Check My Maths (Frost Resistance)

[Meat]

Hey all,

So I was recently wondering what would happen if I stacked frost resistance and how that would work out with other % modifiers such as resilience and effects like stoneform, hand of sacrifice etc.

So, if I were to use the following:

Fur Lining - Frost Resist
Gyrofreeze Ice Reflector
The Frozen Eye
Frost Resistance (Passive Racial)

That would put me at 190 Frost Resistance, and if I factor in my 28.5% resilience and a 10% reduction from Stoneform, I do the following calculation:

((((28.57/70)*190)*1.285)*1.1)

However... this works out to be a ridiculous 109.6% reduction from Frost spells?

I know this can't be right but I don't know where I'm going wrong... if you could clarify this it'd be great!

Many thanks,
Meat

 

[Esotra]

I personally had trouble learning my times tables, But holy jumpin' poopballs.

For one, It doesn't stack like that, it's not 28.57% from 70 resistance, another 28.57% resistance from another, and so on. It scales down dramatically, exactly how much/quickly, i cannot recall.

As for stoneform, 10% Reduced damage doesn't stack like that either, it won't stack with 30% armor, 30% resilience, and 10% from stone form to equal 70%.

I'll try to check the calculations in a bit, i'm rather kaput, per se.

 

[mrdoobry]

I believe the mistake you are making is you think the reductions are additive rather than multiplicative.

I think the game takes each reduction in turn and applies the reduction on the outstanding amount (do not quote me on this).

So to keep it pretty simple let us use your numbers to apply to it:

You have 28.57% damage reduction from resilience.

With 190 Frost Res you have (at level 70) 52.05% damage reduction from sources of Frost damage. However, most casters will be running with the minimum Spell penetration of 70 so it will leave you with an effective Frost resistance of 120 which is a 40.68% damage reduction.

Stoneform providing 10% overall damage reduction whilst active.

Let us take a theoretical scenario of you getting hit with a Frostbolt (source of frost damage) for 10000:

Game would consider the reduction from resilience to reduce the 10000 hit by 28.57% to 7143 damage.
Game would then apply the frost resistance reduction to the 7143 damage (not additional to the resilience reduction on 10000) of 40.68% to leave 4237 damage.
Game would then apply the 10% damage reduction from Stoneform from the 4237 damage to leave 3183 damage.

So the final damage would be 3183 from a 10000 hit for a grand sum of approximately 68.17% damage reduction overall.

Hope this helps.

 

[Hellmuth]

There was a similar post a few months ago who made a max frost resist gear set. Apparently he pwned mages. You may want to wait until MoP because they are messing with this resistance mechanic and your competitive advantage may go away.

 

[Narox]

you're missing the point, that frost resistance doesnt reduce every single dmg you take. It's an average damage reduction, which means it may reduce the dmg of frost spell or you resist the whole spell. On the other hand, if you have bad luck, it wont reduce any damage, because nothing of the spell gets resisted. Which means if you resist with for example 50% frost average dmg reduction, it will most likely reduce it even more than 50%. And sometimes, you wont resist anything of the spell, so that the average damage reduction balances to an average of about 50%.

You cant use frost resistance as a fix mathematical number for your calculations, because the dmg reduction depends on your luck

 

[mrdoobry]

Obviously most people are aware of the resistance mechanic and partial resists. It is showing the average, and the original question was about the maths for working out the total reduction from all sources.

Most up-to-date formulas and mechanics can be found here:

Cata Combat Ratings @ Elitist Jerks