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Dataset: Ten Years of NFL Plays Analyzed, Visualized, Quizzified

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Re: Dataset: Ten Years of NFL Plays Analyzed, Visualized, Quizzified

#31

Post by JackFr »

socrates1998 wrote: post #24

This sounds really good and NFL teams would definitely want something like this, but even coaches would wary about using mostly data. For example, let's say you are the coach of the Patriots and you have been running the ball very successfully the past few games, even winning games because of your running game. And it's 4th down and 2 yards to go against the Broncos. The data says, run the ball. Especially since you…

Additionally, it could be that the statistics show a result that is an artifact of coaches decisions. If a particular decision is chosen by the pro coaches extremely rarely, but has a moderately better expected result, it could be that the typical expected result is very poor, but the only times coaches make the decision is when they observe a decisive matchup or a special situation -- making it appear statistically like that decision is the better one. (Like looking at basketball shooting percentages, and wondering why centers don't take all the shots given how high their FG%s are.)

Re: Dataset: Ten Years of NFL Plays Analyzed, Visualized, Quizzified

#32

Post by potench »

burntsushi wrote: post #5

If you're willing to limit yourself to the last five years, you can avoid the pain of parsing those free-form text descriptions with nflgame[1] or nfldb[2]. Disclaimer: I am the author of those tools. We've been slowly building up a small community of people using it. In fact, I'm currently in a small fantasy playoff league that's running off nflgame. They also include live updates while games are playing. I'd be cur…

I recently joined nfl.com as a FE dev; I see a lot of 404s on Game Center data feeds. The feeds are being requested past the end of the data (the feed tells you where to look for new data until last feed returns 200 with no data - beyond that it's a 404). Not sure how to reduce the 404s, suppose we could document the feeds and make them openly available. Hmm.

I like finding projects in the wild that do creative things with nfl.com data. This guy is building an Arduino Fantasy Football trophy: https://github.com/sambrenner/future-trophy And this person built an OSX app using score strip XML for current scores: https://github.com/kchau/NFL-Menu

Re: Dataset: Ten Years of NFL Plays Analyzed, Visualized, Quizzified

#33

Post by jonwachob91 »

burntsushi wrote: post #5

If you're willing to limit yourself to the last five years, you can avoid the pain of parsing those free-form text descriptions with nflgame[1] or nfldb[2]. Disclaimer: I am the author of those tools. We've been slowly building up a small community of people using it. In fact, I'm currently in a small fantasy playoff league that's running off nflgame. They also include live updates while games are playing. I'd be cur…

Awesome!!! Thank you for creating this!

Re: Dataset: Ten Years of NFL Plays Analyzed, Visualized, Quizzified

#34

Post by burntsushi »

potench wrote: post #32
burntsushi wrote: post #5

If you're willing to limit yourself to the last five years, you can avoid the pain of parsing those free-form text descriptions with nflgame[1] or nfldb[2]. Disclaimer: I am the author of those tools. We've been slowly building up a small community of people using it. In fact, I'm currently in a small fantasy playoff league that's running off nflgame. They also include live updates while games are playing. I'd be cur…

I recently joined nfl.com as a FE dev; I see a lot of 404s on Game Center data feeds. The feeds are being requested past the end of the data (the feed tells you where to look for new data until last feed returns 200 with no data - beyond that it's a 404). Not sure how to reduce the 404s, suppose we could document the feeds and make them openly available. Hmm. I like finding projects in the wild that do creative thing…

> I recently joined nfl.com as a FE dev

Wow, nice! Tell me, how many different unique identifiers to you have for each player/game? :P (Elias id, GSIS id, profile id, ...)

> I see a lot of 404s on Game Center data feeds.

Hmm, I'm not sure what you mean? It seems like the URL stays the same: http://www.nfl.com/liveupdate/game-center/2012080953/2012080...

> Not sure how to reduce the 404s, suppose we could document the feeds and make them openly available.

Yeah, that'd be great! I had figured that you guys kept quiet about them purposefully.

One of the things that has bit me is that the JSON feeds at the URL above only exist back to 2009. I haven't been able to discover a similar feed for older games. Any ideas? :-)

Those projects are pretty neat, btw. The trophy one is really cool.

Re: Dataset: Ten Years of NFL Plays Analyzed, Visualized, Quizzified

#35

Post by socrates1998 »

JackFr wrote: post #31
socrates1998 wrote: post #24

This sounds really good and NFL teams would definitely want something like this, but even coaches would wary about using mostly data. For example, let's say you are the coach of the Patriots and you have been running the ball very successfully the past few games, even winning games because of your running game. And it's 4th down and 2 yards to go against the Broncos. The data says, run the ball. Especially since you…

Additionally, it could be that the statistics show a result that is an artifact of coaches decisions. If a particular decision is chosen by the pro coaches extremely rarely, but has a moderately better expected result, it could be that the typical expected result is very poor, but the only times coaches make the decision is when they observe a decisive matchup or a special situation -- making it appear statistically…

That is an excellent point.

Coaches do what they think will be successful. If they can't run the ball well, then they don't run the ball, skewing the data.

Also, tendencies change from week to week. You really need a deep understanding of football to get the right, correct data for that week.

This is why data hasn't dominated football, you need to have tons of knowledge before anything else.

Re: Dataset: Ten Years of NFL Plays Analyzed, Visualized, Quizzified

#36

Post by cubecul »

glaugh wrote: post #4
cubecul wrote: post #2

"You got 2 out of 5 answers correct. When you try this quiz with a sorry quiz-taker like you, that’s the result you’re going to get." Sassy. Jesus Christ.

OP here Made the message a bit friendlier for future folks, thanks for the feedback :)

Haha it was totally fine and funny, just a little surprising. Didn't expect to see something with so much attitude in a page like that.

Re: Dataset: Ten Years of NFL Plays Analyzed, Visualized, Quizzified

#37

Post by market_hacker »

I think there may be a problem with this kind of analysis - it seems to me that the "riskier" plays (2 point conversion, going for it, etc.) - are more likely attempted when coaches think they will work - not randomly. To really do a fair analysis of expectancy you would need trials where the play selection is chosen randomly. Anyone else agree with me?

Re: Dataset: Ten Years of NFL Plays Analyzed, Visualized, Quizzified

#38

Post by centralwinger »

JackFr wrote: post #31
socrates1998 wrote: post #24

This sounds really good and NFL teams would definitely want something like this, but even coaches would wary about using mostly data. For example, let's say you are the coach of the Patriots and you have been running the ball very successfully the past few games, even winning games because of your running game. And it's 4th down and 2 yards to go against the Broncos. The data says, run the ball. Especially since you…

Additionally, it could be that the statistics show a result that is an artifact of coaches decisions. If a particular decision is chosen by the pro coaches extremely rarely, but has a moderately better expected result, it could be that the typical expected result is very poor, but the only times coaches make the decision is when they observe a decisive matchup or a special situation -- making it appear statistically…

I think it's more than "additionally", your point is the major point.

It's difficult, but data can in fact control for matchups and schemes.

Re: Dataset: Ten Years of NFL Plays Analyzed, Visualized, Quizzified

#39

Post by the_watcher »

socrates1998 wrote: post #24

This sounds really good and NFL teams would definitely want something like this, but even coaches would wary about using mostly data. For example, let's say you are the coach of the Patriots and you have been running the ball very successfully the past few games, even winning games because of your running game. And it's 4th down and 2 yards to go against the Broncos. The data says, run the ball. Especially since you…

The point of all the data is to give coaches more objective information. To use your example: The data says run the ball. The stud defensive tackle has just started playing really well. Here's the beauty of the way this data can be presented: While there is a way to present it as "expected points," you can also present it as "likelihood of a given result."

In this case, the positive outcomes for the offense are a first down (or score, which would also be a first down). If the data says you will pick up a first down 51% of the time and you know the Broncos tackle has recently begun playing well, you adjust down for it, and likely decide not to run (and no analytics guy will fault you for it). If the data says you'll pick up a first down 85% of the time, you need a better reason to justify not going for it (is this new tackle the greatest of all time? Or just an upgrade on what they had?). Data is not best used as a replacement for a coach. It is best used to give a coach the likelihood of a given event occurring, and then let the coaches knowledge of matchups, injuries, and personnel issues adjust that likelihood up or down.

Re: Dataset: Ten Years of NFL Plays Analyzed, Visualized, Quizzified

#40

Post by the_watcher »

socrates1998 wrote: post #35
JackFr wrote: post #31

Earlier quoted context omitted.

Additionally, it could be that the statistics show a result that is an artifact of coaches decisions. If a particular decision is chosen by the pro coaches extremely rarely, but has a moderately better expected result, it could be that the typical expected result is very poor, but the only times coaches make the decision is when they observe a decisive matchup or a special situation -- making it appear statistically…

That is an excellent point. Coaches do what they think will be successful. If they can't run the ball well, then they don't run the ball, skewing the data. Also, tendencies change from week to week. You really need a deep understanding of football to get the right, correct data for that week. This is why data hasn't dominated football, you need to have tons of knowledge before anything else.

The best use of data is to give coaches a high level picture of what the likely result of a given play call will be (trusting sample size to even it out). You hire a coach to then adjust for those other things. However, if the data says that 99% of the time a given play call will have a specific result, coaches shouldn't try to be the exception (unless the game situation demands it). There is a happy medium here. The Rays have figured it out pretty well with Joe Maddon, the NFL will get there too. No one thinks a machine should call all the plays (yet). We just think machine learning and big data should be leaned on as tools the same way that film is. Don't forget, Bill Sharman was considered a nut for watching film in the 1980s. Imagine coaching without now.
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