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Wednesday, December 05, 2007

Baseball Prospectus and Sabermetrics

By , 01:25 AM

BP is one of the most notable and manistream sabermetric sites.  I happen to like it.  It has its weaknesses (don’t we all), but I think it is generally informative and valuable, if not occasionally groundbreaking.  I also think Pecota is one of the best and most innovative forecasting systems publically available.


Joe Sheehan is one of their most illustrative writers, I think.  I have talked to him on several occasions and he is a good guy.  He wrote this today about the recent Guillen trade.  To be fair, I am taking these quotes out of context:

Guillen’s performance has actually been consistent, and consistently good.

You hear comments about “consistency” all the time from the mainstream media, usually in reference to it being a good thing.  Acutally it is often used as a proxy for consistently “good” or just plain “good.” First, I don’t think that any player has any control over his consistency or that it is a repeatable skill, so why even mention that when talking about a player’s value in the future or analyzing a personnel move involving that player?  And even if it were worth mentioning, is there any extra value to an offensive player being consistent?  I doubt it.  Obviously it is more important for a player to be “good” whether consistent or not.  Sometimes (often actually), you would think that the mainstream media and baseball insiders would somehow prefer that a player be consistently mediocre or average than inconsistently good.  Obviously you would prefer the latter. Not to mention, “What defines being consistent or not?” I have no idea.  I assume there is a whole spectrum of performance distributions that could be interpreted as consistent OR inconsistent.

Now, has Guillen been consistently good as Sheehan says?  Well, his last 4 years’ offensive lwts (according to me) per 150 games were:

+10
+14
-14
+24

Is that good?  Sure.  Is that consistent?  I have no idea.  If you include 2006, which Joe wants to “throw out” (I’ll get to that in a minute), it does not look too consistent to me.  Even if you throw out 2006, 2007 is a big bump from 04 and 05.  Like I said, “consistency” is probably in the eye of the beholder.

And Joe did not say offensive consistency, although he probably meant that.  What about Guillen’s defense? 

04 -19
05 +10
06 -1
07 -19

Does not look too consistent to me.  But what do I know.

I really wish that any serious analyst would NOT use the word “consistent” (or “inconsistent") in their evaluation of a player (other than perhaps in describing something that occurred in the past without necessarily implying anything about the future). If I ever do, you have my permission to shoot me (virtually of course).

Toss out 2006, which was a season marred by injuries

Let’s just toss out 2006!  He may have been injured, but to just decide to “toss out” an injury-plagued year?  First of all, what a player does is part of his performance history, injured or not!  Players get injured.  Part of a projection includes the chance that he gets and plays injured in the future.  If we only use and project “perfect health” data, well.... And who is to say what data gets tossed and what data doesn’t?  That’s easy, right.  If we want a rosy projection, we’ll just toss out all the bad data when we “think” that a player was playing injured.  If we want a poor projection, we’ll just keep that data.  I don’t have much of a problem “tweaking” data and projections based on injury histories and the like, but if you do that, you are treading in dangerous waters.  And to just “throw out” an entire year (albeit only 264 PA so it is not THAT big a deal), well, I already said enough about that.

and since his 2003 breakout Guillen has played in 148, 148, and 153 games, with EqAs of .282, .283, and .285.

Two things here.  One, if I ever use the word “breakout season” in an analysis, you have permission to kick me.  Technically, he did have a season in 03 which was well above his career norms up to that point, but Tango, I and others have shown on numerous occasions that breakout or banner years have no more or less predictive value than any other year.  When you say “breakout year” you are implying that that year is a new level of true talent and that you can more or less throw out all prior years.  Nothing could be further from the truth (O.K., some things could - just listen to George Bush, Dick Cheney, et al.).  In 03, Guillen was +28 in lwts.  In 02, he was -3 and in 01, he was -9.  Without 01 and 02, we might be tempted to think that the +28 was his new level of true talent (of course, regression toward the mean would tell us anyway that it was not).  However, a +28 after a -9 and -3 is A LOT different from a +28 after a +20 and a +16, for example.  Sure, players sometimes change their true talents a lot (I guess).  But ALL players have the potential to fluctuate randomly from year to year like a mad dog (no reference to Maddux) or a banshee.  It is no accident (well, maybe it was) that in 04 Guillen “regressed” to +10 and in 05, +15.  We could have anticipated that from his 01 and 02 numbers, prior to his “breakout” (choke, cough!) season.

Second thing:  Sheehan says that his EQA’s in 04, 05, and 07 were .282, .283, and .285.  (Oddly, he says, “Since his 03 brealout season” - apparently he is throwing out 06 again, although he does not specifically say that in those sentences.) Anyway, since EQA is supposed to be a proxy for lwts, his lwts rate should all be around the same in those 3 years, right?  Wrong!  Here are MGL’s (the most accurate account of a player’s context-neutral offensive performance that I know of - the “gold standard"):

04 +10
05 +15
07 +23

O.K., those are fairly close, but as you can see, EQA, like OPS and the other “lwts proxies,” are crap when you are trying to rigorously evaluate a player.  Well, maybe our park adjustments are different but equal in “value” so I’ll give him (and EQA) a pass on that one.

He is generally considered a good right fielder with a strong arm; Clay’s system gives him -16 FRAA this year, which may or may not have something to do with Ichiro Suzuki’s play in center field, but regardless, that data point is aberrant.

First, I doubt that any bad defensive rating has anything to do with “Ichiro’s play in CF” and anyway, FRAA is a goofy metric and does not use PBP data I don’t think.  A metric for the OF without PBP data is practically worthless I would think.  That being said, his UZR in FRAA this year was -19!  About the same as Clay’s (blind squirrell - actually a good non-PBP metric for the OF will obviously come close to a PBP one).

Good arm?  Arm lwts is one of the easiest things to measure.  You look at base advances and assists per opportunity and compare that to the average player at that position with park adjustments and you can even do adjustments for where the ball was actually hit in the OF.  And BTW, we commonly forget, but a player’s “arm” rating is a combination of the strength and accuracy of his arm (as well as his reputation) AND how fast he gets to the ball!  Anyway, while in LF, Guillen had a GREAT arm rating, and that was last in 04 when he was young.  Since then, he has been in right field (where the average arm is MUCH better) and he has NEVER had a positive arm rating.  So yeah, he probably has a strong arm (although probably not as strong as it used to be), but it probably is now about average for a RFer.

In any case, Guillen, according to UZR, is NOT even an average defensive outfielder any more.  In Dewan’s system, I don’t see him on the 05-07 trailer or leader lists.  I think that Tango’s fans rate him as average.  So who “generally considers him a good RFer?”

Finally, if I ever use the word “aberration” to refer to a particular season…

Seriously, some analysts use that word as if to imply that we should throw out or give less weight to a period of time in which a player’s performance is far from his established level, both before and after.  Sheehan certainly does imply this.  First of all, according to UZR, it is NOT an aberration (04 was the same).  More importantly, again, as Tango, I, and others have shown, “aberration shmaberration.” All levels of performance gets treated equally in terms of estimating a player’s true talent or projection.  Doesn’t matter whether it is close to a player’s established level or not.  A lot of people don’t get this.  Apparently Joe is one of them.

The price, $12 million a season, is almost reasonable in this market; just to pull a name out of thin air, Guillen has outhit Gary Matthews Jr. in three of the last four seasons, and is almost certainly a better player than the man with four years and $40 million left on his deal.

Almost certainly a better player than Matthews??  Wow!  I have Guillen projected next year as 1 to 1.5 WAR.  Matthews as 2.5 WAR.  He is right but has those players completely backwards.  The positions alone, even if they were defensively average at their respective positions are like 1 to 1.5 wins apart!  How can Sheehan get this so wrong?  And if I ever say something like, “So and so has outhit so and so in 3 out of the last 4 seasons,” please, well, you get the idea.

Player A
+3
0
-21
-4

Player B

+1
-2
+9
-5

Well, you get the idea again (Player A outhit player B in 3 of the 4 seasons)…

So Guillen is a better player than I thought he was, a better player than I give him credit for. Does that make this a good signing for the Royals? I’m not sure what they gain by adding a low-OBP, high-SLG corner outfielder.

Does it matter if a player is a low-OBP, high- SLG, or high-OBP, low-SLG (assuming you are not using OPS ro evaluate them), high-forehead, low-hanging...?  You get the picture again.

Just adding Guillen to the Royals makes them perhaps a win better

I have no idea whether that is true or not.  He lost me at “consistent.”

#1    vj      (see all posts) 2007/12/05 (Wed) @ 08:05

Minor detail: Jose Guillen was not traded but signed a free-agent deal. I was confused for a while which Guillen you’re refering to.


#2    jonm      (see all posts) 2007/12/05 (Wed) @ 08:29

Great analysis, MGL—it’s a real joy to read sober-minded analysis.  I think that the problem lies in the fact that BP is a middlebrow site, that is, it’s somewhere between sabermetrics and old-time hack sportswriting.


#3    MGL      (see all posts) 2007/12/05 (Wed) @ 11:32

#1, yes of course.  #2, thanks.


#4    tangotiger      (see all posts) 2007/12/05 (Wed) @ 11:38

Funny, as Joe concludes:

League-average players have value, and Guillen is that

And that’s exactly what I called him!  A league-average player.  League-average players however make 9MM this year, and, if you are league-average at age 32, you are likely out of baseball at age 35.


#5    MGL      (see all posts) 2007/12/05 (Wed) @ 14:27

Yeah, I wouldn’t have any problem calling him league average, although I have him as almost a win worse than that based on his poor UZR projection.  I HAVE heard that he can’t run anymore, which would not be surprising for an early thirties oft-injured player.  If he “can’t run anymore” it is unlikely he is even a league average defender in the OF, as my “speed versus UZR” study showed.

I don’t think that BP is quite at the (low) level of being “in between a sabermetric site and a hack mainstream site.” I think that they have too many writers (not all of them being even close to experts in sabermetrics), and they have a different agenda than just trying to “tell the truth” - which is to make money of course.  Plus, they are only a group of fallible human beings.  We make lots of mistakes here on this blog, but because of the format and our non-monetary agenda, we have a chance to vet many of them.


#6    Tangotiger      (see all posts) 2007/12/05 (Wed) @ 15:17

Guillen has a specific combination of tools:
http://www.tangotiger.net/scouting/sim2007_5753.html

All of his top comps are RF, 3B, and catchers (that is, heavy arms, heavy legs). 

Among the OF, his top comps according to Fans (UZR/150, from 03-mid07 are in parens): Vlad (-4), Jayson Werth (+5), Abreu (0), Hawpe (-4), Dye (+1), Nady (-2).  That doesn’t include their UZR arms, which likely would add 1 or 2 runs each.  Overall, Guillen’s top comps are basically average RF according to UZR.  The average Fan rating has them at just a sliver above zero.

If I had to guess on Guillen’s UZR for 2008, it will be the regressed about 80% toward the average of these 6 RF, be it UZR or Fans’ ratings.  I don’t think you can call him at anything worse than a -5 run RF.

In any case, you would need to cap his fielding in RF at -15 runs.  Anything worse (-15 runs in RF, plus the -5 positional adjustment) means that he’s a DH.  SS can go as low as being -25 runs in UZR, and 1B can be as low as -10 runs in UZR.  Anything worse than that means that they should only be a DH (or see if they can leverage their fielding at some other position).


#7    David Cameron      (see all posts) 2007/12/05 (Wed) @ 15:20

Guillen suffered through some ankle problems in the first month of the season, serious enough to the point that he was being removed for Jason Ellison in late innings on a nightly basis.  For about the first 30-40 games of the year, he ran like a wounded solider. 

The ankles healed as the season went on, and his defense improved.  His range isn’t great, but I’m with Tango - he’s a -5 type fielder, not a -15 type fielder.


#8          (see all posts) 2007/12/05 (Wed) @ 15:29

I think you’re misinterpreting the term “breakout year”.  I look at it to mean, “you should value the breakout year more than you normally would, and other years less than you normally would, in projecting forward”.

And truly, if someone had the skill to recognize Guillen’s 2003 as a breakout year, I’d bet their projection for him for 2004 would have been more accurate than something like Marcel.  In other words, if Marcel uses the 3, 2, 1 weighting, a breakout year might necessitate a 5, 2, 1 weighting.


#9    tangotiger      (see all posts) 2007/12/05 (Wed) @ 15:32

Injuries (or fear of injuries) are by far the biggest determinant in fielding impact (UZR runs or whatnot).

One of the biggest UZR stars through 2004 was Mark Kotsay.  In 2005, with a bad back, he started his downward flight in UZR.  Rowand was a UZR star through 2005.  Then we know what happened in 2006.  Fielders have nothing to fall back on when they get hurt. 

Hitters on the other hand can compensate to some extent (Andres Galaragga is probably the best example).

When it comes to fielding, I’d need to know if he was injured, and if it’s a potentially recurring injury.


#10    tangotiger      (see all posts) 2007/12/05 (Wed) @ 15:51

Not that it matters in this discussion, but Marcel uses 5/4/3.

As for “breakout year”, it is far more commonly accepted that it’s not simply a reweighting from 3/2/1 (50% for most recent season) to 5/2/1 (63% for most recent season).  That’s barely a change.

No, it’s more like if you consider Beltre’s 2004 season, that if this was his breakout year, you’d weight that season far far more than his prior seasons.  You’d do at least 80% of the weight, if not 90%, with a tiny bit of allowance that 2004 was not a breakout year.


#11          (see all posts) 2007/12/05 (Wed) @ 17:21

http://www.baseball-reference.com/p/putzjj01.shtml

Probably follows your 80-90% definition of breakout year.  Of course, this is a sample size of 1, but if I were a betting man I’d have bet a fairly sizable chunk of money that Putz would have had a 2007 that was very similar to his 2006, and not 2005-earlier.  Why?  Because he learned to throw the splitter before 2006.

I don’t believe research that says breakout years have no predictive impact.  The problem is, we aren’t looking at enough data.  Put a column in the model for “learned a new pitch”, and see what happens.  Same with “lost 8 mph on his fastball”, “got laser eye surgery”, “started hanging out with Greg Anderson”, “hat size grew by half an inch”, and “gained 30 lbs”.

I guess your point is that, at the time, we’d consider Beltre’s 2004 and Putz 2006 as two instances of the same “breakout” thing.  And I can see why you’d conclude from a bunch of those types of seasons that there’s no true new level of talent established.  But I guess the baseball romantic in me wants to believe that there IS a way to identify true breakout seasons - true seasons that establish a new talent level - and I think the data is there to do so if we look for it.


#12    tangotiger      (see all posts) 2007/12/05 (Wed) @ 18:07

Certainly there is a way to identify it.  You CANNOT identify it by looking at the seasonal aggregate data, which is what virtually everyone does.


#13    MGL      (see all posts) 2007/12/05 (Wed) @ 19:08

Mike, pitchers are much more likely to have seasons where their true talent changes considerably.  That is the main reason why we weight recent seasons more aggresively with pitchers.  Certainly, if you KNOW that something changes, like a new pitch or an injury, or recent great health (maybe), then you can do your own “seat of the pants” weghting, or tweak the projection, or what have you.

With batters it is MUCH harder to identify something fundamental that has changed, BEFORE (or concurrent with) the fact.  After the fact, everyone has a “reason” for the breakout, just like all successful teams had great chemistry (as Tango says, let’s identify the good or bad chemistry before the season starts, just one time), etc.  Players are always coming into camp in the best shape of their lives, injury-free (finally), yada, yada, yada.

We are pretty much just talking about looking at the numbers Mike.  No one (with any sense) is going to argue that if you KNOW (or even suspect) something has changed fundamentally with a player, that you want to use the same old Marcel to project his performance.  But without knowing anything but the numbers, the research has shown that ANYTHING but the usual Marcel weightings do NOT work as well even after a banner year, either poor or good.  There are some qualifications to that.  For certain component stats, at certain ages, and certain types of banner years, there are better weightings than Marcel, but they are subtle.

But my point still stands (and much of my initial post was a little hyperbolic and sarcastic with a feeble attempt at humor, so don’t take it too seriously or literally) that the way most people look at “breakout” seasons (a heavy weighting to that year) is simply not correct.  And I don’t like to even use that term.  A season is a season.  And sure, after a breakout season, a player’s projection, by definition goes up a lot - just not as much as most people think.  As well as the fact that prior years are still very important.  A lot of people will think that a player, say at 27 or 28, when players are supposed to have breakout seasons, who posts a +20 at age 28 after a +3 and +5 is about the same player going forward as a player who posted that same +20 after a -12 and a -3 or even a -12 and a +7.  They are not.  All years count.


#14    studes      (see all posts) 2007/12/06 (Thu) @ 09:53

So much in that post, MGL!  One comment that comes to mind for me: I disagree with you regarding consistency.  Consistency is not just a statistical phenomenon.  Some players have a skillset that tends to yield more consistent results over time.  A strikeout pitcher, say, than a pitcher who relies on his fielders.  Or power vs. contact hitters.

Secondly, I believe some players are inherently streakier than other players and that can have an impact on seasonal results.  Tony Gwynn was a remarkably consistent offensive player.  Cal Ripken tended to have a few great among many average seasons (offensively) (caveat—I named those two players off the top of my head due to their recent Hall of Fame induction.  May not be a valid comparison).  I think consistency is a player attribute, often related to injuries, true, but sometimes related to something about the player himself.  We can argue about whether it’s good or bad, or how to measure it, but I do think it exists.


#15    DanAgonistes      (see all posts) 2007/12/06 (Thu) @ 14:25

Just a comment on Guillen’s arm. For 2005-2007 in right field I have him at +2.1 runs total in 335 adjusted games with exactly average performances in 2005 and 2006 and a better 2007. This metric looks at all advancement opportunities and uses run expectancy. His performance in 2007 ranks him eighth among regular right fielders with the likes of Markakis and Abreu.


#16    Tangotiger      (see all posts) 2007/12/06 (Thu) @ 14:48

Good stuff.  Here’s what the Fans say for RF (any RF not listed means he was +/- 1 run).  These are runs per 162 G.

Arm Player
5 Young, Delmon
5 Victorino, Shane
5 Francoeur, Jeff
4 Cuddyer, Michael
4 Rios, Alex
4 Hawpe, Brad
4 Markakis, Nick
3 Kearns, Austin
2 Guerrero, Vladimir
2 Guillen, Jose
...
(2) Encarnacion, Juan
(2) Lewis, Fred
(3) Hermida, Jeremy
(3) Wilson, Preston
(3) Murton, Matt
(3) Pena, Wily Mo
(3) Nixon, Trot
(3) Green, Shawn
(4) Floyd, Cliff
(5) Cust, Jack
(5) Gomes, Jonny
(5) Sosa, Sammy

I have to believe that Arms is the easiest thing for Fans to judge.  John Walsh did a series a year or two ago that also compared to the Fans.

If Dan or MGL want to compare their 3-yr arms runs to the above, it would be most interesting.

Related links from John Walsh:
http://www.hardballtimes.com/main/article/cannons-and-popguns-rating-outfield-arms/

http://www.hardballtimes.com/main/article/more-guns-in-the-outfield-center-and-left-field/


#17    MGL      (see all posts) 2007/12/06 (Thu) @ 14:52

Dan, I have him at zero in 05 and 07 and -2 in 06, using exactly (more or less) the same methodology.  Let’s split the difference!

Studes, I believe that the Earth is flat and although I am a pretty smart guy overall, that does not make it so.

If you have some evidence that consistency among players is a skill (other than the K pitchers, etc., example you give, which is correct, although I am not sure how much difference that makes - but we can surely check), give me a ring.  It is easily checked of course.  And why would you give examples of players who were more or less consistent throughout their careers as if that were evidence of your belief?  We KNOW that ABSENT a “consistency skill” there will be plenty of players who, by chance, were anomolously consistent or inconsistent for their entire careers, right?

O.K., it is the holliday season.  I’ll give you a pass on using examples for “illustrative purposes.” Let’s just not mistake that for evidence! wink

If I have a chance later on, I’ll actually look at the data.  I have wondered that for a while - whether “consistency”, over and above a player’s “profile” (K and BB rate, which are obviouslt more “stable"), is indedd a skill, and if yes, to what extent.  Of course, most of things (consistency, clutch, etc.) are probably a skill to one degree or another.  The real question is whether it is a “significant” skill, however you want to define “significant” of course.  For example, Andy found that clutch hitting is probably a skill, but so small that is makes no practical difference, except perhaps as a tie-breaker or as a little “extra” value (positive or negative) over the course of a long career.


#18          (see all posts) 2007/12/06 (Thu) @ 19:33

Yes, you can probably watch a player throw once or twice and accurately rate his arm (like speed, just watch a player run hard once), but…

Arm value is different.  It includes accuracy, which is NOT as easy for fans to judge, although if they see a player enough, I think they can.  It also includes speed to the ball and setup.  Fans can probably judge setup (although they are more interested in arm strength I think), and I think they largely ignore speed to the ball.  Maybe you should include that if you don’t already.

Finally, the reputation of the OF’er (what the runners and coach think) is part of his arm value.  The fans are probably not including that at all.  An OF whose rep is less than that of his arm is going to have more value and vice versa.

The nice thing about the fan ratings though is they can “adjust” for where the ball was hit, whether a runner made a mistake, whether no arm would have gotten a runner, etc.  In fact, the fans may be better than the numbers for a year or perhaps even two.  I am not sure of the ratio I would use to combine them, but for arm, I might use 75/25 or 60/40 fans for one year and 50/50 for two.

Of course it depends on how the fan data is collected.  There are a lot of potential biases among the fans as we have seen.  It would be a lot better if the fans would “rate” a player who they have never heard of and have to put how how many times they have seen him, etc.  I am sure we have some fans who see a player a few times and then pretty much just put down what they “have heard” or their observations are influenced by what they have heard (or read) or what they have seen in years past, etc.

BTW, anyone know why I cannot select certain text with my cursor and/or keys using IE 6 on this blog?  I can only select text from my cursor to the top of the page.

Here are my 07 and then 04-07 numbers:

Arm Player
5 Young, Delmon +13! Of course he was -17 in UZR.
5 Victorino, Shane 15/9!
5 Francoeur, Jeff 18/9
4 Cuddyer, Michael
4 Rios, Alex 19/11
4 Hawpe, Brad -5/3 (+13 in 06)
4 Markakis, Nick -8/-3
3 Kearns, Austin -6/-1
2 Guerrero, Vladimir -3/-1
2 Guillen, Jose 0/0
...
(2) Encarnacion, Juan -3/-2
(2) Lewis, Fred -1/-1 (Fred Lewis?)
(3) Hermida, Jeremy 1/0
(3) Wilson, Preston -2/-5 (He is bad as a CF!)
(3) Murton, Matt 2/2
(3) Pena, Wily Mo 0/1
(3) Nixon, Trot -5/-4
(3) Green, Shawn -5/-5 (along with -4/-8 in UZR.  He is a replacement player.)
(4) Floyd, Cliff -4/-3
(5) Cust, Jack -4/-4
(5) Gomes, Jonny 2/0 (he is mostly a DH)
(5) Sosa, Sammy -2/-3

Hawpe, Markakis, Kearns, and Guerrero seem to be way off.  They seemed to have gotten most of the bad ones correct.

Tango, do they rate players independent of position?  And then do you adjust for position?  Obviously an average arm in RF would be tremendous in LF.  Etc.


#19    tangotiger      (see all posts) 2007/12/06 (Thu) @ 21:07

Yes, independent of position.

That’s the cool thing doing it that way.  I know exactly how much the translation should be in arm, between LF and RF.  I’ll tell you that tomorrow when I get in.

Looks like all the very good and very bad, we have great agreement on. 

For Vlad, it’s possible that my weighting of “release/footwork”, “accuracy”, and “strength” is not correct.  I gave them each equal weight.

Hawpe seems to be ok.  Just this year, the UZR seemed off.  Markakis is probably the biggest difference.


#20    Los Angeles Waterloo of Black Hawk      (see all posts) 2007/12/06 (Thu) @ 21:30

Finally, the reputation of the OF’er (what the runners and coach think) is part of his arm value.  The fans are probably not including that at all.

Should we be?  I thought the project was meant to assess actual physical tools.


#21    Pizza Cutter      (see all posts) 2007/12/07 (Fri) @ 13:26

Re: consistency/aberrations.  What you are describing is an outlier datapoint.  (e.g., Beltre 2004).  It can mess a lot of things up when you put too much faith into an outlier.

That said, we do have a few metrics to give us some insight concerning whether a breakout/breakdown season is the product of a new skill or luck (i.e., an outlier).  For example, a pitcher goes from being a 2.50 ERA guy to a 4.50 ERA in the same season that his BABIP goes way up.  We know BABIP is largely a function of chance.  I suppose a few investigations could be undertaken to see what factors might distinguish players who have an abberation season vs. developing a new skill.


#22    MGL      (see all posts) 2007/12/07 (Fri) @ 13:31

Sorry, I meant “reputation” in terms of what the baserunners do.  If an OFer has a reputation for a powerful arm, justified or not, runners will not attempt the extra base and vice versa.  So an OFers arm value is his arm PLUS what the baseruners do.  The fans are only rating the first part of the equation, of course.


#23    Tangotiger      (see all posts) 2007/12/07 (Fri) @ 14:17

Here’s a Banner Years study of mine from a few years ago:
http://www.tangotiger.net/archives/artBanner.shtml

It looked at overall performance levels.  It’s possible that focusing on component-based will give you different answers.


#24    studes      (see all posts) 2007/12/07 (Fri) @ 20:15

Studes, I believe that the Earth is flat and although I am a pretty smart guy overall, that does not make it so.

Obviously, you’ve been reading Thomas Friedman lately!

Seriously, I don’t have the skill or mathematical chops to figure out whether consistency is an actual skill or not, or whether it is “significant.”

But count me among those who believe that people won’t come to a firm “no” conclusion based on any statistical analysis.  There will always be room for our opinions, thank goodness.


#25    MGL      (see all posts) 2007/12/08 (Sat) @ 00:14

There is NEVER a firm answer when analyzing sample data. I have been preaching that for years.  I have also been preaching that there is ALWAYS a significant chance of the existence of a small effect when we cannot find any effect, also given less than an enormous data set (less than an infinite set actually).  All we can do is say that we think there is an X percent chance (or we are Z confident) that there is (or is not) a Y effect.  Which is usually good enough for government (or baseball) work.

Actually, in reality we are usually looking for evidence that a significant (however you want to define that of course) effect exists.  If we are lucky enough to have enough data, we can usually answer the question of whether, “There exists evidence that a significant effect exists or doesn’t.” Again, in practice, at least in baseball research, occasionally the results are equivocable.  Then, if we can increase the sample size being studied, or change the methodology in some other way, we can often come up with a “less equivocable” (I guess technically ALL answers are equivocable when dealing with sample data, as I already said) answer.  Sometimes, we are simply stuck with an equivocable answer, or no answer at all, if you will.

As for opinions about factual things without any factual data to back them up…

We get enough of that from politicians. wink


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