ATG9 – Normalized Error Ratings

As of ATG5, all player cards (including pitchers) were normalized to 1970* error rates.

Since then, not sure how SOM is normalizing errors – it appears they adjust cards from much earlier eras (like pre-war and especially pre-1920), but do not adjust cards for more modern players. This has two effects:

#1: Error normalization is not consistent across all cards
#2: More recent seasons (especially since 1990) have an advantage since normalized errors would go up – in some cases a lot - for seasons since the 1970 (error rates have plummeted in recent years)

Good point.

The pre war era stat collection was not just less reliable and lower fidelity, but also reflected a different era's view of the game.

Ball hits the glove and it was an error. No matter that the 2B ran from straight up play to the SS side for a backhand. Too bad. Oh sorry, did we forget to grade out the rocks and divots in the ground? There's 4" crabgrass in the infield grass?
These days, it's a hit if it takes a bad hop because it was rocketed down third and would have been such a tough play.

That doesn't help answer what the right answer is. But one thing does.
The rating itself, at least for online SOM, only has meaning once it has a price on the card. SO I don't care how they are normalized, as long as they are priced using a normalized schema.