Building Fantasy Player Valuations?

I’d like to solicit the help of our community in building a useful fantasy player valuations guide. When we have the parameters set, I’ll code it and put it up on FanGraphs.

There are a couple goals here:

1. Building a useful and easy to use fantasy player valuation guide.
2. Full transparency in how all the rankings work.

I’ve dabbled in this a bit, so I will first give a starting point:

The worth of SB, HR, and all other categories, in Fantasy Baseball
How the Price Guide Works, Part I (Standard Scores)
How to Value Players for Rotisserie Baseball by Art McGee (Second Edition)

If I put things into steps, it basically seems like this is the general process:

1. Find the standard deviations and averages for each category for the appropriate player pool. (12 teams, 5×5 for example)

2. Using whatever projections, create z-scores for each player for each category.

3. Add up the individual category z-scores for each player.

4. Set position eligibility for each player.

5. For each position, take number of roster eligible players and adjust the worst player in the group to 0, while re-adjusting the rest of the players.

6. Based on the full pool of money to be spent and sum of position adjusted z-scores, assign dollar values to each player. (If you’d like to manually assign a split to hitting/pitching, do this here).

Most of these are pretty straightforward, but step 1 seems to be where there is the largest amount of disagreement.

How do you choose the player pool for averages and standard deviations? Do you use last year’s stats? Do you use projected stats? Do you use iterations? Do you use empirical data from similar fantasy leagues?

Then there’s the question of where ADP or Average Auction Value comes in, and how to use that data to try and further tailor your picks.

What about points based leagues?

How does removing a player from the draft pool impact the rankings and how do you handle that?

Feel free to tackle all these questions and point out additional issues in the comments. I’ll of course continue to participate with I’m sure plenty of additional questions and comments.





David Appelman is the creator of FanGraphs.

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Jason Collette
13 years ago

For #1, I prefer to use at least the last 3 seasons to rule out any wild flukes in a category where someone ran away with steals or saves, etc. If the league is a long-standing one, such as Tout Wars, I’ll go back a good five+ seasons.

jomuca
13 years ago
Reply to  David Appelman

David,

Sorry, I should have noticed that. I’m glad you’re aware of his work. If you’re planning something bigger and better than what he’s done, you’re going to make a lot of people happy.

jomuca
13 years ago
Reply to  David Appelman

Oops, this was meant to go below, concerning Mays Copeland’s “Price Guide.”

Jason Collette
13 years ago
Reply to  David Appelman

My own leagues are easier to pull. However, working for a company that runs leagues also allows me the luxury of pulling a variety of similar leagues and checking to see how far off my own local leagues are.

First year leagues are too crazy to pull data from, especially if they are auction leagues because dollar values tend to be crazy in first year auctions.