Meaning of LIMA grades?

[kehardwick]

I understand the broad idea--but I don't understand the process by which LIMA grades are assessed in the first place.

Here's an example: Travis Hafner, rated a B+ at $1, and a B+ at $10, and a B at $20.

How did BBHQ come up with those numbers? Given his BPIs, I would think that Hafner would be a superb LIMA player, were I lucky enough to have him at $1.

I find that the utility of the various metrics and assessment tools offered by BBHQ is vastly enhanced when I understand the thinking behind them. That let's me integrate these tools into *MY* ways of thinking, and use them for my purposes. I can't find a detailed description of this particular tool, however, and thus I am not sure how best to use it. What is the process by which these grades were determined?

Here's the explanation from Baseball Forecaster, relating to hitters:

"Lima grade: Rating that evaluates how well a batter would fit into a team using the LIMA Plan. Best grades go to batters who have excellent base skills (BPV), are expected to see a good amount of plying time, and are in the $10 -$30 Rotisserie value range...."

At the start of the year, HQ projected Hafner at $14, a BPV of 49, and 543 AB. His standing on the first two criteria make him a good but less that ideal LIMA candidate, he is on the low side of the Roto $ range and only average in BPV for his position. But he had the potential to improve.

I have no problem with the B+ LIMA grade for him at $10 under this approach. While it wouldn't be a major problem to call him an A- at $1, the logic behind the B+ here is that a LIMA team needs to load on offense, and putting a $14 player at a key offensive position such as 1B may not be optimal spending. While Hafner has done extremely well this year, if he had gone in the other direction (say -$10 from his projected $14 value), filling a 1B slot with a $4 hitter could have been a problem in LIMA.

Having said that, these are not hard and fast rules, and there is a certain margin for error. I would have been happy with getting Hafner at $1.

[kehardwick]

Followup

Thanks much for the quick response. In retrospect, I should not have mentioned Hafner at all, since I mentioned him only for illustrative purposes. What I really want to know is *HOW* you go about making the assessment.

Is it mostly a subjective judgement (a comparison versus particular criteria or rubric, much the way I might go about grading a student's paper--not arbitrary since there are real standards in place, but definitely subjective), or is there a more quantitative algorithm in place? If it is subjective, who makes the grade decision? The BBHQ analyst who wrote up the player?

Many thanks.

[kehardwick]

You never know when you post to a BB--its very easy for a post to convey unintended subtexts. At any rate, my agenda here is pretty much transparent, and it would be a mistake to read more into my words than the words themselves. I just want to understand better how the LIMA grades are assigned.

I don't make posts like this until I have first done my homework, and exhausted the resources available from other parts of the BBHQ site. That said, NOTO has very nicely copied out what the site says about LIMA grades, to wit:

"Lima grade: Rating that evaluates how well a batter would fit into a team using the LIMA Plan. Best grades go to batters who have excellent base skills (BPV), are expected to see a good amount of plying time, and are in the $10 -$30 Rotisserie value range...."

Now this is a fine description of WHAT the LIMA grade means, generally speaking. This is what I meant in my first post, when I wrote: "I understand the broad idea--but I don't understand the process by which LIMA grades are assessed in the first place." But while this is a great description, broadly speaking, for what the grade is meant to convey, its not a very *precise* description of HOW one goes about assigning a grade.

I will really understand the meaning of a grade most fully when I have a reliable grasp of how I might go about assigning grades of my own, such that my grades reflect more or less well the grades assigned by other analysts. In other words, suppose I was the BBHQ staff writer who assigned these grades. What guidelines, if any, would you give me to distinguish an "A" hitter from an "A-" hitter, from a "B+" hitter? Would you basically say "take a look at the grades that the people before you have assigned, and go thou and do likewise?" Is it, that is, basically left up to the individual judgment of each writer? Or is there some more precise rubric?

Many thanks.

[hqforums]

The grading is not done by our analysts, it's all handled by a computer model. I'll try to describe it here as best as possible, using batters as an example.

It starts out with six separate tables, one each for Rotisserie value, walk rate, contact rate, PX, SX and plate appearances. Each table is tiered and the batter scores a certain number of points for his level on each table. So for instance, a 5% walk rate scores him a point, 9% scores three points, 11% scores 4 points and so on. This is done for each of the six tables, and the points and weights vary depending upon how important that element is (a batter can only get a maximum of 5 points for his walk rate, butr can score as many as 12 points for his PX level).

Finally, the scores for all six tables are combined and that total is used as a lookup function for the LIMA grade.

Bobby Abreu, as an example gets 5 points for his walk rate, 2 points for his contact rate, 5 points for PX, 5 points for SX, 12 points for plate appearances and -5 points for R$ (he's too expensive). That total of 24 points equates to a LIMA grade of "C".

For the tiered LIMA grades, we strip out the point total for R$ and use a fixed level for each dollar value break. This forces the model to assign a grade based on the player's skill and the dollar value we designate.

A bit confusing, I suppose, but if you think of it as a series of lookup tables, that's how it's done.

RON@HQ

[kehardwick]

Ron, this is outstanding. Thank you!