Thursday, September 11, 2014

Predicting the Bears Defense

Last Sunday's loss to the Bills stung. More than anything, I was bummed to see so little of Jared Allen, Lance Briggs, and Charles Tillman -- the veterans who I expected would at least perform up to recent standards. (Of course, of those three, Tillman not having any big plays could very well be just him having a solid game and pushing plays towards the other DBs.)

As a whole, though, I am worried like most Bears fans that the defense is poised once again to lead the league yards allowed per play and likewise finish as or near the bottom in points allowed per game. In 2013, only the Vikings were worse than the Bears in preventing scores, and they were worse by only 2 points. Ouch.

But here's a fun fact: Almost all of point scoring can be captured by two basic defensive stats.
  1. Y/P: Yards per play, or the total yards allowed by the defense divided by the number of defensive plays.
  2. Start: The average starting position for the defense -- i.e. where the defense takes over after the most recent Jay Cutler interception.
Given 2013's numbers, these three statistics explain almost all of the variations in points allowed per game (82% or 0.82 R-squared). And if we run a linear regression on these items, we get a formula like this:

Points/Game = (6.72 * Y/P) + (1.12 * Start)
Using this really basic formula, we can make primitive predictions about the Bears defense (Note: There is no shortage of complex and more reliable predictions on Advanced Football Analytics and Football Outsiders; go there for those aims).

So far in 2014, the Bears have allowed 6.4 yards per play and have had to start on the 32.9 yard line. What's fun about these stats is that they represent components controlled by the defense (Y/P) and the offense and special teams (Start).

Given they continue their previous performance, the Bears defense will allow something between 30 and 42 points per game in a typical Sunday. That's not good.

But let's say the offense is what we thought it is, and the average starting position moves to a league average 28-yard line. The defense then improves to a 25 to 35 range -- much better, especially if the offense is scoring more than 20 points. Looking at it from the other direction: What if the field position issue doesn't resolve, but the defense manages to reduces the yard-per-play issue? With a league average 5.4 Y/P, the Bears would give up somewhere between 24 and 34 points per game -- almost the same impact as a league average starting position.

This leads me to suspect this is not just a defense problem. The Bears offense must sustain drives and give the Bears defense a better chance. Both sides (and special teams too) appear to blame so far.

"Lion Chicago Bears Helmet" by Original uploader was ShadowJester07 at en.wikipedia - Transferred from en.wikipedia; transfer was stated to be made by User:Poromiami. Licensed under CC BY-SA 2.0 via Wikimedia Commons.

Friday, September 5, 2014

Luis Valbuena Should be a Starter in 2015

Look, I was the hardest sell on 3B Luis Valbuena since day one. When the Cubs got him in 2012, they said they liked his defense, but all the data we had at the time -- which was just 806 PA -- said he was bad in both offense and defense:


But now, with Anthony Rizzo and Starlin Castro out of the lineup, Valbuena is hitting cleanup. And he's not just hitting cleanup because the lineup is broken (see: Javier Baez and Jorge Soler); he's hitting cleanup because he's hitting well. And he could very well continue to do as much.

Friday, August 22, 2014

The Cubs and Pitchers


Yesterday, Dave Cameron kinda said what we're all starting to think:

Besides Jake Arrieta — who continues to pitch like a legitimate front-line guy — the Cubs rotation might not be full of potential aces, but there’s nothing wrong with having one good starter and four decent guys.

I have never hidden my affinity for NPB and Cuban exports (those league feel so exotic and unknown!), and so I accept the accusation I might be overly optimistic on Tsuyoshi Wada. That being said, was good -- if not great -- in Japan, and now even Dave Cameron lists him among the positive surprises in the Cubs pitching universe.

Add to that: Jason Hammel, Scott Feldman, and Paul Maholm. Since 2012, the front office has managed to add at least one low-risk, medium-reward starting pitcher to each rotation. If nothing else, this means they've learned to how to make smart gambles on pitching (because, let's observe here, free agent pitchers are gambles, and there is no guarantee the next Jason Hammel they sign will do anything but plop a big ol' turd on the staff ERA).

So do the Cubs need Jon Lester? No, but that'd be huge if they got him. Do they need to trade Javier Baez or Jorge Soler? Nope. Not at all, unless they're getting a whopping doozy in return.

In fact, given a few prudent acquisitions here or there, I think we could be seeing a really good team on the northside. World Series good? Maybe not. A winning team though?

Definitely next year.

Friday, March 28, 2014

In Praise of Jose Quintana

I'm glad to see Jose Quintana getting some love from Jeff. Moreover, Rick Hahn is building a solid team here. He's got Quintana locked down for a bevy of seasons at a very reasonable discount. He's turned some vets into prospects and added a sexy international free agent in the form of Jose Abreu.

But let's look at Quintana because he's the most surprising part to me. He's this lefty who kind of signed out of nowhere (or, rather, out of a dark cloud of PED murkiness) and then, just as the White Sox farm league was earning Minor League Razzies, he appears to help a White Sox rotation in desperate need of help.

Look at him in comparison to some other Chicago hurlers:


Source: FanGraphs -- Jeff Samardzija, John Danks, Travis Wood

I have him on my Scoresheet roster this year, and I look forward to much of this in 2014:

Tuesday, March 18, 2014

The Hope of Tsuyoshi Wada

So long-time NPB ace Tsuyoshi Wada still has an outside shot at the fifth rotation spot for the Cubs. I have a penchant for Wada's type of player -- a foreign talent, late-ish in his career, fighting against long odds. Here's a taste of his statistics from Japan:


Year Age Tm IP ERA- FIP-
2003 22 Daiei 189.0 73 83
2004 23 Daiei 128.1 93 99
2005 24 Daiei 181.2 81 83
2006 25 Softbank 163.1 82 95
2007 26 Softbank 182.0 79 83
2008 27 Softbank 162.0 93 84
2009 28 Softbank 84.1 101 97
2010 29 Softbank 169.1 80 77
2011 30 Softbank 184.2 51 77
9 Seasons 1444.2 79 85

In my article in the 2014 Hardball Times Annual, I proposed the "10- and 20- rule of thumb" for players transitioning from the NPB to the MLB. In short: We can expect to add 10 points to a pitcher's FIP- and 20 points to a hitter's wOBA+.

Monday, March 17, 2014

The Keys to Baseball Success, as Demonstrated by the Rays

Will sent me this drawing today. It reminds me of something Dave Cameron, friend and boss, once said to me. In essence it was this: The cat's out of the bag for most advanced analytical teams. The process for creating a winning team is basically a known process: Invest in scouting, invest in international talent (especially amateur international talent), and extend your own superstars.

Friday, July 5, 2013

De-Lucker X: Buy Navarro, Sell Machado

The De-Lucker X needed a new home, and I've decided to give it a couch here at Cubs Stats. The following article was written for a broader audience, so pardon the limited Cubs-slant.

Players who began the season as starters are losing playing time; bench players are earning playing time; rookies are flopping and popping. It's the 2013 MLB season midpoint.

For a little over a year now, I have been crunching a sort of FIP for hitters -- the De-Lucker X -- that adjusts a player's wOBA based on their periphery stats. Now, behold!, the results from the first half are in! And if xBABIP can be fully, blindly trusted (and it can't), then it's time to bench Manny Machado before things get worse. Just kidding. I don't things will ever get that bad for Machado.