Week 12 NFL Predictions (model v1.1)

I tweaked the model somewhat. While I have not fully minimized the extremely high/low probability scenarios, those will occur less often in the current version of the model (1.1). This model will still tend to pick the same winners as the previous version, but the predicted scores and win probabilities are somewhat different.

The difference between this version and the previous is actually more of a bug correction than a substantive change. The previous version used each team's average score for the season to that point as a starting point. It then shifted that starting point up or down based on how well the team does relative to an overall average of teams along with factors related to the specific opponent. Therefore there was some redundancy such that a team that is better than average will start with a better than average score and then be further shifted up. So this version starts everyone at the overall average and simply shifts that value based on how well a given team has been doing and the specific opponent. It's a subtle distinction, but one that should predict fewer blowouts. That appears to be the case. Below are predictions using v1.0 and then v1.1. I added the predicted margin along with the point spread set by Vegas to see how the model does not just in terms of picking winners but against the spread (ATS).

Version 1.0

Away	Home	Away Score	Home Score	Away probability	Predicted Margin	Vegas Spread
Packers	Lions	39	16	0.97	-23	-10
Raiders	Cowboys	13	27	0.18	14	13.5
Giants	Broncos	28	18	0.8	-10	-6.5
Browns	Bengals	15	26	0.22	11	13.5
Buccaneers	Falcons	15	36	0.06	21	12
Dolphins	Bills	28	14	0.87	-14	-3
Seahawks	Rams	23	11	0.82	-12	-4
Panthers	Jets	16	23	0.26	7	3
Redskins	Eagles	10	28	0.07	18	9
Colts	Texans	31	19	0.85	-12	-3.5
Chiefs	Chargers	12	34	0.006	22	13.5
Jaguars	49ers	19	22	0.39	3	3
Cardinals	Titans	34	21	0.82	-13	3
Bears	Vikings	19	40	0.05	21	11
Steelers	Ravens	20	23	0.42	3	2.5
Patriots	Saints	35	46	0.23	11	2

These picks are not particularly controversial but several of the probabilities tend to be extreme.

Version 1.1

Away	Home	Away Score	Home Score	Away probability	Predicted Margin	Vegas Spread
Packers	Lions	35	18	0.93	-17	-10
Raiders	Cowboys	9	26	0.09	17	13.5
Giants	Broncos	23	22	0.56	-1	-6.5
Browns	Bengals	12	26	0.13	14	13.5
Buccaneers	Falcons	19	33	0.14	14	12
Dolphins	Bills	26	19	0.71	-7	-3
Seahawks	Rams	25	14	0.81	-11	-4
Panthers	Jets	17	24	0.29	7	3
Redskins	Eagles	14	23	0.2	9	9
Colts	Texans	26	18	0.77	-8	-3.5
Chiefs	Chargers	16	29	0.05	13	13.5
Jaguars	49ers	20	23	0.41	3	3
Cardinals	Titans	31	21	0.76	-10	3
Bears	Vikings	20	31	0.18	11	11
Steelers	Ravens	19	21	0.44	2	2.5
Patriots	Saints	28	32	0.41	4	2

In the second set of predictions the average absolute value of the point difference is 9.25 compared to 13.44 in the first version. Neither value is necessarily clearly better. The average margin of victory for the last two weeks were 9.38 and 8.19, but three weeks ago it was 13.92.

I hope to make a few additional changes soon, but I wanted to get these numbers up before the majority of the games were played.