CSS Button No Image Css3Menu.com

Baseball Prospectus home
  
  
Click here to log in Click here for forgotten password Click here to subscribe

<< Previous Article
Premium Article Prospectus Hit and Run... (02/29)
<< Previous Column
BP Unfiltered: Basebal... (02/29)
Next Column >>
BP Unfiltered: Top Min... (03/01)
Next Article >>
Premium Article Bates' Dugout Motel: V... (03/01)

March 1, 2012

BP Unfiltered

PECOTA and Depth Chart Update *UPDATED*

by Rob McQuown

Sometimes, when you realize you've stepped in something malodorous, there's nothing to do but pause and deal with the situation at foot. Keep walking, and the substance will remain on your shoe, where it will begin to attract unwelcome attention. We made a similar misstep, in a proverbial sense, with some of our PECOTA projections this season. Recently, we discovered that National League pitchers were projected to be substantially worse than PECOTA’s logic intended due to a bug that slipped past our testing.

As unpleasant as removing the offending substance from your footwear can be, there’s always reason to be glad when it’s gone. In our case, that reason is the increased accuracy of our projections. While Clayton Kershaw still isn't projected to lead the league in WHIP—his past control problems still count against him, as Colin proved they should, so PECOTA isn't quite as wowed by his recent greatness as you or I might be—he is now projected to have the fifth-best ERA among qualifiers. You’ll find that virtually all other NL pitchers have seen their stats improve as well.

We’ve made one other big change that wasn't really a “bug fix” but will impact anyone who looks at the Depth Charts. For years, people have wondered why the team AVG/OBP/SLG projections weren't really in line with what teams ended up hitting, especially in the National League. The answer has always been that we've excluded pitcher hitting from these projected rate stats, while incorporating it into our team runs scored and allowed estimates. Well, we've changed our minds and added pitcher hitting to the team totals. So, sharing some of the pain I endured while writing about Astros players for BP2012, I'll inflict their projected season batting line upon everyone:

AVG/OBP/SLG (TAv): .248/.304/.371 (.243)

Considering Houston hit just .258/.311/.374 in 2011 and shipped out some major contributors (Hunter Pence and Michael Bourn, mainly—there weren’t that many major contributors to begin with), that projection seems entirely reasonable, much to the dismay of Astros fans.

Oh, and that number in parentheses? We added TAv to the slash lines while we were at it. (Before we added the pitchers in, the TAv values didn't make sense, as almost all of them were above the .260 mark.)

And for more fun with Depth Charts, there's a new "Visual Depth Chart" page, inspired by Ben Lindbergh's article on position weaknesses around the league.

We also made some other improvements in this PECOTA run that will be reflected soon on the player cards, and for now in the downloadable spreadsheet (click on “manage profile”), Depth Charts, Player Forecast Manager, Team Tracker, and the new Scoresheet Draft Aid. Among them are:

  • A downgrade to many player FRAA values, which were being calibrated against historical values and coming in a bit too high.
  • A fix for a minor bug in stolen base projections. I noticed this while writing about Nyjer Morgan for Value Picks a while back—it turns out PECOTA was over-counting steals in seasons where a player played for multiple teams, as Morgan did in 2009, and the smart readers picked up on that before I could quickly fix the problem and sweep it under the rug. (Just kidding—we'll continue to keep you posted when we change things, as we’re doing with this post.)
  • A bug fix in pitcher WARP calculations that was originally fixed during the 2011 season but wasn't propagated to the earlier PECOTA runs. It’s in there now, so some pitchers will see a change in their WARP.

Writing this sort of “confessional” isn't much fun, but we at Baseball Prospectus do think that being open about such things is only fair to you, our readers. We hope that you’ll enjoy the improvements in the stats now that the fixes are in place. Meanwhile, we're paying even closer attention to where we step.

UPDATE TO THE UPDATE: Two more quick changes to tell you about. First, we've switched from using 2011 positional adjustments to using positional adjustments generated from the projected data in the depth charts themselves. Secondly, we've changed the weights on stolen bases and caught stealings to better reflect the run environment currently. --CW

Rob McQuown is an author of Baseball Prospectus. 
Click here to see Rob's other articles. You can contact Rob by clicking here

39 comments have been left for this article. (Click to hide comments)

BP Comment Quick Links

brooklyn55

Rob ... upfrontness (gotta be a Colbert word) appreciated. The update though has dropped the Japanese pitchers, Darvish, Chen, Wada ...

Mar 01, 2012 01:12 AM
rating: 0
 
BP staff member Rob McQuown
BP staff

Yeah, they haven't shown up in spreadsheets yet. In the interest of time, we haven't fully projected these players yet, but instead, we've used portions of PECOTA to provide interim forecasts so that standings and fantasy values could be computed reasonably. Expect slight changes to them at some point in the future.

You'll find the current projections for those guys in Depth Charts and in PFM.

Mar 01, 2012 06:11 AM
 
Hoff

Wait, are the DC's for the NL pitchers accurate now?

Mar 01, 2012 05:49 AM
rating: 0
 
BP staff member Rob McQuown
BP staff

Yes, they should be fine. E.g. Kershaw has a 2.95 projected ERA.

Mar 01, 2012 05:51 AM
 
Hoff

So when was this change implemented and why haven't all the updated dates for nl pitchers changed?

Mar 01, 2012 06:52 AM
rating: 0
 
BP staff member Rob McQuown
BP staff

Update Dates on the Depth Charts are changed whenever a Depth Chart playing time adjustment is made, not when projections are altered, as every change in PT for any player impacts all the projections, as the league baseline is reset, and that has a ripple effect. Obviously, it's usually a lot less impactful than this change was, however.

The date for the spreadsheet is on http://www.baseballprospectus.com/fantasy/

Mar 01, 2012 07:04 AM
 
fieldofdreams

So should we ignore what is in BP 2012?

Mar 01, 2012 06:50 AM
rating: 4
 
BarryR

This is a very good question and I'd like to see the answer.

Mar 01, 2012 09:59 AM
rating: 1
 
Softy Electric

You don't have to ignore them; just know that online you can find "more accurate" or "truer" PECOTA projections.

Mar 01, 2012 13:20 PM
rating: 3
 
BP staff member Dave Pease
BP staff
(2)

The effect of this bug was to slightly deflate NL pitcher performance, and the projections in the book were affected by the bug.

Softy Electric is also correct, and in general projections will improve over time and the latest projections from the site will always be better than the projections in BP2012.

Mar 01, 2012 14:17 PM
 
modofacid

Rob,

I can't select players drafted during the draft to be on my team (the check box on the right side doesn't show up). Is it a Chrome issue? Or are other people having the same issue?

Mar 01, 2012 06:50 AM
rating: 0
 
BP staff member Rob McQuown
BP staff

Is this a PFM question? We test PFM using Chrome on both PC and Mac. What happens when you select them?

Mar 01, 2012 06:59 AM
 
BP staff member Rob McQuown
BP staff

Sorry, I added that last question and clicked Submit and then realized that you'd said you can't even see the boxes... Feel free to use Contact Us form to send questions about what you're trying to do and what's happening, please. I'm confused, but we'll make time to help.

If you mean the Scoresheet Draft Aid, reloading the page should remove any players who have been taken, as it polls the Scoresheet data directly.

Mar 01, 2012 07:57 AM
 
BP staff member Ben Murphy
BP staff

It sounds like perhaps you don't have the user centric inflation option turned up. It defaults to "0 (None)" and you'll need to change it to 1 or greater to have the checkbox show up to indicate which players are on your team. Also, don't change it back to zero later, or it will forget which players you told it were on your team. If that doesn't work, please contact Customer Service and we can give you more individual support. Thanks!

Mar 01, 2012 08:04 AM
 
jrmayne

Fixing things is good. As I've noted ad nauseum, I think that sticking to your guns on some of PECOTA's perceived flaws has been mistaken; finding and fixing flaws is important. There should be a mental bonus, rather than a mental penalty, for fixing things.

On this topic, I think "Colin proved they should," in regards to using older data weighted higher than other projections should read, "Colin asserted they should." If there's proof in the linked article, I didn't see it.

Mar 01, 2012 07:17 AM
rating: 4
 
Jared Cross
(694)

Little bugs like this are inevitable in a program as complex as PECOTA so no worries and good job catching it.

Mar 01, 2012 07:38 AM
rating: 3
 
Mooser

I agree. I have been eagerly awaiting this.

Mar 01, 2012 11:33 AM
rating: 0
 
evo34

ETA for 10-year projections?

Mar 01, 2012 11:47 AM
rating: 2
 
kcheaden

I'd love to see a "Visual Depth Chart" for defense only.

Mar 01, 2012 16:51 PM
rating: 0
 
BP staff member Rob McQuown
BP staff

Ask and ye shall receive.

Mar 03, 2012 09:10 AM
 
kcheaden

Awesome. Thank you.

Mar 05, 2012 14:08 PM
rating: 0
 
acardonick

Has anyone pointed out that this change seems to have reduced P strikeouts across the board? For literally every one of the pitchers I checked, SO/IP went down, in some cases by a fair amount.

Mar 01, 2012 17:20 PM
rating: 0
 
BP staff member Joe Hamrahi
BP staff

We're going to check into this. Thanks

Mar 01, 2012 18:11 PM
 
LynchMob

Was there an article posted which reviewed the 2011 PECOTA projections?

For example, what % of players exceeded their "2011 PECOTA Weighted Mean Projections"? (question: should it have been 50%?)

Another type of question I'm interested in ... what % of players which PECOTA said had a 5% chance of "Breakout" actually had a Breakout?

Thanks for PECOTA!

Mar 01, 2012 17:36 PM
rating: 3
 
BP staff member Dave Pease
BP staff
(2)

LynchMob, we do have some PECOTA results analysis that we're planning on running next week. Thanks!

Mar 01, 2012 21:38 PM
 
BP staff member Rob McQuown
BP staff

Not to split hairs too much, but it should be 50% in 50th Percentile, which is somewhat different than the Weighted Means lines, as, well, to put it simply, there's more room to go up than down.

Or, put another way, the difference between Weighted Mean and 50th Percentile is essentially the difference between statistical measures "mean" and "median".

Mar 02, 2012 06:47 AM
 
davinhbrown

appriciate the upfront feedback with us, your customers.

Lots of other places would either leave it go with the mistakes, not inform us of particulars, or have the guts to answer the tough questions not only on this subject but all the articles.

Thanks.

Mar 01, 2012 18:28 PM
rating: 0
 
winder

Well whats up with the AL pitchers? Pecota has knocked off about 10 points of VORP from guys like CC,Lester and CJ Wilson.I would like for that to be explained to me.Is there something I`m missing? With these projections fluctuating,it makes me wonder at what point I can start trusting them.I'm not being cranky but I just don`t understand.

Mar 02, 2012 03:12 AM
rating: 0
 
BrewersTT

With respect, if your definition of trusting them is that they should consistently be less than 10 VORP off, you are maybe putting more faith in them than any sort of projection can really provide.

Mar 02, 2012 13:46 PM
rating: 0
 
BP staff member Dave Pease
BP staff
(2)

hi there. This is a result of the third point on the list that Rob mentioned. The pitcher WARP calculation had a bug in this year's version of PECOTA.

Mar 02, 2012 14:15 PM
 
Greg Ioannou

Ha! In the time it took me to draft a comment complaining that the math in the Visual Depth Chart was screwy, you fixed it. Way to go!

Mar 02, 2012 08:18 AM
rating: 0
 
derekdeg

Can someone tell me why PECOTA seems to dig Jose Altuve. Especially in NL 4x4 leagues. Whats with that?

Mar 02, 2012 20:24 PM
rating: 0
 
BP staff member Rob McQuown
BP staff

The projection for Altuve is .269/.300/.373, which hardly seems bullish to me, considering the damage he inflicted on the minors last year. For 4x4, he's fast, which always inflates a player's value.

I assume you're looking at PFM values, and this is where PFM can really help a fantasy owner get an edge. Second base is a very weak position (especially in the NL) this year. And while Altuve's low R and RBI totals hurt him, his batting average isn't terrible, his HR projection isn't quite as bad as you'd think based on his stature, his average is fairly neutral, and that speed really helps. All-in-all, PFM's scarcity-based valuations really bring to light how much a guy like that will help. And he's likely to cost only a fraction of his projected value in auctions.

Mar 03, 2012 09:09 AM
 
CalledStrike3

This (upgrade) is great ...better than adding Cliff Lee at the trading deadline.

Mar 12, 2012 05:47 AM
rating: 0
 
BBlackwell

This might be the wrong place for this comment, but my PFM is occasionally acting a little... well... funny. After I update after the occasional pick it groups ALL pitchers, relief and starter, into one group estimated at $0.

My positional needs are not filled, even at P, and even if they were I would have bench room where I would imagine Livan Hernandez would not be as good a choice as Max Scherzer, despite what my PFM is telling me.

Does anyone know what's up with this? It was fine for a while - for example, it was telling me Aramis Ramirez, Michael Bourn, and Chris Carpenter were the top 3 available players for my needs. Then, another team selected Dustin Ackley. That caused Carpenter to lose $100+ in value and drop to $0.

Is this a common issue?

Mar 13, 2012 20:24 PM
rating: 0
 
BP staff member Rob McQuown
BP staff

Thanks for using PFM!

The most common cause of something like this is running up against the budgetary constraints you configured in the league. If you modify the the budget settings and still see issues such as this, feel free to send your CID (it's part of the URL for the PFM report you're looking at, so you can just paste in the entire URL) to me via the "Contact US" page, we can look into what's going on with your particular league.

Mar 14, 2012 08:20 AM
 
Foster

Rob (and all) --

Maybe I'm just missing something simple but here something I've noticed over the past couple of fantasy seasons, and I don't know if you can speak to Baseball HQ's methods, but:

For the past few seasons, running my fantasy leagues through both dollar valuators, BP's CDM and your PFM, I've noticed that Baseball HQ $ values seem higher for a large number of players, compared to Baseball Prospectus'. It may just be perception; I haven't added up the dollar figures for the entire pool.

I understand that the projection systems differ, but shouldn't, on the whole, everything even out?

In particular, the BP values seem to greatly undervalue starting pitchers compared to HQ, with BP valuing saves and steals more.

Any insight? A difference in playing time estimates? A difference in just how much certain stats are valued in the standings?

Is it that BP squishes guys to the middle more than HQ?

Thanks,
Foster

Mar 18, 2012 20:17 PM
rating: 0
 
Foster

Looking more into the comparisons, it may be just that I'd been using the defaults: BP "forces position" while HQ does not. That option in HQ lowers their values more in line with BPs.

Again, I understand we're talking about two totally separate systems; I just couldn't figure out why BPs seems so nearly universally lower than HQs, given the same player pool and $ to spend.

Mar 20, 2012 02:15 AM
rating: 0
 
BP staff member Rob McQuown
BP staff

Not ignoring these well-thought-out observations, sorry for slow reply.

The short answer is that PFM constantly revisits the player pool for available values in every category, and so there's a very accurate assessment of exactly how much each player is worth, in terms of lost opportunity and benefit to the team. Offhand, I don't know why this would end up with a flatter curve. I do know that the "player pool" for some other projection systems are not made in such a way as to come out to league totals, given league limits on playing time, whereas the BP Depth Charts account for 100% PT and so the PFM "pool" is always going to be exactly MLB. We are discussing this internally, and may end up with a more in-depth reply at some point -- this would be a good topic for the Fantasy team to cover in a full-length article at some point, in fact.

Mar 20, 2012 07:13 AM
 
You must be a Premium subscriber to post a comment.
Not a subscriber? Sign up today!
<< Previous Article
Premium Article Prospectus Hit and Run... (02/29)
<< Previous Column
BP Unfiltered: Basebal... (02/29)
Next Column >>
BP Unfiltered: Top Min... (03/01)
Next Article >>
Premium Article Bates' Dugout Motel: V... (03/01)

RECENTLY AT BASEBALL PROSPECTUS
Fantasy Article Player Profile: David Robertson
Fantasy Article The -Only League Landscape: National League ...
Fantasy Article Tale of the Tape, Dynasty Edition: Nick Burd...
Fantasy Article Dynasty League Positional Rankings: Top 50 R...
Premium Article Rumor Roundup: Huston Street Might Have Reli...
Pitching Backward: In Search of the Winninge...
Rubbing Mud: A Solution Does Not Exist

MORE FROM MARCH 1, 2012
Future Shock: The Curious Case of Jairo Bera...
Premium Article On the Beat: Rethinking PED Testing
Prospects Will Break Your Heart: Spring Trai...
Premium Article Transaction Analysis: Notable NRI: AL East
Fantasy Article Resident Fantasy Genius: Fantasy Tier Rankin...
Fantasy Article Preseason Value Picks: Starting Pitchers for...
Premium Article Bates' Dugout Motel: Valentine Speaks!

MORE BY ROB MCQUOWN
2012-03-21 - BP Unfiltered: Free Trial - Scoresheet Draft...
2012-03-17 - BP Unfiltered: Spring Training Stats Don't C...
2012-03-09 - Fantasy Article Preseason Value Picks: Outfielders for 3/9/1...
2012-03-01 - BP Unfiltered: PECOTA and Depth Chart Update...
2012-02-24 - BP Unfiltered: Scoresheet Prospectus
2012-02-17 - Fantasy Article Preseason Value Picks: Outfielders for 2/17/...
More...

MORE BP UNFILTERED
2012-03-05 - BP Unfiltered: BP Names New Managing Editor
2012-03-02 - BP Unfiltered: Thank You Steven Goldman
2012-03-01 - BP Unfiltered: Top Minor League Prospects Co...
2012-03-01 - BP Unfiltered: PECOTA and Depth Chart Update...
2012-02-29 - BP Unfiltered: Baseball Prospectus 2012 Roun...
2012-02-27 - BP Unfiltered: The Artist is Moneymovie
2012-02-24 - BP Unfiltered: Fun with Baseball Reference
More...