Weighted On-base Average
Every way of reaching base, weighted by how many runs it is worth.
What it actually is. Weighted on-base average. Every way of reaching base is weighted by how many runs it is actually worth, then scaled so the result looks like an on-base percentage and can be read on the same scale.
What a scout reads off it. It is on-base percentage with the fiction removed that a walk and a home run are the same event. If you only ever learn one advanced hitting stat, this is the one, because it is the fixed version of the number the game already reads.
Where the lines are. It is set to sit on the same scale as on-base percentage, so around .400 is excellent, .320 is roughly average and .290 is poor.
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