Mathematical Power Rankings Explained
The 2013 CFL Power Rankings ‘mathematical edition’ uses an objective measurement of a team’s performance to date to establish a team’s ranking.
The 2013 statistical model – formulated using a statistical tool known as regression analysis – is based on information gathered from all regular season games played during the 2004 to 2011 seasons, inclusive – over 1,250 observations in total.
The results of the regression analysis suggest that the ten most statistically significant indicators of team success are:
1. Quarterback Efficiency Rating
2. Time of Possession, as measured by percentage
3. Rushing Yards
4. Turnovers on Downs
6. Sacks Taken
7. Punt Return Yards
8. # of Punts
9. # of Kick-Offs
10. # of Kick-Off Returns
Our regression model suggests that a team’s offensive score in a game may be represented by the following formula:
Quarterback Efficiency Rating x 0.125, plus
Time of Possession (%) x 8.38, plus
Rushing Yards x 0.0246, less
Turnovers on Downs x 1.54, less
Fumbles x 0.562, less
Sacks Taken x 0.537, plus
Punt Return Yards x 0.0238, less
# of Punts x 0.314, plus
# of Kick-Offs x 2.99, plus
# of Kick-Off Returns x 0.467.
Each week a Club’s “weekly score” will be determined by calculating a Club’s offensive score, using the formula above, then subtracting its opponent’s score calculated using the exact same formula.
Once a weekly score has been determined, the Power Rankings will be determined:
1. For the first half of the season by taking each week’s score and weighting them evenly (for example, the Power Rankings in week 4 would weight each week 25%, week 5 would weight each week 20%, and so on), except for the first week, which is based 50% on the regression score and 50% on last year's standings; and
2. For the second half of the season, after Labour Day, by weighting the current week 20%, the immediately prior week 10%, and all other weeks 70%.