How to use R/L splits ("balance")

[dkoulomzin]

Does anyone know how to value the splits indicators given on each card? You know, like 3L, 2R, E, etc. What is the difference in BA or SLG or OBP to expect from these?

[YountFan]

It is a secret formula used by SOM. Not sure how it is calculated, or how accurate of a guide it is. I'd use it as a relative guide, not some absolute. Is the balance rate normalized to all the players in the 80's game, normalized to the actual season, or something else.

[Outta Leftfield]

I'm sure you've picked up on the fact that the higher the number (say, 9R) the stronger the platoon advantage. Ultimately, as YF says, it's just a kind of summary indicator (it's got to balance complex factors like BA, BB, HR, doubles and triples, etc.)

One thing that might be overlooked is that the number has a different significance depending on the percentage of at bats the player has against each side. For example, let's say you're looking for a cheap LHB to use in a platoon role. So you look at a guy like Ron Bush. He's a .748 OPS 5R lefty for .75M. But with Bush that .748 OPS is all you get if you bat him against RHP. He averaged about 96% of his AB against RHP--so there's no bonus for platooning him. Those ARE his platoon numbers, since he never hit LHP. On the other hand, what about Luis Polonia. With his .739 OPS 4R, he might not look as good as Bush in a platoon role vs RHP. But Polonia had more AB's vs LHP than Bush did, so his cards in most years will probably give him more value vs RHP than Bush would. The more AB's he had vs LHP, the more value he'll have vs RHP. So it's always a good idea to check out a player's proportion of AB's against each side.

[Semper Gumby]

Use www.retrosheet.org to see how the player's splits faired.

Pretty decent source