Going for 2
Update: Apparently, it seems, I am completely wrong about this, and that it is well established that a team should go for two earlier. Via Twitter, @bdoc87 points to the book “Mathletics” where they suggest going to two in this situation as early as the second quarter. There is also this chart, which says that you should go for two at any point in the second half if you are down 9 after scoring a touchdown.
Here is an article by Chase Stuart from www.footballperspective.com with the title “Trailing by 15 in the middle of the 4th quarter, teams are foolish to not go for 2 after touchdowns”. They are arguing, as stated in the title of the article, that if a team is down by 15 in the middle of the final quarter and they score a touchdown (cutting the lead to 9), that they should go for two in an attempt to cut the lead to 7 rather than take the extra point and cut the lead to 8. This is a fair argument and the author may well be correct, but they seem to offer absolutely no evidence that this is the correct decision. For instance, the author states:
If you are going to convert the 2-point attempt, it doesn’t matter all that much whether you go for it early or late. If you’re going to miss it, going for it earlier significantly improves your odds of pulling off a miraculous comeback, precisely because you’re [sic] got almost no chance if you miss it late.
The author first notes that it doesn’t really matter whether you go for the 2 points early or late if you are going to convert it. Sure fine, I’ll agree with that. But then in the next sentence argues that “going for it earlier significantly improves your odds of pulling off a miraculous comeback”. Is this true? It may well be, but I see nothing in the article that even remotely supports this point. It seems to just be stated as fact with no supporting evidence. I am gonna need more proof than this. Ideally, one would look to collect actual data on this, and try to compare the two decisions. However, it seems like football coaches almost always go for one, so a simulation study may be better here. Make some assumptions, develop a model for a football game, and simulate this scenario say 10000 times going for the extra point and 10000 times going for 2. Then you can estimate the probabilities of a win and say a team will win X percent of the time going for 1 and Y percent of the time going to 2. I suspect there probably really isn’t much of a difference at all, but I have no evidence for or against this point. It’s simply my opinion. It looks to me like this entire article is stating a hypothesis (going for two is better than going for one), and that it is the authors opinion that going for two is better than going for one. However, they seem to offer no evidence at all in support of their claims. Although maybe I am missing something.