New Fielding Stat

[Basketeer]

These stats are completely stupid. If a player can consistently catch the ball and make smart plays in the field, I couldn't care less what his USZ, PoS, GrrI, or JTi are.

[Old#5fan]

These stats are completely stupid. If a player can consistently catch the ball and make smart plays in the field, I couldn't care less what his USZ, PoS, GrrI, or JTi are.

Although I tend to very much agree with you, be alert to the fact there are many others here who will not like your take on this subject.

[BaltimoreTerp]

These stats are completely stupid. If a player can consistently catch the ball and make smart plays in the field, I couldn't care less what his USZ, PoS, GrrI, or JTi are.

Well, then I'm glad you get to watch every single play of every single player on every single team for every single game in every single season, AND can remember all of that information.

Some of us aren't blessed with that amount of intelligence or complete lack of a life and therefore need some way to figure it out on our own. How about we develop our stats, and you keep doing things your way?

[Pedro Cerrano]

These stats are completely stupid. If a player can consistently catch the ball and make smart plays in the field, I couldn't care less what his USZ, PoS, GrrI, or JTi are.

I'm glad you've decided to boil your assessment of fielding ability down to such concrete, tangible terms like "catch the ball" and make "smart plays.":rolleyes:

[Pedro Cerrano]

BTW, I think hitters are good hitters if they can hit the ball a lot and can hit it far a lot too.

[PaulBako]

So many stats! So many stat nerds!

[Basketeer]

Well, then I'm glad you get to watch every single play of every single player on every single team for every single game in every single season, AND can remember all of that information.

Some of us aren't blessed with that amount of intelligence or complete lack of a life and therefore need some way to figure it out on our own. How about we develop our stats, and you keep doing things your way?

Why the personal attack, champ?

How about we start judging players on their ability to play instead of making up worthless statistics to justify having them?

You show me how fielding percentage on days with 76% sunlight in July divided by shoe size is at all relevant, I'll admit I'm wrong. That's exactly what these stats are, completely ridiculous attempts to justify mediocrity.

[BaltimoreTerp]

Why the personal attack, champ?

How about we start judging players on their ability to play instead of making up worthless statistics to justify having them?

You show me how fielding percentage on days with 76% sunlight in July divided by shoe size is at all relevant, I'll admit I'm wrong. That's exactly what these stats are, completely ridiculous attempts to justify mediocrity.

Officially hopeless.

[Basketeer]

BTW, I think hitters are good hitters if they can hit the ball a lot and can hit it far a lot too.

I put stock into AVG, OBP, SLG, OPS and not a whole lot else.

[Basketeer]

Officially hopeless.

I'm sorry to question you, owe Grand Poobah of Baseball Knowledge.

[Basketeer]

Well, then I'm glad you get to watch every single play of every single player on every single team for every single game in every single season, AND can remember all of that information.

Some of us aren't blessed with that amount of intelligence or complete lack of a life and therefore need some way to figure it out on our own. How about we develop our stats, and you keep doing things your way?

I like how the guy with 16K posts on a message board says I have no life.

[BaltimoreTerp]

I'm sorry to question you, owe Grand Poobah of Baseball Knowledge.

Hey, I'm not the one trashing people who are trying to find ways to measure what they see on the field and use it to discover knowledge about the sport. That would be you.

Defensive stats aren't perfect. Most really aren't that great. But you can't just make a wholesale rejection of everything.

Especially when your reasoning involves an impossibility. I brought it up in sarcasm, but that is essentially what you are saying; you watch and remember EVERYTHING.

And then when challenged, you make the statement "fielding percentage on days with 76% sunlight in July divided by shoe size" which is about as moronic a statement as one can on the subject. It makes you sound unintelligent and someone who doesn't want to learn new things.

I really doubt that is either what you are or what you want to come across as, so I suggest we just let this drop. Your attitude shows entrenchment towards your position, so I don't think there is any point taking this further.

[Baltimoron]

I still like the plus minus system because it actually looks at the all the attempted plays that the fielder should have made vs. the ones they actually made.

That's what UZR is. The Fielding Bible's +/- is patterned off UZR, which came first. As SG said, UZR has been around a while.

It was created by "mgl", one of the authors of "The Book." And UZR as published on Fangraphs uses the same data as +/- (Baseball Information Systems - BIS data), but contains more adjustments like for park, pitcher handedness, etc than +/-.

Unlike other versions of UZR, the ones that appear on FanGraphs use Baseball Info Solutions location data instead of STATS location data.

link.

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Ultimate Zone Rating (UZR)

UZR is often heralded as the gold standard of defensive stats. I agree that it's very good, but as we'll see in the comparisons article, I'm not convinced it's the only thing worth paying attention to. It is the creation of Mitchel Litchman (aka MGL), and his methodologies are described in detail in these two posts at BBTF. In its most basic form, it's a pretty simple procedure, and it serves as a nice model to understand the other zone-based stats, so I'd like to walk through it.

Essentially, the ball field is broken up into different zones, which are the hit location zones defined by Project Scoresheet/Retrosheet (see figure to right). If one pays $10,000 to get hit location data from STATS Inc (which no individual fan except MGL has been willing to do)(note Fangraphs publishes UZR calculated with BIS data), one can calculate how many balls were hit into each of these zones. And, for each position within each zone, one can determine the percentage of those balls that were typically converted into outs.

From the raw data, one can also measure how many balls were hit into each zone when a particular player was on the field at a given position, and how many of those balls were turned into outs by that player. And using that information, you can get the percentage of batted balls that the player converted into outs within that zone.

Let's say that the average shortstop converts 21% of balls hit into zone "56" into outs ("56" is the zone corresponding to the "hole" between third base and shortstop). And, let's say that Larry Barkin played the entire season as the Reds' starting shortstop, and he converted 25% of balls hit into zone 56 into outs. Based on that information, I think most folks would be comfortable saying that he was better than average, at least on balls hit into that zone.

But how much better? Well, 25%-21%=4%. But how much better is 4%? Well, let's say that there were 100 balls hit into zone 56 while Barkin was playing. If the average shortstop turns 21% of zone 56 balls into outs, that means the average shortstop would be expected to make 21 plays in Barkin's situation. And yet Barkin made 25 plays. Therefore, I'd say that Barkin performed 4 plays above average in zone 56. Now, let's say that we did the same procedure in all other zones on the ball field, and Barkin's rate matched the actual rate exactly in those other zones. The summed difference between Barkin's rates of making outs and the average shortstop's rates of making outs would then be +4 plays, which would be entirely due to his excellence in zone 56.

Ok so far? What if we want to know the approximate run value of this better-than-average performance? Well, using linear weights, we can determine the average runs value of hits that go through zone 56 around the league. For the purposes of this illustration, let's say that every ball hit through zone 56 in baseball turned into a single (in reality, some turn into doubles or triples, but this isn't too far off). The marginal linear weights value of a single is ~0.460 runs, so Barkin's performance prevented ~0.46 x 4 = 1.84 runs from occurring via these singles. Furthermore, he also generated four additional outs, each of which is worth ~-0.265 marginal runs, so he prevented 0.265 x 4 = 1.06 runs by generating these four outs. This puts Barkin's total fielding value at shortstop, given that he was +4 plays above average, as 1.84+1.06 = +2.90 runs saved above average (~0.725 runs saved per play above average). This is the estimated improvement in defensive performance over what you would probably have gotten from a completely average shortstop had he played instead of Barkin.

This, in a nutshell, is what UZR does. You'll note that the rates from which we're calculating the +-plays above follow the same generalized formula that we presented at the top of the article: outs/opportunities. It's just that instead of having to assume that opportunities are only those balls that a player got to, or that the average number of opportunities per game was constant, the zone system allows us to get a much better estimate of the number of opportunities a player actually had.

In reality, UZR is a bit more complicated than I indicated here, using different rates to account for batter handedness (attempts to adjust for positioning), how hard a ball was hit (to account for difficulty), as well as adjustments for defensive park factors and a few other things (you can refer to MGL's two articles for more info). Nevertheless, this should give you a basic understanding of how it all works. And that should help you understand the remaining stats as well, as they're all pretty similar.

link.

BIS's Plus/Minus System - the Fielding Bible (+/-)

The RZR numbers are based on the same raw dataset that Dewan's company (BIS) has used to create their own advanced fielding metric, which they refer to as the "plus/minus" system. In the outfield, it essentially operates in the same way that UZR does, where a player's performance is compared within each zone on the field to the average performance of others at his position, rather than just in zones that are assigned to a particular position. On the infield, rather than using zones, it instead uses vector slices to divide up the field...though in practice, it's pretty much the same thing.

I like the plus/minus system. Unfortunately, it's not freely available. (You can get +/- leaderboards here and all +/- info with a subscription at billjames online)

link.

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Here is a new thread at "the Book Blog" in which you'll likely have mgl and others addressing the reliability of UZR and other defensive measures.

[Greg Pappas]

Stupid this, get a life that, your info is worthless, you get outta your mom's basement much?, my racist comments were to be taken as a joke, I can't type properly because I'm texting from my phone, I was drunk when I wrote that so gimme a break, my opinion is great yet your's has no redeeming value at all...

Why do we, as human beings, feel the need to say hurtful things, so very often? Family, friends, co-workers... it happens everywhere. But among those on the internet, behind the alias' we hide behind, some feel the freedom to post online in a way that they might not in person. Why? Because online society has -in many ways- developed a culture of incivility that allows one to take out life's hardships on those who have little defense against it. The aggravations of the day spew forth, venom for those that one has disagreement with.

Yet, here at the OH we are built to rise above it all. Here in the place that Tony began with the idea that true Orioles fans would have a place to come, a place that would earn the reputation as a haven for those tired of the bickering, rudeness, and juvenile ramblings that permeate the web. He succeeded, with help from a lot of great people. But lately there has been a growing faction within our community that feel that their posting is a right, rather than the truth of the matter... that it is a privilege.

Please try harder folks... keep our community as it was intended, and thanks for hearing me out.

[Baltimoron]

UZR/150 just doesn't pass the smell test. Look at RF

Winn 18.9

Fukodoma 13.4

Giles 10.4

Markakis 3.4

How is there such a deep drop from the top 3 and the 4th. And why are the top 3 all from the NL?

You are looking at qualified leaders, or only the guys who played like 950 innings in RF. Click on "all players" to the right and top.