FanPost

Lion's Over-Under Win Total: Probabilities Broken Down

Earlier this week Sean posted a poll on the over/under win total for the Lions. Wednesday, when that was posted happened to be my birthday. Why is that important? Well its not, its just an excuse to show off my new Slay jersey!!!

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Oh I guess it does sort of explain why I was drunk on PoD late and decided that "Hey we have the vegas lines for each game we can create the probability of winning a certain amount of games!" If you are thinking wow Cram9030 you are a sad, weird man then you are right. The challenge was a little more than my tired, inebriated mind was up to and I did not get back to it until today.

Basically the idea here is that each Vegas line can be translated into a probability that the Lions will win. A simple explanation of how that is done can be seen here but I used the WP Calculator from Advanced Football Analytics to create the chart below that shows the probability of the Lions winning or loosing each game. The lines I used were the ones provided by Sean with one exception and that is that there was no line for the final game against the Bears but I took the line from the home game and added three for home field advantage.

Win Probability Loss Probability
at San Diego 0.44 0.56
at Minnesota Vikings 0.50 0.50
Denver Broncos 0.50 0.50
at Seattle Seahawks 0.27 0.73
Arizona Cardinals 0.56 0.44
Chicago Bears 0.70 0.30
Minnesota Vikings 0.70 0.30
at Kansas City 0.54 0.46
at Green Bay Packers 0.30 0.70
Oakland Raiders 0.81 0.19
Philadelphia Eagles 0.58 0.42
Green Bay Packers 0.50 0.50
at St. Louis Rams 0.44 0.56
at New Orleans Saints 0.50 0.50
San Francisco 49ers 0.56 0.44
at Chicago Bears 0.58 0.42

We can then use these to figure out how likely it is that we win a certain about of games. We can see below that the most likely amount of wins is for all intensive purposes a tie between eight and nine wins.

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I also went ahead an provided the chart for those how are interested in more specific numbers. Looking at the chart its good to know that as of now we are 10 times more likely to more likely to finish undefeated than defeated so there is that. ;)

Number of Wins Pobability
0 2.69E-06
1 5.86E-05
2 0.000580289
3 0.003478861
4 0.014166167
5 0.041620869
6 0.091387047
7 0.153112288
8 0.197945848
9 0.198191125
10 0.153183003
11 0.090418155
12 0.039939018
13 0.01275344
14 0.002773777
15 0.00036666
16 2.22E-05

Back to the original question though we can get a good idea on the over, under or push probabilities form the chart above by just adding up all the probabilities that would give us an under or and over.

Under 0.304407
Push 0.197946
Over 0.497647

What we see here is that there is pretty much a 50% chance that the Lions hit the over meaning winning between 9 and 16 games. I find the placement of the line at exactly eight a fascinating one by Vegas. If they had chosen 8.5 wins they would be hitting almost exactly 50-50 on the over and the under but they chose to make the push nearly 20% likely. This tells me that they think the betting public will bet 8 just as much as 8.5, basically they are banking that the public will under rate the Lions. From these we can say taking the fandom out of it taking the over is a good bet even with Lions likely to regress.

This is a FanPost and does not necessarily reflect the views of Pride Of Detroit or its writers.