probability that each shot taken while they are on the ice will result in a goal.

What is Theoretical Goals Against (TG Against)?

Analogous to TG For, TG Against is the probability that their opponent scores a goal when they are on the ice.

What is Theoretical Goals Plus-Minus (TG Plus-Minus)?

This statistic replaces the plus-minus statistic that is currently used.  It is calculated by: TG For minus TG Against; and is the net number of goals that a team will score while the player is on the ice.