What's new? | Help | Directory | Sign in
Google
epgp
effort points/gear points loot system for World of Warcraft
  
  
  
  
    
Search
for
Updated Nov 08, 2007 by evlogimenos
Labels: Featured
WhatIsEPGP_v2  
EPGP: Effort Points, Gear Points

Introduction

EPGP is based on the concept of Effort Points and Gear Points. Effort Points quantify the effort each member put towards the (common) guild goals and Gear Points quantify what each member got back in return. Loot priority is computed as the quotient of the two; priority (PR) is equal to EP/GP.

In a sense EPGP is like zero sum, but without all the need to rebalance the system, or impose taxes to give points for other effort put into the guild. Zero sum awards GP/N points to each player for each item dropped (GP the value of the item and N the number of players in the raid) so that the sum of all points for the members of the guild is zero. EPGP on the other hand is by definition self balanced since priority (and hence chance to receive loot) is directly proportional to the effort you put and inversely proportional to the rewards you got. It is also much more flexible than zero sum since it doesn't require a specific balance point (sum to be equal to zero for example). As such points can be awarded for almost anything without any taxation or over complicating the system (see below). Also another problem with zero sum is the random value of each boss. A boss kill is a boss kill and the effort to kill it is the same no matter if it happened to drop 1 or 2 epics. With zero sum since the amount of effort points the members get is proportional to the loot dropped which is definitely not representing fairly the effort each member puts in the guild.

EP can be awarded through a multiple activities:

GP points are accounted though some other set of action:

Clearly each guild can choose to use any combination (or even come out with its own point assignment) of the above points. Assignment of points for each activity/action is not something that EPGP tries to solve. This is solely left to the guild management, as it is out of the scope of the core of the system (and is also the case with many popular loot systems).

Another twist in EPGP, that makes it different than other loot systems is the fact that EP and GP decay over time. The decay can be set by the guild master (it can also be disabled if it is set to zero). With a decay of N%, after each raid the guild participates in, each member gets her EP and GP reduced by N%. This eliminates EP (DKP) hoarding.

Because of the fact that EP decays over time, we can use a simple metric to estimate attendance: Min EPs. Given a value for Min EPs we choose to give PR = 0 to those that have less than Min EPs. As an example, assume a guild where about 500 EPs are awarded per member per raid and a Decay of 10%. If Min EPs is set to 1300 then a member needs to be in at least the last 3 raids to be eligible for loot (500+450+405), or the last 4 raids before the last one 450+405+365+329. This is arguably a better measure than attendance, as attendance is a somewhat loose criterion: if a member came to a raid for 1 hour only and the rest were in it for 4, do they all count as the attended the raid? Since EP measures the effort of each member, having a Min EP puts the cut-off at an effort point which will work both for new members and old members. An old member that is idle for a long time will loose EPs gradually so she might get lower than Min EPs which makes her ineligible for loot. A new member starts with EP equal to zero so he needs to attend some raids in order to get his EP above Min EP to be eligible for loot.

Another way to combat people with 0 GP skyrocketing on the PR meters (trials or inactive members that just became active) is with Base GP. With Base GP set to X everyone's effective GP becomes X + Individual GP. Effective GP will never go below X. Using Base GP has a major ramification:

Of course you can use both Min EP and Base GP (or just one of the two).

GP Values

EPGP also adds a tooltip line to items displaying the GP value of the item. The GP value is computed using the item level and the equipping slot of each item as follows:

GP = item value2 x 0.04 x slot value

Item value is computed using the following:

Item Quality Item value
Uncommon (Green) (ilvl - 4) / 2
Rare (Blue) (ilvl - 1.84) / 1.6
Epic (Purple) (ilvl - 1.3) / 1.3

Slot mod is given by the following table:

Equipping Slot Slot value
Head, Chest, Legs, 2H Weapon 1
Shoulder, Hands, Waist, Feet 0.777
Trinket 0.7
Wrist, Neck, Back, Finger, Off-hand, Shield 0.55
1H Weapon, Ranged Weapon, Wand 0.42

Just giving some examples, using the above formula gives the following GP values for the following items (mainly priest items).

Chest pieces:

Staves:

As you can see this model of assigning values to items, scales well between rare and epic items alike. In the above list there are blue items that are of better quality than epics and their GP value correctly models this fact.

Specifics

Each member starts with EP = 0 and GP = 0. As such PR = 0. As EP are awarded PR goes up and as GP are awarded PR goes down. Let us look at an example. Assume 3 members A, B and C, EP per raid 10, GP per item 10, and DECAY_P = 10. Also assume that member A attends all raids, member B and C only 2 out 3.

Here's how EPGP look like before the start of raiding:

Member EP (Last Raid+Previous Raids) GP(Last Raid+Previous Raids) PR
A 0+0 0+0 0
B 0+0 0+0 0
C 0+0 0+0 0

In the first raid the all attend, and A and B receive loot:

Member EP (Last Raid+Previous Raids) GP(Last Raid+Previous Raids) PR
A 10+0 10+0 1
B 10+0 10+0 1
C 10+0 0+0 10

Notice that the when GP is 0 when computing PR we take it as 1. In the start of the second raid EP and GP will decay by DECAY_P%. The standings will look as follows:

Member EP (Last Raid+Previous Raids) GP(Last Raid+Previous Raids) PR
A 0+9 0+9 1
B 0+9 0+9 1
C 0+9 0+0 9

In the second raid all participate so the next to receive loot is C and lets say that B receives loot as well (member B is tied with member A so they roll):

Member EP (Last Raid+Previous Raids) GP(Last Raid+Previous Raids) PR
A 10+9 0+9 2.1
B 10+9 10+9 1
C 10+9 10+0 1.9

In the beginning of the third raid we decay all EP and GP again. The standings table will look as follows:

Member EP (Last Raid+Previous Raids) GP(Last Raid+Previous Raids) PR
A 0+17 0+8 2.1
B 0+17 0+17 1
C 0+17 0+9 1.9

Notice that even though A and C attended the same raids and received the same loot A's PR is higher than C's. This is because A received an item earlier than B so that item's value decayed for more time than B's item.

Now in the next raid only A participates and receives a piece of loot:

Member EP (Last Raid+Previous Raids) GP(Last Raid+Previous Raids) PR
A 10+17 10+8 1.5
B 0+17 0+17 1
C 0+17 0+9 1.9

Time for the next raid. The starting table will look as follows:

Member EP (Last Raid+Previous Raids) GP(Last Raid+Previous Raids) PR
A 0+24 0+16 1.5
B 0+15 0+15 1
C 0+15 0+8 1.9

Everyone participates. Next in line to receive loot are C and A. And they do in which case the final table will look like this:

Member EP (Last Raid+Previous Raids) GP(Last Raid+Previous Raids) PR
A 10+24 10+16 1.3
B 10+15 0+15 1.7
C 10+15 10+8 1.4

Up to this point A received 3 pieces of loot, B and C received 2 pieces.

Problems/Solutions

EP hoarding

This problem is non-existent in EPGP because of the use of the EP and GP decay. Only temporal EP and GP are accounted. So the latest you "use" your PR lead the least amount of benefit you get out of it. And the earliest you take an item, the faster its value will decay.

New members vs Veterans

Because of the decay, new members become equal under the system much faster. EPs decay over time so with a 10% decay in about 15 raids a veteran has about the same EP as a new member (if they both attended the same raids). The only barrier to entry for new members is reaching Min EPs in order to be eligible for loot.

Members that are geared up vs members that are not

Members that are geared up already will end up with the highest PR possible and will have first priority over a new (and possibly rare) drop. This will satisfy these members. Members that are not geared up already will end up getting loot in most raids which will keep their priority low. So they will still gear up but they will not threaten members that wait for a special piece to drop in order to get their satisfaction as well.

Complexity

Unlike Zero Sum with taxation, which is very similar, there is no need to rebalance when members join/leave guild, and no changes in tax/decay because of more tries on new content. The reduced complexity of the system allows more people to understand it, which keeps the queries to the guild master low and member satisfaction up.

Hard to assign item values and boss kill/tries values

Because effort points are decoupled from effort points it is easier to assign "good" values for each category. Guild Masters/Officers can focus on balancing different boss kill/tries, materials farming rewards separately from item values. If you notice in the above example nothing would change if each raid was awarding 987 EP and each piece was worth 123 points. Balancing rewards and items is extremely hard; balancing them in isolation is quite simpler.

Randomness on boss value in zero sum

Zero Sum's major flaw is that for the same encounter, you might end up getting more or less points, depending on the loot (which is random). This introduces a major cause of unfairness to the system, since the same boss, which requires the same effort, is worth more in some runs and less in others. In EPGP each boss awards the same EP every time, adding to the fairness of the system.


Comment by apsmith12, Aug 28, 2007

Members that are geared up vs members that are not

contradicts

EP hoarding

Comment by ebombar, Sep 05, 2007

How can we change PR from EP / GP to EP - GP ?

we don't want to use PR system this way.

Comment by trankillity, Sep 05, 2007

EP - GP will mean that people can hoard and defeats the purpose of the system. Even with decay, the values would just keep rising. It would mean that new members would take muuuuuch longer to get loot.

Comment by prodigy86, Sep 19, 2007

This system is rigged imo. There's no difference between greed and need. I was ignorant of this and went ahead to greed some items only to realise I got punk'd. Also, items that NOBODY else wants and is about to get disenchanted should cost signifantly less to whoever needs it as it will just be wasted otherwise. Just my 2 cents.

Comment by ronaldkunenborg, Oct 02, 2007

Disenchanted items aren't wasted: you need the shards for enchants for guildmembers. Don't greed items. A shard and a usefull enchant is better than an item in your bank.

Comment by flurie, Oct 02, 2007

Hi Evlogimenos,

We've found great success with your mod. One thing we decided on a month or so in was a soft cap on GP. It's slightly different from your base GP system in that the soft cap only exists to calculate the PR of people whose GP is below the soft cap. The soft cap is such that it takes recruits about a week and a half to climb the list, and once players all have taken items, it looks pretty much the same. It can be a pain for members who reach the cap, as their PR starts to decay, but if they're at that point, then they're either at the top of the list anyway, or they're fair weather raiders, and they're about where they should be on the list.

Comment by founts, Oct 02, 2007

Prodigy86, the system isn't rigged, your MAster Looter is. We charge 10% of the value for secondary items or items that will receive less use (ie: Second set of t4 gloves for a resist set, when everyone in the raid already has the gloves. Instead of 259, we charge 25.)

The glory of this system is you can charge whatever you want, just type it in. Don't knock the system, knock who is running it if they don't have a clue how to =)

Comment by founts, Oct 02, 2007

Flurie, if you read the discussion group on EPGP, Evlogimenos has programmed in a base GP cap that isn't subject to Decay as normal gear points. It is in beta now, I am sure he will announce and explain how to work it once it is out of beta!

Comment by opeksen, Oct 09, 2007

Hi We have been using epgp about a month and still we couldnt decide the EP's for bosses , ontime, DKP's, and decay (per week, per raid, how much?) Evlogimenos Can you advice me? Thx

Comment by Isli.wow, Oct 14, 2007

Well I think one of the advantages of this system is that you don't have to put that much thought into how many points you award, as long as it is somewhat consistent and doesn't change too much over time. The system will work just the same whether you award 1 point per boss or 100 - just the average PR will be different.

As for decay it depends on how quickly you want to drop off old efforts and gear purchases.

Say you choose a rate of 10% then with every decay you lose 10% of your current EP and GP (your PR will not change however), so after 10 decays you have (100%-10%)10 = (1-0.1)10 = 0.35 = 35% of your original points left.

If you decay weekly with these numbers you could take 10 weeks off and still have 35% of your EP and GP - if you decay daily you'd reach that point after 10 days.

So if you decay daily you'll want to pick a lower decay rate than when decaying weekly.

How much decay you choose to have per week is really up to your guild - personally I think 50% per week would be way too much while 1% is too little.

This system needs some decay though as it is quite good as oscillating new members PR around the PR of vets however if two vets have different PRs it takes quite a while for the lower to catch up, say you have

VET A EP: 200,000 GP: 100,000 PR: 2
VET B EP: 150,000 GP: 100,000 PR: 1.5
NEWB C EP: 200 GP: 100 PR: 2

Now let's say the average item costs 100 points, and you earn about 50 per raid. The next item will take C to 200/200 way below A and B, but he can work his way up to the top in 4 raids 400/200. However B needs to attend 1000 raids before being able to catch up with A.

So EP/GP does a good job of allowing new members to be at the top of the food chain for a moment, however without a decent decay vets will have problems getting back to the top.

The later of course is somewhat true for traditional EP-GP systems as well, however when combined with a bidding system you can go from 100,000 pts to 0 with those even without decay and quite fast too.

To me the advantage of this system (EP/GP) is that you a) don't have to put much thought in items costs and effort rewards (a problem with EP-GP)

The downside of EP/GP IMHO is that you don't really have a way of expressing your "need" as you can with a bidding system. Of course you can introduce extra rules like get an item for 10% if nobody else wants it% or start with a 200% cost round, but you can't really take it to the level of a bidding system without defying the purpose of the PR (not to mention the extra time at each "auction" round)

In any case it allows newer members to receive top loot earlier, which may be good or bad depending on your pov.

Comment by evlogimenos, Oct 19, 2007

EPGP is a system you can tailor to your needs. The system itself knows nothing about off-specs, loot for alts or anything of the sort. To cover all those cases you need to adapt it to your guild. For an example of loot rules for our guild you can check out this document:

http://www.aphorism-guild.org/2007/03/loot-system.html

Comment by MrFlexy, Oct 24, 2007

Are we allowed to code it into a website or are their any propriety rights on it?

Comment by evlogimenos, Nov 02, 2007

I am pretty sure you can :-)

Comment by NoSpam4Chris, Nov 03, 2007

Pardon me for being a bit lost on your GP math, but I have been unable to see how you came up with the numbers that you did. For example http://www.wowhead.com/?item=28578. Unless I am mistaken on how I read your formula here is what I came up with, item level = 115, item level requirement is 70. So using either one of those, here is what I came up with. ((115 - 1.3)/ 1.3)^ .04 1 = 305.98

If I use Min. Level requirement I come up with ((70 - 1.3) / 1.3)^ .04 1 = 111.71.

I am sure I missed something along the way, so if anyone could explain what I am missing, I would really appreciate it. Thanks!

Comment by evlogimenos, Nov 08, 2007

Indeed it is hard to come up with the right answers if you look at the current ilvls. All epic loot ilvls were boosted in 2.1 if I remember correctly. These computations are for the old ilvls. I am fixing them now.

Comment by gavin.wilkinson, Nov 08, 2007

Is it ok to make adjustments / alterations to some of the code and then use the altered version of the code?

Comment by evlogimenos, Nov 28, 2007

Yes it is gavin. Please ask those questions in the discussion group (epgp-discuss@googlegroups.com. Wiki comments is not the best place to do so.

Comment by liquid_f...@hotmail.com, Dec 14, 2007

Is it possible to handle people who are online, but not in the raid group?

Comment by evlogimenos, Dec 15, 2007

Yes. Add/Distribute/Recurring EPs work on the current view you have. There are 3 view options: - Raid (those in raid) - Guild (those in guild including offline) - Online (those in guild and online)

Comment by alecmc, Jan 07, 2008

This mod is oh so sexy. It solves the dkp whore problem, the why the fudge nuggets do i have to look up item values every time we kill a boss problem, the attendence problem and is actually kinda fun to use. Roflcopters to anyone who doesn't like it.

Comment by yorchpal, Jan 07, 2008

how guild members see their epgp or pr list?i´d probed in my guild and we don´t see these values.they only see if they are officers...and we don´t want this... there is a form to explain step by step how implement these FANTASTIC addon and dkp system on a guild?

thx

Comment by yorchpal, Jan 07, 2008

members list is not actualizated at moment..when i give them ep or gp...their addon not actualice...

Comment by nsakkas, Jan 30, 2008

The following happened to a raid of my guild. Is this normal? It seems unfair to player A.

Boss Dies. Before awarding 1st boss kill (it was agreed to be a large amount 6000 ep) player A is ahead of player B on RP.

Player A has around 60.000 ep and 900 gp. RP is around 67. Player B (same class) had 11.000 ep and 190 gp. RP therefore is around 57.

Player A was under the impression during the whole raid that he was going to get the loot IF it dropped. (Fact: Player B had quit the guild before, but then decided to rejoin. Since no backup was kept, he effectively RESET his ep,gp and rp)

Before distributing loot, but AFTER killing the boss, the first kill bonus ep is awarded. This is 6.000 ep. I believe EP was so large that it wrecked the formula.

Player A has 60.000+6.000 [10%] = 66.000 ep. with 900 gp, i had now 73 rp (9% more of his previous amount = 67rp).

HOWEVER Player B had 11000+6000 than 50% increase in ep?, with 190 gp, he now has 89 rp!!! (36% more). Which is now higher than Player's A. THus, he gets the item.

Comment by evlogimenos, Jan 31, 2008

Asnwers to comments will be on the google group:

http://groups.google.com/group/epgp-discuss

Comment by splateaux, Feb 27, 2008

nsakkas, I think it was messed up when you awarded the ep THEN you rolled on the loot. I believe the system is designed to away based upon your RP going into a fight, and award ep after the raid... or after the fight (and loot is distributed)


Sign in to add a comment