Thursday, September 1, 2011

QRF explained in detail

I'm getting a lot of feedback wondering how to explain the new QRF and how it is different than the previous formulas. Here is the basic answer

Old formulas used to be:
Predetermined value (based on opponent class) / number of games played

New QRF is:
Predetermined value (based on opponent class) * number of opponent wins / number of games played

That's it. The old QRF that incorporated margin of victory added another parameter, but that is all.

So how would this have looked last year? Posting all of the results for every team in every sport would not be a fun read, so let's look at an example of one team (I've chosen Owatonna because they play a mix of AAAAA and AAAA schools, and also went 5-3 last year so we can see how winning and losing affects the QRF).  I'll do another post later that covers an entire Class.

Owatonna 2010 Football Page

Game# Opponent PF PA QRF Opp.
Wins
1 L Wayzata 14 42 30 6
2 L Mankato West 8 21 35 8
3 W Albert Lea 17 14 50 2
4 L Rochester Century 7 34 42 8
5 W Winona 49 19 65 3
6 W Rochester Mayo 14 9 110 5
7 W Faribault 35 6 80 4
8 W Rochester John Marshall 42 10 74 3

The "QRF" column shows how many points the Huskies would have earned for each of their 8 games last year.

Here it is in order of points earned.


Game# Opponent PF PA QRF Opp.
Wins
6 W Rochester Mayo 14 9 110 5
7 W Faribault 35 6 80 4
8 W Rochester John Marshall 42 10 74 3
5 W Winona 49 19 65 3
3 W Albert Lea 17 14 50 2
4 L Rochester Century 7 34 42 8
2 L Mankato West 8 21 35 8
1 L Wayzata 14 42 30 6

The actual QRF number that gets posted to the site and is used in comparing to other teams is the average of the individual game QRF's.  In Owatonna's case, the number that would be tied to them is 60.8.

Using the above principals applied to all of the teams in 2010 Section 1AAAAA, the seeding would have been:

  1. Rochester Century (8-0) 69.9
  2. Lakeville North (6-2) 62.3
  3. Owatonna (5-3) 60.8
  4. Lakeville South (5-3) 54.5
  5. Rochester Mayo (5-3) 53.0
  6. Rochester John Marshall (3-5) 43.1
  7. Farmington (1-7) 23.3
The only switch from how they were actually seeded would've been Owatonna and Lakeville South flipping seeds, mostly because Owatonna's opponents were 39-25, while Lakeville South's opponents were 33-31.

As most people know, Lakeville South ended up winning the Section, avenging an earlier loss to Lakeville North and then rolling over Century in the final.  But that is why we play the games on the field and not the QRF.

The QRF is NOT a predictor of what will happen.  It is a way to give proper credit to how a team has already played.