From Diablo Wiki
Effective DPS is a term for a character's actual DPS, akin to what a DPS Meter would show if there was such a feature in Diablo 3.
Effective DPS is meant as a contrary or corrective to Sheet DPS, which is what displays in the character window in-game, but which can give a very inaccurate picture of a character's actual damage output. Sheet DPS does not include bonus properties such as +damage to Elites, +damage to individual skills, and +damage to Elemental skills, all of which can double or triple a character's effective DPS above and beyond the Sheet DPS.
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