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physicsgeek42
12-24-2009, 12:16 AM
Hi all,

I'm fairly new to posting here, so I'm really sorry if this has already been discussed and answered anywhere.

I have seen a number of tables giving weights to various stats for various classes and specs. I really appreciate how concrete this makes gear decisions. There is however one practice in these tables that I have seen that I do not understand. That is the treatment of hit and expertise.

In tables, I usually see these stats given weights like any other, but this does not seem right. Whereas other stats are simply stacked for increased benifit, these stats are usually kept at hard cap, at least for dps classes. For this reason, I believe that the values assigned these are not entirely accurate. For instance, say a table values strength at 60 magical points, and expertise at 73. How is the expertise value obtained? In tanking, where expertise is rarely hardcapped and the value of reduced dodges/parries can be easily calculated, this makes sense. But for a dps? This is not a stat that should weigh like that. Imagine a set of expertise and hit stacked items past hardcap. Clearly this is not going to improve potential dps, even though it should by the table.

I would suggest that these values should be termed not from the value of expertise to dps, but from the value of other item points "freed up" to do other things. On this basis, what should it be? Should each point of hit be weighted the in terms of how much of the next best stat it could buy? For instance, should 40 hit be worth the same as 40 strength for fury warriors because removing 40 hit worth of gems would allow you to socket 40 strength? Or should there instead be a lesser value placed on these items, to reflect that in any real gear set, the hit or expertise added will free up item points that will probably be used for a less than optimal stats? Is there a way to average this effect?

Ultimately, I'd really just like to know what the general rule is for how these numbers are generated, and why. Thanks for your help!

Satorri
12-24-2009, 06:24 AM
I don't often read into many of the stat weighting tables, but I do understand to some degree how they are created.

The world of min/maxing dps is a matter of science and precision. With any given class you can prescribe a standard, optimized talent spec and matching rotation, and usually the key to execution is matching that rotation as sharply as you can.

Using that ideal rotation you should be able to predict how much of each move you will use in a given time span and how each stat will influence your total damage. Based on that set spec, and expected ideal output of moves you can calculate just how much each stat is contributing and voila, relative stat values.

If you are a math-minded person you can probably do well by going to the source material (and I'd be reluctant to trust someone's stat ratings if they didn't link to their work and assumptions) and checking through their numbers.


On hit and expertise, maybe I can shed some light into why they get lower values on an absolute equivalency.

Hit and Expertise govern your chance not to connect, right? That chance is relative to target level, and varies for spells and melee attacks. For that they are gate-keeper values. They will increase the value of your other stats, but only so far as they reduce the times where the other stats are wasted. With no hit rating at all, against a raid boss, your melee special attacks will miss 8% of the time. That could generally be used to say it is reducing the value of your Strength by 8% (though there are other factors and Strength is not applied directly, but let's keep it simple). If the hit-reduced value of Strength *still* adds more total dps than adding hit instead to not lose value from the stat, then there's no reason (from a min/max standpoint) to add hit rating rather than Strength.

The same works for Expertise, though only against melee swings of course. For certain classes this may make Expertise less valuable still as it will only affect specific values in your damage output.

I have not read deeply into the math, but it seems to be fairly common practice for Warrior dps to stack ArP and/or Strength in every socket (depending on where their values fall). I take this to mean that someone has done the math to show that even if you have a chance to not connect you still get more increase with these stats. And gear you get will have hit and expertise on it, so you will not be up against a completely unmitigated miss/dodge chance.

I hope that helps. I've started dpsing more seriously on one of my DKs so I'm thinking I may actually do a comparison of this sort in the DPS forum. =)

wazdaa
12-24-2009, 09:59 AM
dps is just my os so i'm not to much into stat weights, but as far as i know simcraft (what EJ uses and what most ppl just copy paste) calculates it by doing the following:

you give a preset. then the sim adds 100 str and sees how much dps that would add, same for adding 100 haste rating, 100 agi, 100 ArP, ...
then it calculates how much adding 1 str, 1 agi, 1 ArP, ... would gain you in dps this you can use as stat weight, but often it's normalised so that 1AP=1stat weight.

hit and expertise however are calculated different. rather then the dps gain you'd get from adding them, they are calculated by the dps loss you'd have by losing em.

think this answers your question as they do it exactly as you asked. you can see if losing hit/exp in favour of strenght or any other stat would be benificial for you.

physicsgeek42
12-28-2009, 08:02 AM
Okay, so this is starting to make a little more sense. I guess I just assumed that in any practical situation, hit and expertise would be capped because I assumed that a gear set would be chosen and gemmed as such. It didn't occur to me that it might be beneficial to run below soft cap. Thank you!