What stats/item modifiers should I be focused on for a Monk on Inferno?

Problems with the accepted answer:

1. The fact is, there is no "too slow" as long as you survive, especially as a monk. In Inferno, if you do not kill an elite fast enough, after a few minutes a skull and crossbones will appear over your head and theirs, and you will quickly die because it does a lot of damage over time. To progress through Inferno, you need to keep stepping up your damage through each act. Also, surviving isn't actually that important - if you are playing a little beyond your gear, you can still farm reasonably effectively by dying strategically. If you can take one minion or champion down by a third of it's health before you die, you can probably clear the elite pack. Damage one by a third, die, do another third, die, kill them, die. If you're still having trouble, wait in town for 3 minutes and your death timer will reset, and you can repeat this process until the elite pack is dead. Note that this strategy is pretty slow, and you're better off going back to the previous act, but it can be effective for a particularly difficult elite in an area you can otherwise manage well.

2. Try to focus on items with physical resistance if you really want to build tanky. Physical resistance items are arguably acceptable for other classes, but are specifically bad for Monk. If you want to gear up economically, you need to be using the One with Everything passive, and you should make sure all your single resist are the same. Physical resist is actively sought by other classes, and is hence more expensive, and gives the exact same benefit as every other resist type as a Monk with One with Everything. You should pick Cold, Lightning, or Arcane - these are the cheapest.

3. Resistance against impairing effects is good, as is damage against melee attackers. Resistance against impairing is good, but damage against melee attackers is useless. Elites in Inferno sometimes have more than 1,000,000 Health (sometimes much more), and even if you had iLvl 63 gear with the highest possible stat of this affix on every item, you'd get about 25,000 damage on hit. Assuming that lvl 61-65 monsters don't reduce this damage at all (very unlikely), an elite would have to hit you 40 times to kill himself. Realistically, even if you try to get this stat on most of your items, you'd have a hard time hitting 5,000 total, and they would take 200 hits to kill themselves. Most fights are over before you are hit even 20 times by single elite. Obviously, it's better than nothing at all, but not by much.

You should have the highest dps weapon you can afford. I find the game is much more fun with higher attack speed, so consider attack speed rings/amulets to make it a speed you like. The dps number on your weapon is extremely important to all damage calculations, and it's worth it to get a weapon with otherwise useless stats if the dps is very high. More damage on your weapon means you can have much more vitality in your gear instead of dex for the same amount of damage.

After that, balance Dex for damage with Vitality and All Resists. If you want to save money, specialize in one resist type, and use the Passive that makes that all resists. Often you can find, say, Dex/Vit/Arcane items priced as if they were Dex/Vit, even when the arcane is 50+, so you can find great deals.

Ideally, you want to do some math to figure out the relative value of different stats offensively and defensively, but here are some rules of thumb just based on my current equipment and the math I've done - these relate to your overall defensive capability, as you can see the Damage stat on your paperdoll. There is no equivalent shown for defense.

• Strength and Armor are about half as good as Dex for defense.
• Int is better than Strength or Armor, by about 50%.
• Vitality is almost 3 times as good as Dex.
• Resistance is about 7 times as good as Dex, or a little more than twice as good as Vitality.
• Life Percent increase is the best defensive stat per point, but only comes in very low amounts. It makes an item much better, but usually shouldn't be taken at the expense of another defensive stat.

So, when you evaluate for defense, think about these relative values - they will vary depending on your setup, however, and the math gets pretty complicated.

Other than Dex, consider Crit Chance and Crit Damage. On my gear, just for a frame of reference, these would all add about the same amount to my damage (about %2.4 - I have fairly low crit):

• %5 Critical Hit Chance
• 36 Dexterity (improves defense as well, tho)
• +%50 Critical Damage

Crit Chance and Damage essentially get multiplied together, so the higher both are, the better. In my experience, so far, 36 more Dexterity is far cheaper than %5 Critical Hit Chance - your mileage may vary. A decent rule of thumb might be to treat Crit Damage as half a point of Dexterity, and Crit Chance as 5 points of Dexterity.

Here are some nice formulas (proportions, no percents, lvl 60):

Terminology:
"Bonus" references in increase by a fixed amount
"Multiplier" references increase by a percentage, converted to proportion
You need to add 1 to the sum of multipliers before multiplying, as these
represent an increase.

Base Str/Dex/Int/Vit for Monk is 67/187/67/127

Vit = (127 + VitFromItems) * sum(VitMultipliers)
Life = (276 + Vit * 35) * sum(LifeMultipliers)

Str = (Base + StrFromItems) * sum(StrMultipliers)
Dex = (Base + DexFromItems) * sum(DexMultipliers)

Dex
<100     BaseDodgeChance = Dex * 0.001
100-500  BaseDodgeChance = 0.10 + Dex * 0.00025
500-1000 BaseDodgeChance = 0.20 + Dex * 0.0002
>1000    BaseDodgeChance = 0.30 + Dex * 0.0001

multiply in each dodge bonus separately, eg.
Dodge = 1 - (
    (1 - BaseDodgeChance) * 
    (1 - EvasionMantraDodgeMultiplier) * 
    (1 - GuardiansPathDodgeMultiplier)
)

ArmorBeforeMultiply = ArmorFromItems + Str + OtherArmorBonuses
EffectiveArmor = ArmorBeforeMultiply * sum(ArmorMultipliers)

ResistBeforeMultiply = ResistFromItems + OtherResistBonuses
EffectiveResist = ResistBeforeMultiply * sum(ResistMultipliers)

Int = (Base + IntFromItems) * sum(IntMultipliers)
EffectiveInt = Int + 10 * EffectiveResist

DodgeEffect = 1 - Dodge
ArmorEffect = 1 - 1 / (1 + 50 * EnemyLevel / EffectiveArmor)
IntEffect   = 1 - 1 / (1 + 50 * EnemyLevel / EffectiveInt)

EffectiveHealth = Life / ArmorEffect / IntEffect / DodgeEffect
MonkMeleeEffectiveHealth = EffectiveHealth / 0.70