Stat scaling is an interesting, if rarely discussed, subject. It’s the reason why stat weights vary from tier to tier, and why gearing can be such a headache at times.
For the most part, stats actually scale in a very understandable manner: linearly. For the math inept among us, something which is linear is merely a straight line of some sort which can be reduced to the equation y=mx; in this case, with y being dps gained, x being the specific stat in question, and m being some sort of coefficient depending on the stat’s worth. The more valuable a stat is, the greater m will be, and vice versa. M is essentially that stat’s weight – simply normalized depending on the AP:DPS ratio of your spec/gear level. If a stat scales linearly with itself, it doesn’t matter how much of that stat you already have – you’re still going to get Y dps for every X of that stat. Period.
It is important to note that, in this context, we’re talking absolute dps gained, not the relative amount. E.g, if 10 strength gives you 50 dps, and strength scales linearly (it does), then it will give you that same 50 dps regardless of pre-existing strength amount. That said, that 50 dps may be a 1% dps gain when you have 100 strength to begin with, and only a 0.5% dps gain when you have 200 strength to begin with. Just something to keep in mind.
With that out of the way, which stats are linear? Attack power, strength, crit rating, and mastery rating.
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