2.5 Underdogs?

FLSeahawk

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The points differential is a function determined by win probability. There is about a 2.5% the game ends up with a 1 point margin of victory. The chance of a 2 point victory is about 2.0% . There's between 8.5 and 9.3% of a 3 point victory. Obviously there's a slightly bigger chance of the favourite winning by any of these margins than the underdog. The probabilities are also altered by the number of points expected to be scored in a game. If the game is more likely to be low scoring the probability of a narrow victory is increased. All the 49ers -2.5 line means is the 49ers are considered to be a 54.7% chance with the Seahawks a 45.3% chance...give or take. If the 49ers were a 52.6% favourite the line would be -1.5. If the 49ers were a 63.7% chance the line would be -3.5.

Just remember that betting handicap points are not equal in value. They don't imply that a team will win by a specific margin or that a team is better by that specific margin. 3 is the biggest number and 7 is the 2nd biggest number. 6 & 10 are the other big 2 numbers. Everything else is pretty small.
Not sure where you got your 1, 2, and 3 point victory percentages from but this is the historical outcomes since 2000. It’s roughly 4%, 4%, and 15% respectively.

Your win probabilities look about right off the top of my head, maybe a hundredth off here or there.

Either way, I’m glad there are actuaries out there that like sports. Moneyball opened a lot of doors after Billy made it famous.
 

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flv2

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Not sure where you got your 1, 2, and 3 point victory percentages from but this is the historical outcomes since 2000. It’s roughly 4%, 4%, and 15% respectively.

Your win probabilities look about right off the top of my head, maybe a hundredth off here or there.

Either way, I’m glad there are actuaries out there that like sports. Moneyball opened a lot of doors after Billy made it famous.
I'm referencing old betting and website data from about 12 years ago. You are quoting newer data, but perhaps you are misinterpreting it. The probability of a 1 point game is about 4.3%, but that's for both teams combined. The probabliity of the favourite winning by 1 point would be a little above 2.15% and the underdog would be a little below it. It's a similar story with other points values. There are recency changes due to the reduced overtime period and the introduction of the 2 point conversion. I don't doubt that the probability of a 3 point victory has decreased and that the value of a 4 point victory has increased.

I've been using similar variation changes to the data you've posted for the past 12 years. The point of my previous post was to explain what the points mean and how they're derived using historical data rather than debate whether the data is still accurate. I'm perfectly willing to concede that old data doesn't fit modern changes to the game.
 

FLSeahawk

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I'm referencing old betting and website data from about 12 years ago. You are quoting newer data, but perhaps you are misinterpreting it. The probability of a 1 point game is about 4.3%, but that's for both teams combined. The probabliity of the favourite winning by 1 point would be a little above 2.15% and the underdog would be a little below it. It's a similar story with other points values. There are recency changes due to the reduced overtime period and the introduction of the 2 point conversion. I don't doubt that the probability of a 3 point victory has decreased and that the value of a 4 point victory has increased.

I've been using similar variation changes to the data you've posted for the past 12 years. The point of my previous post was to explain what the points mean and how they're derived using historical data rather than debate whether the data is still accurate. I'm perfectly willing to concede that old data doesn't fit modern changes to the game.
I got you. Yeah I misinterpreted your data and accounted for both teams instead of just for the favorite
 

MontanaHawk05

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It's both a division game and a Week 1 game. It's hard to be less predictive of overall season performance than that.
 

94Smith

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It's both a division game and a Week 1 game. It's hard to be less predictive of overall season performance than that.
playoffs aren't made in September. The nfl history has many hot starts that fizzled out. Also the 49ers are a very young team on defense with a couple of key pieces on the offense that are due to show up in 6 weeks. Just look at last year, the game at Levis in October was the 4-5 Seahawks vs the 5-4 49ers. 49ers went 1-7 from there, Seahawks went 6-2
 

kidhawk

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playoffs aren't made in September. The nfl history has many hot starts that fizzled out. Also the 49ers are a very young team on defense with a couple of key pieces on the offense that are due to show up in 6 weeks. Just look at last year, the game at Levis in October was the 4-5 Seahawks vs the 5-4 49ers. 49ers went 1-7 from there, Seahawks went 6-2

I agree that the first game does not predict out the season consistently but how many times have teams sat out due to one game from early in the season that they wish they had back? This could well be that one game for either team do it’s a big game.
 

FLSeahawk

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I agree that the first game does not predict out the season consistently but how many times have teams sat out due to one game from early in the season that they wish they had back? This could well be that one game for either team do it’s a big game.
Giants game last year 🤬
 

Jerhawk

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Where’s the game prediction thread? I want to make more amazing predictions
 
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AROS

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Kyle Brandt from Good Morning Football on NFL Network

And it’s a big deal because I’ve been watching GMFB for years and let me just say that Kyle has never been much of a Seahawks supporter per se. It’s a good sign because he knows football and he knows when a team is trending in the right direction regardless of how much national love they are getting.
 

DeSeahawk

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Come on toff. Win by 2 touchdowns? This game is going down to the wire. With the Hawks on the winning end.
And you know how much I despise that team.
Gotta agree here. I think it's going to be a tight game. Just cuz I hate them doesn't mean they aren't still a good team. I'm thinking 23 - 20 , Hawks take it on a late field goal
 

Trackhawk

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The points differential is a function determined by win probability. There is about a 2.5% the game ends up with a 1 point margin of victory. The chance of a 2 point victory is about 2.0% . There's between 8.5 and 9.3% of a 3 point victory. Obviously there's a slightly bigger chance of the favourite winning by any of these margins than the underdog. The probabilities are also altered by the number of points expected to be scored in a game. If the game is more likely to be low scoring the probability of a narrow victory is increased. All the 49ers -2.5 line means is the 49ers are considered to be a 54.7% chance with the Seahawks a 45.3% chance...give or take. If the 49ers were a 52.6% favourite the line would be -1.5. If the 49ers were a 63.7% chance the line would be -3.5.

Just remember that betting handicap points are not equal in value. They don't imply that a team will win by a specific margin or that a team is better by that specific margin. 3 is the biggest number and 7 is the 2nd biggest number. 6 & 10 are the other big 2 numbers. Everything else is pretty small.
How do odds come into play? While the line has held pretty constant, I've seen the odds move down from +330 to +110 on the total season wins line. I was going to put $100 on the over, until I saw that the odds had dropped to +130, then +110 last time I checked.
 

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