Measuring NFL team performance
by quarterback stats
A neural networks approach
By David Michlig
EC 539
Teams (and fans) want victories!
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The quarterback is the leader of the team
Typically, the quarterback stays with a team to play if they
have a good season
A neural network approach to determining how the
performance of the quarterback affected the overall team
performance can make the decision of who to play easier
How important is the quarterback, anyway?
Data used
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Collected stats from 46 active quarterbacks in the league
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Game played, completions, attempts, completion , yards, yards
per play, touchdowns, interceptions, fumbles, passser rating,
rush attempts, rushing yards, rushing average, rushing
touchdowns, and first downs.
Number of wins was used as the classes
Used seasons where quarterback played in 10 or more
games
In total, over 200 individual seasons were used
Project procedure
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I plan to use pattern classification methods to determine
relationship between quarterback performance and team
wins
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Nearest Neighbor algorithm
Maximum Likelihood
Is the quarterback truly the leader of the team, or just
another factor?
Initial results
kNN testing rate (no normalization)
12
classification rate
10
8
6
4
2
0
1
2
3
4
5
6
7
8
9
10
k
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Very low classification rate, which doesn’t look promising.
The confusion matrix, however, shows that although it’s
not usually an exact prediction, it is often within a few
games of the true record
Future results
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There are many outside factors that need to be
considered
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Injuries
Quality of the team overall
Defense
Protection
The quarterback does not have a say in these things!
Based on initial results, however, it seems that although
exact classification may not be possible, estimates may be
made.