Safe Move = Less Chance of a Win (aka "You play to give yourself a chance!") - Arizona at St. Louis Week Dec 11, 2014

When the Safe Move Makes it Less Likely to Win

On Week 15 of the 2014 NFL Season, the division leading Arizona Cardinals faced off in St. Louis vs. the Rams. In the 4th quarter 6:10 remaining, with the Cardinals' defense playing very well, St. Louis faced a 4th and 1 at the Arizona 1 yard line, down 3-12. Needing a touchdown and a field goal (and assuming no more Arizona points), the "safe" move is to "take the points," and try to get a stop. Taking the points keeps you alive, going for a touchdown and failing effectively means you lose the game as time is running out. But does staying alive actually mean you have a better chance of winning the game?

The Logic

People in favor of taking the Field Goal say "you need to take the points" or "if you fail, you've lost the game. You have to stay in the game to win it!"

The counterargument of going for the touchdown is "You're on the 1 yard line now, it's easier to score a touchdown here and then try for a field goal than it is to kick the field goal now and drive the length of the field for a touchdown!"

Which one is right?

Going for Two. Washington at Atlanta December 15, 2013

Washington coach Mike Shanahan gets the opportunity go for the win in regulation and takes it, going for a 2 point conversion instead of electing to take a PAT and take his chances in Overtime.  QB Kirk Cousins misses the pass and Washington loses to the Atlanta Falcons 26-27.  Regardless of the result, was this the right decision?

The Situation

Down 20-27, Washington QB Kirk Cousins completes a TD pass to WR Santana Moss, pulling the team within 1 point.  There are 18 seconds left in the game, so whatever happens here is highly likely to be the final outcome of regulation.  Coach Shanahan decides to go for a 2 point conversion.  Was this the right move?

This is a relatively simple situation to analyze since there are only a couple of possibilities.

If Washington goes for the PAT, they will go to overtime 98% of the time historically.  That's close enough to 100% for our purposes.  In overtime, there is nominally a 50/50 chance of winning the game.

If Washington goes for the 2PAT, they will convert and win the game x% of the time and lose the game 100-x% of the time.  What is x actually?

Taking the Points, Part II - Miami vs. New England, December 15, 2013

The Miami Dolphins once again faced a "close" 4th down decision nearing halftime of the New England @ Miami tilt in week 15.  Down, 0-3, Miami decided to attempt a field goal, as color announcer Phil Simms said, "It looks like it's a whole yard short ... it's a good decision by the Dolphins [to go for the field goal].  Get on the scoreboard, Jim [Nantz], there nothing worse for a QB or coach to look up at that scoreboard and see that 0."

Was Simms right?  Is it better to kick the field goal here?

The Situation

After the 3rd down pass to Michael Egnew falls short of the line to gain, the Dolphins face 4th down and a long yard (one closer to 2 yards than 0 yards) on the New England 24 yard line with 3:34 left in the first half.  Out trots the FG team and Simms claims it's good to get the points on the board rather than to walk away with nothing.  However, the game of football doesn't care if you score points, you need to out score the opponent, and in this situation, you should maximize the number of Expected Points you're going to get.

So how do we calculate whether it was the right decision to kick the field goal or not?

The Factors

We have to look at several factors to determine whether or not attempting a field goal is the right move here.  Of course, we are simplifying some of these percentages, but if there is an obvious decision, that won't change with fine tuning of these numbers.

1) What is the chance kicker Caleb Sturgis will make the 42 yard field goal attempt?

2) What is the chance Miami will convert this 4th and 1 attempt?

3) If Miami makes the 4th and 1, what are the expected number of points they can expect from this drive?

4) When New England recovers the ball, either after a failed FG try, failed 4th down try, or after a kickoff following a Miami TD, what is their chances of scoring?