11 ms·

Should you go for 2 down 8?

33 points by alexmolas 3y ago

ranprieur 3y ago
A psychological factor he doesn't mention: A lot of players, if they absolutely need to make a play to not lose the game, will dig deeper and play better. If the game is not on the line right now, they won't play as well.
brodouevencode 3y ago
This is something that coaches and players know to be true intuitively and have to suffer the derangement from the stands and from online.
zeroonetwothree 3y ago
This argument is iffy because it seems to also equally well apply to being down 8 in the first quarter yet no one would go for 2 in that scenario.
- deschutes 3y ago
  It's not the same. You expect that the other team will score with so many possessions remaining. And when they do, they will be able to capitalize on the information gained from your 2 point attempt. In terms of expected value, 2 point conversion attempts are roughly par with extra points, though with so few scoring events in the game you would expect large variance. So outside of scenarios where it is pure upside (1 point doesn't matter without many more scoring events) teams will opt for the lower variance outcome. This matches practice pretty well IME.
  - dgfitz 3y ago
    > It's not the same. You expect that the other team will score with so many possessions remaining. If Baltimore special teams doesn't let a punt return TD happen, Houston had one FG to their name... the entire game. I don't expect a team will always score, absolutely not a team playing against one of the best defenses in football history. So, I respectfully disagree with your thesis. :)
    - wavemode 3y ago
      You may not personally expect it, sitting on the sidelines. But the people on the field do have to expect it. They can't make sound strategic decisions while operating under an assumption that the opposing team will never score a touchdown.
- m3kw9 3y ago
  The issue is that a coach going for 2 in the first quarter and lose because of it will look very bad and the media will always look at those and ask why you didn’t go for easy 1. Coaches aren’t gonna put their job on the line to look cute
- DiggyJohnson 3y ago
  Well it could very well be a slight inefficiency as a result of tradition or inertia or whatever. I also suspect that the probability of converting for 2 goes down with each subsequent attempt. You can expect teams to have a few plays installed specifically for critical 2PC attempts, and you may not want to burn those plays for marginal gain early in the game.
cp9 3y ago
sorry but none of this makes any sense. these are the assumptions they are attempting to debunk: - All 2-point conversions are equally likely to succeed. I have seen no evidence that all 2-point conversions *aren't* equally likely to succeed, and even if they were two bites at that apple gives you better odds than just one - You will stop the other team from scoring. regardless of whether you choose to go for it or kick the XP, you still have to stop your opponent on their subsequent drive. if they do so much as kick a FG it's game over already, so it doesn't matter. - You will get a touchdown on the subsequent drive. you have to score a TD or the debate doesn't matter so it's irrelevant to this argument - The clock expires after that. again we have to assume we are preventing the opponent from scoring any additional points because the debate makes no sense without that caveat - There are even odds of winning in overtime. getting to OT in this scenario is the fallback, while it's the best outcome of just kicking the XP twice in a row
- cp9 3y ago
  > even if they were two bites at that apple gives you better odds than just one (assuming you want to win in regulation which presumably you do because OT is inherent chaotic) > getting to OT in this scenario is the fallback I meant to say "likely fallback"
- bluedino 3y ago
  > I have seen no evidence that all 2-point conversions aren't equally likely to succeed Pass plays are less likely to convert than run plays. The conversion rates aren't even equal between teams. https://www.teamrankings.com/nfl/stat/two-point-conversion-pct https://www.teamrankings.com/nfl/stat/two-point-conversion-p...
  - aidenn0 3y ago
    Surely implicit in the statement is "all 2-point conversions in the 4th quarter by the same team" since we are comparing 3 possible 2-point conversions in the 4th quarter by the same team. (2pt conversion when down by 8, 2pt conversion when down by 2, 2pt conversion when down by 1).
  - 3y ago
grraaaaahhh 3y ago
Doesn't this article basically show the exact opposite of what it's claiming? It cites simulation data showing that going for 2 here only increases the chances of winning by an absolute 1.7% and uses that to claim that that's a small increase, but it's actually not. The winning percentage of kicking for an extra point is already at 11.2%, increasing that by 1.7 is quite large (and is actually a larger increase than the relative 12% increase the article says is ludicrous).
raldi 3y ago
Bold karma move, submitting this to HN right after the United States went to sleep.
CameronBanga 3y ago
Shouldn't this be "Go for 2 when down 14"? If you're down 8, with limited time remaining, you should always go for 2 to tie the game, instead of still being down by 1. You'd still need a field goal to take the lead, and that would still be the case if you miss the 2pt conversion.
- cp9 3y ago
  the context is "yes, you were down by 14, but your team just lined up and scored a TD on the last play. you have to make the decision whether to kick the XP or go for 2. since you just scored 6, you are now down 8" it is confusing because the conversation is taking place after you just scored
mminer237 3y ago
I don't really understand the disagreement. The main disagreement seems to be that others say it increases the win probability by 12% assuming you score the needed touchdown afterwards, and the author says that it's not really 12% because there's a 90% chance you won't score the touchdown? On its face, I tend to agree with the others that that's irrelevant. In the linked blog post with the actual statistics in it, she argues that it only increases your chance from 11.2% to 12.9%, so it only really increases your chances by 1.7%. But that just seems to be dishonestly reframing the numbers so people think a 1.7% absolute increase is nothing. But that really is a 15% increase in win chance. It sounds like the data says the 2 points is even better than its proponents claim? His only other argument is that failing the conversion psychs a team out, which I respect, but that's still just a bare assertion. I don't know why you'd get so mad at statistics for ignoring your feelings. People are complex and absent data otherwise, I would think it just as plausible that the added pressure and imminentness increases performance.
- fluoridation 3y ago
  >But that really is a 15% increase in win chance. No, that's dishonest. Probabilities are already ratios between magnitudes (desirable vs. undesirable outcomes), so when comparing them you should be subtracting them, not dividing them. A relative increase in probability of 15% doesn't tell you anything if you don't already know the base probability. Also, why go for the 15%? You could also say that the loss probability is reduced by 2%. But I guess you don't get a nice juicy number that way.
  - peeters 3y ago
    If you are given the option of taking one lottery ticket or two lottery tickets, is it dishonest to say that taking two lottery tickets would increase your odds of winning by 100% over taking just one? Do you need to know the odds of a single ticket winning to make that claim? I think you're using a restrictive and non-standard interpretation of percentages. They can be used to convey overall probability, but also a change in probability. Only allowing one usage is just a communication deficit.
m3kw9 3y ago
Depends on the time left and the calibre of your qb and receivers if you have enough time to drive down to kicking range if you fail going for 2. The opposing team may have a great run game and will run out the clock. Usually with lots of time left you always go for 1 as that’s a high percentage shot and 2 is low
- graywh 3y ago
  kicking range would be meaningless in this situation if you fail, you still trail by 8
  - m3kw9 3y ago
    I assume if you trail by 8 and you scored a TD, you’d either tie or trail by 2
    - addaon 3y ago
      > I assume if you trail by 8 and you scored a TD, you’d either tie or trail by 2 Or trail by 4, if you really botch it up.
      - aidenn0 3y ago
        I can't keep track of the rules; can you return a blocked 1-pt attempt for points?
        addaon 3y ago
        Yep, two points, as of... 2015 or so?
    - peeters 3y ago
      The context is "should I go for the 2-pt conversion?" When you're making that decision, you've already received 6 points for scoring the corresponding touchdown. The scenario presented is that you were down by 14, then you scored a touchdown to be down 8, and now have to decide whether to kick the PAT or go for 2 points. That's why it's correct to say "when you're down by 8". They're talking about a scenario where you'll still have to score another TD.
allturtles 3y ago
> ...the Bucs would eventually lose because Coach Todd Bowles forgot to use his final timeout. Is this intended to be tongue-in-cheek? Reading such a statement (which logically implies that "if Todd Bowles had used his final timeout, the Bucs would have won") in a post about how other people's reasoning is insufficiently rigorous is off-putting.
- thehappypm 3y ago
  No, it's not tongue-in-cheek but it's oversimplifying the situation. The Bucs might have been able to win if they had used their last timeout. It sounds like the coaching staff were morons and couldn't count to 3. However, they were given an extra timeout due to an unusual situation, and it seems that the coaches were either unaware of the extra timeout or forgot about it.
  - graywh 3y ago
    if the Bucs use that timeout, the Lions could still get the clock to around 11 seconds before needing to punt
  - mason55 3y ago
    It's unclear. The Lions also weren't running down the play clock. Possibly everyone just accepted that the game was over and the Lions didn't run down the play clock and the Bucs didn't use their time out. Or Bowles mentally marked the game as over and then didn't notice the Lions messed up with the play clock.
  - deleted 3y ago
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- dgfitz 3y ago
  > So, the game clock showed 36 seconds remaining when Goff took a knee for the third and final time and the hugs and the handshakes, the celebrations and condolences, commenced. > Now, had Bowles used his last timeout, maybe the Lions decide to punt instead of attempting a long field goal. But Bowles surmised a kick through the uprights would have ensued. Basically, he would have had 36 seconds because of the clock mismanagement on the side of Detroit. Even with 0 timeouts, you can knock out 4-5 solid plays, which is a lot more than 0 solid plays. He goofed up. https://apnews.com/article/lions-buccaneers-bowles-campbell-mayfield-goff-77600943664e6925daafb6acaed64288 https://apnews.com/article/lions-buccaneers-bowles-campbell-...
deleted 3y ago
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gok 3y ago
> Under these assumptions, Laura uses a computational technique called Dynamic Programming to evaluate all possible scenarios in the game tree. Once you factor in this more complex set of possibilities, the “62.5%” mirage disappears. Laura finds that if you are down by 2 TDs, G42D8 increases your probability of winning by less than 1%. This is misreading the original source [1]. The <1% figure applies when you have not already gotten the first TD. [1] https://punkrockor.com/2019/11/15/when-should-a-football-team-attempt-a-two-point-conversion-instead-of-an-extra-point-a-dynamic-programming-approach/ https://punkrockor.com/2019/11/15/when-should-a-football-tea...
- aidenn0 3y ago
  > We can examine the decision in more detail. When down by 8 with four possessions to go (which matches up with when Carolina went for a two point conversion), a team has one of two choices: Down by 8 and facing a conversion opportunity means you were down by 14 and just scored a touchdown (6 points). It's more that 1 percentage point change (1.7%) not less (and as others have pointed out, it increases your win probability by about 15%), so there is still a misreading.
contravariant 3y ago
This article isn't the easiest to read when you've got no clue what any of the following mean: - go for 2 - down 8 - convert Or which sport they come from for that matter. Some of these I could guess, but 'conversion' is a tricky one.
- mminer237 3y ago
  In American football, getting the ball to the other side of the field is a touchdown and worth 6 points. Afterwards, you have the option of kicking the ball through the posts for 1 extra point (which is almost guaranteed) or trying to run the ball into the end zone in one attempt for 2 extra points. If you make a touchdown but you still have 8 fewer points than the other team, you can either take the 1 point and hope to score again then get 1 more point again to tie, or you can try for 2 points and hope to score again and then either take the 1 point for the win if you make the first 2 points or try the 2 points again then to tie it up. A "conversion" is scoring either form of extra points.
peeters 3y ago
This is a very long article which seems to just reveal the author doesn't understand the difference between percentages and percentage points. 50% to 62.5% in the simplified calculation is a 25% improvement, not a 12.5% improvement. It's a 25% improvement on already low odds (after all, nobody is actually saying that it's 100% probability that your D will stop the next drive and then you will score another touchdown. It's just assuming that those things have to happen either way so the odds cancel out, and this is looking at win probability assuming that those things happen). Laura's calculations, for a similar scenario (4 possessions remaining), projects the overall probability of winning going from 11.2% -> 12.9%, which is a 15% improvement, roughly the same order of magnitude as the simplified example. I don't have the exact breakdown for a two-possession scenario, but in her slideshow she says this, which seems to be what the author is citing: > If down by ...16 (before the 6 TD points), the strategy improves the win probability by <1%. But I am convinced she is talking about absolute percentage points here (e.g. 10% to 10.9%), not a <1% change (e.g. 10% to 10.09%). Why? Because the slide has this before it: > Rationale: if you are down by 15, you have to score two touchdowns while keeping your opponent from scoring She is demonstrating that it's not a silver bullet given it's exceedingly unlikely you will win anyway.
croes 3y ago
If the winning chance is higher then yes. I don't understand the point of the article. If G42D8 increases the chance of winning it's the way to go. Doesn't matter how much the increase is as long it's an increase. What the probability of losing if you don't G42D8?
bombcar 3y ago
If you're interested in this kind of thing, I highly recommend these books: Football Clock Management - https://johntreed.com/collections/football-coaching-books/products/football-clock-management-5th-edition-book-by-john-t-reed https://johntreed.com/collections/football-coaching-books/pr... The Contrarian Edge for Football Offense - https://johntreed.com/collections/football-coaching-books/products/the-contrarian-edge-for-football-offense-2nd-edition-book-by-john-t-reed https://johntreed.com/collections/football-coaching-books/pr... Clock management is not just for the last minutes of the game, it is a fundamental part of the strategy for the entirety of play, starting before the game. I enjoyed them from a not-really-even-a-fan perspective, somewhat like a Moneyball type of read.
karaterobot 3y ago
What am I missing? It seems like this is based on assigning arbitrary probabilities to outcomes and calculating from there. I would assume that it was more useful to look at the outcomes of previous attempts by any team in the same situation and use that to guess how likely the outcome of this attempt is.
kristjansson 3y ago
If you have to stop 'em once and score twice, you might as well try to win too? Kicking the extra points can only lead to a tie, but going for two affords at least a chance at a win in regulation.
thehappypm 3y ago
You really do have an advantage by going for 2 first, and it's because you have gained information by doing so. The possible choices you can make for 2 PATs are: Kick, Kick Kick, Attempt Attempt, Attempt Attempt, Kick If you kick first, let's assume kicking is 100% successful, now your choices are: Kick made => Attempt Kick made => Kick again These are both rational choices; attempting gives you a 50/50 shot to win, and kicking again sends you to OT with a 50/50 chance. Now let's look at if you attempt first. Attempt made => Kick Attempt made => Attempt again (irrational!) Attempt missed => Kick (irrational!) Attempt missed => Attempt again Some of these are irrational! If you made the conversion, just kick it to win by 1! This information gain helps you eliminate irrational choices, whereas if you kick first, no choices are eliminated for you.
mondocat 3y ago
The actual stats on the two point conversion: "About 47.5 percent of the time since 2015 — almost exactly half that of the extra-point conversion rate." The other point is you have to make the first 2-point conversion to win. You can still tie with the next attempt, but not win. That makes the odds of winning by taking the two point conversion, pre-overtime, is 47.5%. (The odds of losing is higher, because you could also miss the second attempt and not go to overtime.) So, don't go for two.

33 points by alexmolas 3y ago

A psychological factor he doesn't mention: A lot of players, if they absolutely need to make a play to not lose the game, will dig deeper and play better. If the game is not on the line right now, they won't play as well.

brodouevencode 3y ago

This is something that coaches and players know to be true intuitively and have to suffer the derangement from the stands and from online.

zeroonetwothree 3y ago

This argument is iffy because it seems to also equally well apply to being down 8 in the first quarter yet no one would go for 2 in that scenario.

deschutes 3y ago
It's not the same. You expect that the other team will score with so many possessions remaining. And when they do, they will be able to capitalize on the information gained from your 2 point attempt. In terms of expected value, 2 point conversion attempts are roughly par with extra points, though with so few scoring events in the game you would expect large variance. So outside of scenarios where it is pure upside (1 point doesn't matter without many more scoring events) teams will opt for the lower variance outcome. This matches practice pretty well IME.
- dgfitz 3y ago
  > It's not the same. You expect that the other team will score with so many possessions remaining. If Baltimore special teams doesn't let a punt return TD happen, Houston had one FG to their name... the entire game. I don't expect a team will always score, absolutely not a team playing against one of the best defenses in football history. So, I respectfully disagree with your thesis. :)
  - wavemode 3y ago
    You may not personally expect it, sitting on the sidelines. But the people on the field do have to expect it. They can't make sound strategic decisions while operating under an assumption that the opposing team will never score a touchdown.
m3kw9 3y ago
The issue is that a coach going for 2 in the first quarter and lose because of it will look very bad and the media will always look at those and ask why you didn’t go for easy 1. Coaches aren’t gonna put their job on the line to look cute
DiggyJohnson 3y ago
Well it could very well be a slight inefficiency as a result of tradition or inertia or whatever. I also suspect that the probability of converting for 2 goes down with each subsequent attempt. You can expect teams to have a few plays installed specifically for critical 2PC attempts, and you may not want to burn those plays for marginal gain early in the game.

cp9 3y ago

sorry but none of this makes any sense. these are the assumptions they are attempting to debunk: - All 2-point conversions are equally likely to succeed. I have seen no evidence that all 2-point conversions *aren't* equally likely to succeed, and even if they were two bites at that apple gives you better odds than just one - You will stop the other team from scoring. regardless of whether you choose to go for it or kick the XP, you still have to stop your opponent on their subsequent drive. if they do so much as kick a FG it's game over already, so it doesn't matter. - You will get a touchdown on the subsequent drive. you have to score a TD or the debate doesn't matter so it's irrelevant to this argument - The clock expires after that. again we have to assume we are preventing the opponent from scoring any additional points because the debate makes no sense without that caveat - There are even odds of winning in overtime. getting to OT in this scenario is the fallback, while it's the best outcome of just kicking the XP twice in a row

cp9 3y ago
> even if they were two bites at that apple gives you better odds than just one (assuming you want to win in regulation which presumably you do because OT is inherent chaotic) > getting to OT in this scenario is the fallback I meant to say "likely fallback"
bluedino 3y ago
> I have seen no evidence that all 2-point conversions aren't equally likely to succeed Pass plays are less likely to convert than run plays. The conversion rates aren't even equal between teams. https://www.teamrankings.com/nfl/stat/two-point-conversion-pct https://www.teamrankings.com/nfl/stat/two-point-conversion-p...
- aidenn0 3y ago
  Surely implicit in the statement is "all 2-point conversions in the 4th quarter by the same team" since we are comparing 3 possible 2-point conversions in the 4th quarter by the same team. (2pt conversion when down by 8, 2pt conversion when down by 2, 2pt conversion when down by 1).
- 3y ago

grraaaaahhh 3y ago

Doesn't this article basically show the exact opposite of what it's claiming? It cites simulation data showing that going for 2 here only increases the chances of winning by an absolute 1.7% and uses that to claim that that's a small increase, but it's actually not. The winning percentage of kicking for an extra point is already at 11.2%, increasing that by 1.7 is quite large (and is actually a larger increase than the relative 12% increase the article says is ludicrous).

raldi 3y ago

Bold karma move, submitting this to HN right after the United States went to sleep.

CameronBanga 3y ago

Shouldn't this be "Go for 2 when down 14"? If you're down 8, with limited time remaining, you should always go for 2 to tie the game, instead of still being down by 1. You'd still need a field goal to take the lead, and that would still be the case if you miss the 2pt conversion.

cp9 3y ago
the context is "yes, you were down by 14, but your team just lined up and scored a TD on the last play. you have to make the decision whether to kick the XP or go for 2. since you just scored 6, you are now down 8" it is confusing because the conversation is taking place after you just scored

mminer237 3y ago

I don't really understand the disagreement. The main disagreement seems to be that others say it increases the win probability by 12% assuming you score the needed touchdown afterwards, and the author says that it's not really 12% because there's a 90% chance you won't score the touchdown? On its face, I tend to agree with the others that that's irrelevant. In the linked blog post with the actual statistics in it, she argues that it only increases your chance from 11.2% to 12.9%, so it only really increases your chances by 1.7%. But that just seems to be dishonestly reframing the numbers so people think a 1.7% absolute increase is nothing. But that really is a 15% increase in win chance. It sounds like the data says the 2 points is even better than its proponents claim? His only other argument is that failing the conversion psychs a team out, which I respect, but that's still just a bare assertion. I don't know why you'd get so mad at statistics for ignoring your feelings. People are complex and absent data otherwise, I would think it just as plausible that the added pressure and imminentness increases performance.

fluoridation 3y ago
>But that really is a 15% increase in win chance. No, that's dishonest. Probabilities are already ratios between magnitudes (desirable vs. undesirable outcomes), so when comparing them you should be subtracting them, not dividing them. A relative increase in probability of 15% doesn't tell you anything if you don't already know the base probability. Also, why go for the 15%? You could also say that the loss probability is reduced by 2%. But I guess you don't get a nice juicy number that way.
- peeters 3y ago
  If you are given the option of taking one lottery ticket or two lottery tickets, is it dishonest to say that taking two lottery tickets would increase your odds of winning by 100% over taking just one? Do you need to know the odds of a single ticket winning to make that claim? I think you're using a restrictive and non-standard interpretation of percentages. They can be used to convey overall probability, but also a change in probability. Only allowing one usage is just a communication deficit.

m3kw9 3y ago

Depends on the time left and the calibre of your qb and receivers if you have enough time to drive down to kicking range if you fail going for 2. The opposing team may have a great run game and will run out the clock. Usually with lots of time left you always go for 1 as that’s a high percentage shot and 2 is low

graywh 3y ago
kicking range would be meaningless in this situation if you fail, you still trail by 8
- m3kw9 3y ago
  I assume if you trail by 8 and you scored a TD, you’d either tie or trail by 2
  - addaon 3y ago
    > I assume if you trail by 8 and you scored a TD, you’d either tie or trail by 2 Or trail by 4, if you really botch it up.
    - aidenn0 3y ago
      I can't keep track of the rules; can you return a blocked 1-pt attempt for points?
      - addaon 3y ago
        Yep, two points, as of... 2015 or so?
  - peeters 3y ago
    The context is "should I go for the 2-pt conversion?" When you're making that decision, you've already received 6 points for scoring the corresponding touchdown. The scenario presented is that you were down by 14, then you scored a touchdown to be down 8, and now have to decide whether to kick the PAT or go for 2 points. That's why it's correct to say "when you're down by 8". They're talking about a scenario where you'll still have to score another TD.

allturtles 3y ago

> ...the Bucs would eventually lose because Coach Todd Bowles forgot to use his final timeout. Is this intended to be tongue-in-cheek? Reading such a statement (which logically implies that "if Todd Bowles had used his final timeout, the Bucs would have won") in a post about how other people's reasoning is insufficiently rigorous is off-putting.

thehappypm 3y ago
No, it's not tongue-in-cheek but it's oversimplifying the situation. The Bucs might have been able to win if they had used their last timeout. It sounds like the coaching staff were morons and couldn't count to 3. However, they were given an extra timeout due to an unusual situation, and it seems that the coaches were either unaware of the extra timeout or forgot about it.
- graywh 3y ago
  if the Bucs use that timeout, the Lions could still get the clock to around 11 seconds before needing to punt
- mason55 3y ago
  It's unclear. The Lions also weren't running down the play clock. Possibly everyone just accepted that the game was over and the Lions didn't run down the play clock and the Bucs didn't use their time out. Or Bowles mentally marked the game as over and then didn't notice the Lions messed up with the play clock.
- deleted 3y ago
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dgfitz 3y ago
> So, the game clock showed 36 seconds remaining when Goff took a knee for the third and final time and the hugs and the handshakes, the celebrations and condolences, commenced. > Now, had Bowles used his last timeout, maybe the Lions decide to punt instead of attempting a long field goal. But Bowles surmised a kick through the uprights would have ensued. Basically, he would have had 36 seconds because of the clock mismanagement on the side of Detroit. Even with 0 timeouts, you can knock out 4-5 solid plays, which is a lot more than 0 solid plays. He goofed up. https://apnews.com/article/lions-buccaneers-bowles-campbell-mayfield-goff-77600943664e6925daafb6acaed64288 https://apnews.com/article/lions-buccaneers-bowles-campbell-...

deleted 3y ago

[deleted]

gok 3y ago

> Under these assumptions, Laura uses a computational technique called Dynamic Programming to evaluate all possible scenarios in the game tree. Once you factor in this more complex set of possibilities, the “62.5%” mirage disappears. Laura finds that if you are down by 2 TDs, G42D8 increases your probability of winning by less than 1%. This is misreading the original source [1]. The <1% figure applies when you have not already gotten the first TD. [1] https://punkrockor.com/2019/11/15/when-should-a-football-team-attempt-a-two-point-conversion-instead-of-an-extra-point-a-dynamic-programming-approach/ https://punkrockor.com/2019/11/15/when-should-a-football-tea...

aidenn0 3y ago
> We can examine the decision in more detail. When down by 8 with four possessions to go (which matches up with when Carolina went for a two point conversion), a team has one of two choices: Down by 8 and facing a conversion opportunity means you were down by 14 and just scored a touchdown (6 points). It's more that 1 percentage point change (1.7%) not less (and as others have pointed out, it increases your win probability by about 15%), so there is still a misreading.

contravariant 3y ago

This article isn't the easiest to read when you've got no clue what any of the following mean: - go for 2 - down 8 - convert Or which sport they come from for that matter. Some of these I could guess, but 'conversion' is a tricky one.

mminer237 3y ago
In American football, getting the ball to the other side of the field is a touchdown and worth 6 points. Afterwards, you have the option of kicking the ball through the posts for 1 extra point (which is almost guaranteed) or trying to run the ball into the end zone in one attempt for 2 extra points. If you make a touchdown but you still have 8 fewer points than the other team, you can either take the 1 point and hope to score again then get 1 more point again to tie, or you can try for 2 points and hope to score again and then either take the 1 point for the win if you make the first 2 points or try the 2 points again then to tie it up. A "conversion" is scoring either form of extra points.

peeters 3y ago

This is a very long article which seems to just reveal the author doesn't understand the difference between percentages and percentage points. 50% to 62.5% in the simplified calculation is a 25% improvement, not a 12.5% improvement. It's a 25% improvement on already low odds (after all, nobody is actually saying that it's 100% probability that your D will stop the next drive and then you will score another touchdown. It's just assuming that those things have to happen either way so the odds cancel out, and this is looking at win probability assuming that those things happen). Laura's calculations, for a similar scenario (4 possessions remaining), projects the overall probability of winning going from 11.2% -> 12.9%, which is a 15% improvement, roughly the same order of magnitude as the simplified example. I don't have the exact breakdown for a two-possession scenario, but in her slideshow she says this, which seems to be what the author is citing: > If down by ...16 (before the 6 TD points), the strategy improves the win probability by <1%. But I am convinced she is talking about absolute percentage points here (e.g. 10% to 10.9%), not a <1% change (e.g. 10% to 10.09%). Why? Because the slide has this before it: > Rationale: if you are down by 15, you have to score two touchdowns while keeping your opponent from scoring She is demonstrating that it's not a silver bullet given it's exceedingly unlikely you will win anyway.

croes 3y ago

If the winning chance is higher then yes. I don't understand the point of the article. If G42D8 increases the chance of winning it's the way to go. Doesn't matter how much the increase is as long it's an increase. What the probability of losing if you don't G42D8?

bombcar 3y ago

If you're interested in this kind of thing, I highly recommend these books: Football Clock Management - https://johntreed.com/collections/football-coaching-books/products/football-clock-management-5th-edition-book-by-john-t-reed https://johntreed.com/collections/football-coaching-books/pr... The Contrarian Edge for Football Offense - https://johntreed.com/collections/football-coaching-books/products/the-contrarian-edge-for-football-offense-2nd-edition-book-by-john-t-reed https://johntreed.com/collections/football-coaching-books/pr... Clock management is not just for the last minutes of the game, it is a fundamental part of the strategy for the entirety of play, starting before the game. I enjoyed them from a not-really-even-a-fan perspective, somewhat like a Moneyball type of read.

karaterobot 3y ago

What am I missing? It seems like this is based on assigning arbitrary probabilities to outcomes and calculating from there. I would assume that it was more useful to look at the outcomes of previous attempts by any team in the same situation and use that to guess how likely the outcome of this attempt is.

kristjansson 3y ago

If you have to stop 'em once and score twice, you might as well try to win too? Kicking the extra points can only lead to a tie, but going for two affords at least a chance at a win in regulation.

thehappypm 3y ago

You really do have an advantage by going for 2 first, and it's because you have gained information by doing so. The possible choices you can make for 2 PATs are: Kick, Kick Kick, Attempt Attempt, Attempt Attempt, Kick If you kick first, let's assume kicking is 100% successful, now your choices are: Kick made => Attempt Kick made => Kick again These are both rational choices; attempting gives you a 50/50 shot to win, and kicking again sends you to OT with a 50/50 chance. Now let's look at if you attempt first. Attempt made => Kick Attempt made => Attempt again (irrational!) Attempt missed => Kick (irrational!) Attempt missed => Attempt again Some of these are irrational! If you made the conversion, just kick it to win by 1! This information gain helps you eliminate irrational choices, whereas if you kick first, no choices are eliminated for you.

mondocat 3y ago

The actual stats on the two point conversion: "About 47.5 percent of the time since 2015 — almost exactly half that of the extra-point conversion rate." The other point is you have to make the first 2-point conversion to win. You can still tie with the next attempt, but not win. That makes the odds of winning by taking the two point conversion, pre-overtime, is 47.5%. (The odds of losing is higher, because you could also miss the second attempt and not go to overtime.) So, don't go for two.