Item Levels Revisited

Kazanir · 06/06/07, 12:23 PM

The most current version of my item level calculator is available at http://wow.virakar.com/stats/itemlevel.html. Please feel free to distribute the link.

The calculator has been updated to refresh the item level each time one of the stat fields is changed. Also, the socket calculation has been changed to value each socket as 10 of a blank stat, stacked, so that 3 sockets are worth 30 of a single dummy stat/rating. Meta gems are valued at double this. This is of course a rough estimate, as no one from Blizzard has ever given any good hints as to how sockets fit into the item value formula. It seems like this method should be highest reasonable value of sockets (including a stacked value and assuming epic gems available for +10 stats per socket.)

To wit, I examined Vashj loot after noticing that I was getting a lot of low values looking through SSC stuff:

Runetotem's Mantle
Given ilvl 138, calculated ilvl 131.6

Coral Band of the Revived
Given ilvl 138, calculated ilvl 138.5

Kraken-heart Breastplate
Given ilvl 138, calculated ilvl 137.4

Serpent Spine Longbow
Given ilvl 138, calculated ilvl 135.6

Ring of Endless Coils
Given ilvl 138, calculated ilvl 124.2

Most things come up very close to their intended item level, with one glaring outlier. Now let's look at the socketed loot:

Belt of One-Hundred Deaths [S]
Given ilvl 138, calculated ilvl 129.0

Cobra-Lash Boots [S]
Given ilvl 138, calculated ilvl 128.7

Glorious Gauntlets of Crestfall [S]
Given ilvl 138, calculated ilvl 128.3

Ring of Endless Coils [S]
Given ilvl 138, calculated ilvl 124.2

Vestments of the Sea-Witch [S]
Given ilvl 138, calculated ilvl 135.0

These results would lead me to conclude that sockets are being somehow valued much higher than my assumptions, except for the last piece of loot being reasonably close to the intended item level, when the previous 4 aren't even close.

Let's look at some more SSC loots:

Ancestral Ring of Conquest
Given ilvl 128, calculated ilvl 122.7

Blackfathom Warbands [S]
Given ilvl 128, calculated ilvl 117.0

Bloodsea Brigand's Vest [S]
Given lvl 128, calculated ilvl 122.2

Boots of Courage Unending
Given ilvl 128, calculated ilvl 115.9

Boots of Effortless Striking
Given ilvl 128, calculated ilvl 116.9

Boots of the Shifting Nightmare
Given ilvl 128, calculated ilvl 119.1

Brighthelm of Justice
Given ilvl 128, calculated ilvl 123.5

Choker of Animalistic Fury
Given ilvl 128, calculated ilvl 120.1

Fathomstone
Given ilvl 128, calculated ilvl 120.2

Frayed Tether of the Drowned
Given ilvl 128, calculated ilvl 120.9

Girdle of the Invulnerable [S]
Given ilvl 128, calculated ilvl 114.6

Girdle of the Tidal Call
Given ilvl 128, calculated ilvl 117.4

Glowing Breastplate of Truth
Given ilvl 128, calculated ilvl 121.8

Gnarled Chestpiece of the Ancients
Given ilvl 128, calculated ilvl 123.4

Grove-Bands of Remulos
Given ilvl 128, calculated ilvl 123.4

Illidari Shoulderpads [S]
Given ilvl 128, calculated ilvl 115.7

Luminescent Rod of the Naaru
Given ilvl 128, calculated ilvl 121.1

Mallet of the Tides
Given ilvl 128, calculated ilvl 112.1

Orca-Hide Boots [S]
Given ilvl 128, calculated ilvl 113.4

Pauldrons of the Argent Sentinel
Given ilvl 128, calculated ilvl 107.6

I could go on but I'm getting tired. Does anyone see any patterns to this mess? Have they changed the entire item level formula? Some things (including the non-socketed Vashj loot and a bunch of the Black Temple loot) indicate no, but these results indicate that many things are still either screwy or not well-understood by the playerbase.

I'm really not sure what else to say since I don't know where to go from here, to be honest.

Thoughts?

Lactose · 06/06/07, 12:26 PM

A quick thought might be something to do with amount of sockets (not stacking additively?), or colour having different values?

Kazanir · 06/06/07, 12:28 PM

Both of those are possibilities. Note though, that the vast majority of SSC loot I looked at is unsocketed and still coming up significantly lower than the given level of 128.

Suesse · 06/06/07, 1:04 PM

When the 2.1.0 gear buff happened how did they increase the stats on gear? Did some guy manually go through and buff every stat on every item? Or did he just change the item level and the stats all increased by themselves. I'll assume that they had to go over every item after automation just to make sure no mistakes happened.

I think it may be time to perform some massive statistical analysis.

talzar · 06/06/07, 1:15 PM

Hasn't Blizzard said in the past that the amount of deviation between stats affects how many "item points" they consume?

For instance an item with
30 str
30 int
30 agi

will not require as many item points as an item with
20 str
20 int
50 agi

Not just because the agi is a larger number (thus consumes more item points the larger it gets) but because the difference between the 50 agi and other stats being so large. Maybe I'm stating something that everybody always knew, but it was new to me.

I don't know the formula you're using to calculate the derived level.

Elendril · 06/06/07, 1:17 PM

I'd venture to say that it's very likely that the itemization formula itself changed with the massive 2.1 changes and not just the ilvls of various items, given the scope of the changes.

Kazanir · 06/06/07, 2:08 PM

Originally Posted by talzar

Hasn't Blizzard said in the past that the amount of deviation between stats affects how many "item points" they consume?

For instance an item with
30 str
30 int
30 agi

will not require as many item points as an item with
20 str
20 int
50 agi

Not just because the agi is a larger number (thus consumes more item points the larger it gets) but because the difference between the 50 agi and other stats being so large. Maybe I'm stating something that everybody always knew, but it was new to me.

I don't know the formula you're using to calculate the derived level.

If you don't know the basics of the item level formula (http://www.wowwiki.com/Formulas:Item_Level) then please don't comment.

I'm using the well-known formula that was derived by Hyzenthlei ages ago, and confirmed to some extent at the first Blizzcon convention and by the introduction of the combat rating system. The code (if you can stand my hackish, self-taught Javascript) is viewable in the HTML page header, but you'd be better off with the WoWWiki page if you want to learn how it works. Leastways, I'd like for this to be a discussion about the formula and itemization stats for people who already know the basics, not a primer for those new to the subject.

Originally Posted by Elendril

I'd venture to say that it's very likely that the itemization formula itself changed with the massive 2.1 changes and not just the ilvls of various items, given the scope of the changes.

That was my initial guess as well as I was just testing the new page against some random SSC items and everything was coming out so gnarly. However, take a look at these BT loots:

Blind-Seer's Icon
Given: 141 Calc: 143.0

Band of the Abyssal Lord
Given: 141 Calc: 139.8

Chestguard of Relentless Storms
Given: 141 Calc: 139.3

Blade of Savagery
Given: 141 Calc: 138.8

Blade of Infamy
Given: 141 Calc: 138.8

Enchanted Leather Sandals
Given: 141 Calc: 136.3

Black Featherlight Boots
Given: 141 Calc: 131.6

Blue Suede Shoes
Given: 141 Calc: 134.7

Some of them are right on the money where almost NONE of the SSC loots match their "given" item level, all with the "old" formula. I'm looking for patterns and not seeing much of anything, although this isn't exactly a grizzled veteran's statistical analysis.

Kazanir · 06/06/07, 2:12 PM

Edit: Server hates me.

Kazanir · 06/06/07, 2:29 PM

Edit: Server hates me.

Grayson Carlyle · 06/06/07, 6:02 PM

I think the formula changed with 2.0. The most obviously evidence of this is random stat items. They are what sparked Hy to figure out a formula in the first place.

In 2.0, new uncommon items with randum suffixes using the "old" formula are overbudget, and get more-so as their ilvl increases. Similiar rare items start very close to the values the "old" formula gives, while falling behind at higher levels, and finally, epic items with a random suffix are noticably underbudget, suggesting the actual budget available may have changed.

With nothing more than anecdotal evidence, I'd also suggest that the mod exponent has increased, as items with fewer stats tend to be quite a bit underbudget relative to other items their level with many stats, Ragesteel set for example.

And then there are items like Devilshark Cape which just make you go "wtf were they thinking?"

Wensleydale · 06/07/07, 5:33 AM

Originally Posted by Grayson Carlyle

In 2.0, new uncommon items with randum suffixes using the "old" formula are overbudget, and get more-so as their ilvl increases. Similiar rare items start very close to the values the "old" formula gives, while falling behind at higher levels, and finally, epic items with a random suffix are noticably underbudget, suggesting the actual budget available may have changed.

I've never seen anything to suggest that random-suffix items no longer follow Hyzenthlei's original formulas. I just double-checked now on a couple random items: Archmage Robe (green chest) and Abyssal Cloth Footwraps (blue feet). First one "of the Owl" has a calculated iValue of 131.43, and an expected value of 131.77: spot-on. The second one has a calculated iValue of 109.53 and an expected value of 111.42: increasing the stats on the shoes from +30/+30 to +31/+31 puts them over budget, so once again, spot-on stat allocation. A while back I also checked all the specific green chestpieces from Outlands, and nearly all of them conformed to the item budget perfectly, although one or two looked like they used the old Stam budget, and a couple were just weird. I don't think the budget formula has changed, I just think the item designers are fucking up or disregarding the formula.

Edit: Sockets are very strange, and sometime I'd like to try and nail down the value of sockets. It's pretty clear that not all sockets are worth the same amount: I think there are some items out there with identical iLevels and types of stats, but different socket colors and different quantities of the stat (like, the blue-socketed item being identical to the red/yellow-socketed item except the blue-socketed one had 6 more agility). But it's impossible to reverse-engineer the item formula when Blizzard doesn't seem to be following it!

RK · 06/07/07, 8:24 AM

If Black Temple uses the original loot formula while tier 4 and tier 5 have an upgraded loot formula, it strongly supports Gurg's theory that Black Temple was not re-done after they decided to change tier 4 and tier 5 itemisation.

It's also a further suggestion at what went "wrong" as far as Black Temple loot being unnecessary to kill Illidan. Under the old tuning, tier 4 and tier 5 probably wouldn't have been good enough, so even Nihilum would have had to farm BT gear for a bit. But revised SSC/TK loot IS good enough.

Looks like it will be necessary to run an analysis of a bunch of new items against each other to determine the new formulae.

Kazanir · 06/07/07, 11:48 AM

Let's look at some randomly enchanted gear from pre-patch:

Illidari Cloak of Stamina
Given: 103; Calc: 97.44

Illidari Cloak of the Bear
Given: 103; Calc: 101.5

Illidari Cloak of the Beast
Given: 103; Calc: 105.7

Dragonhawk Bands of Stamina
Given: 120; Calc: 121.1

Dragonhawk Bands of the Bear
Given: 120; Calc: 126.5

Dragonhawk Bands of the Beast
Given: 120; Calc: 127.0

Interesting. Now for some new blues from post-patch. These are less interesting because they are always 3-stat suffixes, no 2- or 1-stat variants.

Skystalker's Leggings of the Beast
Given: 115; Calc: 111.5

Skystalker's Boots of the Beast
Given: 109; Calc: 105.1

Skystalker's Bracers of the Beast
Given: 115; Calc: 111.1

This looks from a few examples that it might be consistent enough to warrant a spreadsheet, but I'm not sure if a gear spreadsheet exists that accounts for all the possible random item values?

Wensleydale · 06/07/07, 2:44 PM

I think your calculator's off by a bit, Kazanir. Edit: well, it's off from the original Hyzenthlei formula, which wasn't pin-point perfect to begin with.

I did the Archmage Robe of the Owl (linked in my last post: 36 int/spi green chest) by hand with the original formula:

itemValue = [(230 * 36)^1.5 + (230 * 36)^1.5]^(2/3)/100

and plugged that into the expected-value formula of Value = (iLevel * 1.21 - 9.8) * SlotMod. That gives me a calculated iLevel of 116.72, exactly in line with the true iLevel of 117. When I choose:

Slot: chest
Quality: uncommon
Intellect: 36
Spirit: 36

your calculator gives me 118.29.

I also tried the Dragonhawk Bands, and my numbers come out closer to yours: 125.25 for "of the Owl", and 126.89 for "of the Beast" (I gave Stamina a 153.33... weighting). If those bracers had +20/+20 stats instead of +21/+21, they would be perfectly in line with the formula--119.85 calculated iLevel. The iLevel 117 random green bracers are +20/+20, and the 114 bracers and 111 bracers are +19/+19, so I guess they'd all come out a bit over-budget according to our formula.

I think the discrepancy between your calculator and mine is just due to rounding. Hyz's original formulas only had two significant figures for all of the constants, and your Javascript calculator has manipulated those constants and truncated them down to two sig-figs once more. Without better precision, we may have to say that any item within 5% of the expected iLevel is "close enough."