Evasion Equation - Updated

AIethea - Sanctuary

Many people think evasion / accuracy is broke but I more strongly believe its just not understood in this game. After a bit of testing I finally found the answer though, here is how the game determines your chance to hit.

Evade% = (Target.Evasion-1) / (2* Attacker.Accuracy + (Target.Evasion-1))
Hit % = 1 - Evade%

The Evade% is rounded up to 2 decimal places (remember 0.67 = 67%). The accuracy and evasion rates of monsters can be found from http://www.pwdatabase.com/pwi/. A few mobs were found to have a 100% hit chance when their evasion was 1, hence the offset value displayed in red.

This equation shows that Accuracy in this game is quite a bit more potent that Evasion, hence why some don't think that Evasion works. I hope this helps enlighten anyone who wants to know more about the game.

**Disclaimer** I should note that this is based off of monster hit / evade rates as described by the in game tooltip. Short of a very long, very intensive statistical analysis I have no way of knowing if this is realized in game but I am making the presumption that the tooltip correctly depicts what really goes on.

**Note** This is in contention with the only other person to post an evasion equation 2-3 some years ago. Sadly no one ever seemed to have tested that equation, it was just accepted. Most notably his relies on attacker level as factor with accuracy. There are 2 ways I blew this theory up (feel free to test yoursefl). 1) Tested his equation at the extremes, very high level mobs or esp very low level mobs and disparities become quite prevalent 2) I made a new character and went mob hunting. When I leveled up (w/o adding stats) there was absolutely 0 change in my hit% but there should have been a significant one seen via the old equation.

Fleuri - Sanctuary

So... when fighting someone and their evasion matches your accuracy, you should miss 1/3 of the time?

Asterelle - Sanctuary_1381265973

Fleuri - Sanctuary wrote: »

So... when fighting someone and their evasion matches your accuracy, you should miss 1/3 of the time?

Yah from experience that seems pretty off. BMs and barbs usually have like 5k accuracy to my 5.5k evasion but they hit like 90% of the time....

AIethea - Sanctuary

The only way to figure out for absolute certainty is to do a very long, very intensive statistical analysis with known evasion and accuracy rates. If someone wants to do that be my guest. However, in lue of that, using the info the game provides is the best we have. This does work against monsters and all the info you need is provided. I encourage you to check the formula / tootips. It is possible there is a difference in PvP but that would seem counter intuitive.

The last formula given no one even check, it was just accepted. I did check it and found a better one.

*One additional note about buffs, there was some oddities related to them. Buffs would only be realized once I checked my character sheet and actually saw the number change. If I never opened the character sheet it felt as if the buff was never activated. What is actually going on behind the scenes I have no clue, but from the tooltip standpoint this was peculiar.

Fleuri - Sanctuary

AIethea - Sanctuary wrote: »

This does work against monsters and all the info you need is provided.

Ok, this might be accurate for the displayed numbers. I can double check that.

On the other hand, its entirely possible to miss a monster even when your displayed hit chance is 100%, so I am not quite sure how to interpret your comments.

AIethea - Sanctuary wrote: »

*One additional note about buffs, there was some oddities related to them. Buffs would only be realized once I checked my character sheet and actually saw the number change. If I never opened the character sheet it felt as if the buff was never activated. What is actually going on behind the scenes I have no clue, but from the tooltip standpoint this was peculiar.

Unfortunately, I am totally not sure I understand you. So I will relay my observations about displayed numbers instead:

First, when you get buffed, your character sheet does not change unless you close and re-open it.

Second, when you get buffed, the displayed hit and evade chances for monsters do not change, even if you target new ones, even if they die and respawn.

AIethea - Sanctuary

Fleuri - Sanctuary wrote: »

On the other hand, its entirely possible to miss a monster even when your displayed hit chance is 100%, so I am not quite sure how to interpret your comments.

I have never seen 100% hit chance yet even on the lowest of creatures. From the equation I gave, due to the rounding up, you never will either because even 1 evasion will equate to 1% evade...per the tooltip.

Fleuri - Sanctuary wrote: »

First, when you get buffed, your character sheet does not change unless you close and re-open it.

Second, when you get buffed, the displayed hit and evade chances for monsters do not change, even if you target new ones, even if they die and respawn.

This is exactly what I was talking about but you have not investigated fully. After you check your character sheet to see the number change, then the displayed tooltips on the mobs will change. Until you open your character sheet its as if you never received the buff.

Thus what I mean by "behind the scenes" is that I have no idea when the game actually realizes you are buffed. When you got the buff or when you open your character sheet to see the numbers increase.

StacysMum - Dreamweaver

Chance to dodge at lvl mobs is usually 22 -25% (pure dex) against bosses almost always get hit probability of dodge is a joke.

Evasion is not really an issue or something you should ever rely on.

Why you are even discussing it is perplexing, perhaps you guys like being curious. A bit like learning advanced maths and not applying it to a science or engineering, nice to see you showing an interest but a complete waste of time.

AIethea - Sanctuary

StacysMum - Dreamweaver wrote: »

Chance to dodge at lvl mobs is usually 22 -25% (pure dex) against bosses almost always get hit probability of dodge is a joke.

Evasion is not really an issue or something you should ever rely on.

Why you are even discussing it is perplexing, perhaps you guys like being curious. A bit like learning advanced maths and not applying it to a science or engineering, nice to see you showing an interest but a complete waste of time.

Speaking of people who waste their time...you have already proven your entire comment worthless.

However, because I have been checking this and I also know this communities general attitude towards evasion let me put forth this: Every attack you do relies in part on evasion and accuracy. Its not about gemming or relying on it, though you could find out if that's a good idea or not. Its about the fact that every single target you ever attack will have a chance to evade and reduce your damage. 25% is a lot of damage that you could potentially recover via more accuracy.

Let me ask this, would you take 10 accuracy or 1 dexterity point? Probably a simple answer, but go further, 100 acc vs 1 dex? This is directly applicable, so open up a sheltered little mind and see the entire picture. Always got to take one step at a time.

Vindis - Dreamweaver

Though evasion has its uses, those uses are limited. At end game with +50% accuracy rings dodging is not so guaranteed. Also, magic never misses. That is generally all the argument one needs against evasion vs. something more useful such as physical defense or hp. That is why most people tend to not really care about evasion.

I mean, I too thought evasion amazing back when I had +10% evasion ornaments and like 5.5k evasion buffed. I do still enjoy popping Condor and watching an aps BM chain miss though xD

Fleuri - Sanctuary

AIethea - Sanctuary wrote: »

I have never seen 100% hit chance yet even on the lowest of creatures.

So... you do not remember snowmen?

AIethea - Sanctuary wrote: »

This is exactly what I was talking about but you have not investigated fully. After you check your character sheet to see the number change, then the displayed tooltips on the mobs will change. Until you open your character sheet its as if you never received the buff.

Thus what I mean by "behind the scenes" is that I have no idea when the game actually realizes you are buffed. When you got the buff or when you open your character sheet to see the numbers increase.

I am not quite sure what you are talking about. But I will try some experiments -- it's quite possible that I have overlooked something or that things have changed since I last looked.

But when I am using triple spark for my buff, it has been easy for me to see that character sheet data can be out of sync with my current state.

Asterelle - Sanctuary_1381265973

I don't think anyone is arguing that evasion is useful. The topic is just about the equation to find chance to hit.

Fleuri - Sanctuary

pve displayed chance to evade being hit does currently indeed seem to be:

ceiling( Target.Evasion / (2* Attacker.Accuracy + Target.Evasion))

Also the displayed numbers on the targeting bar update after a few seconds for me now, something which I remember not being the case several years ago.

I wonder how it works in pvp? (And I wonder if different forms of pvp follow the same rules?)

That could not have been how it worked on snowmen though, so I also wonder if some monsters follow different rules, or if the entire game has changed in how these numbers display?

AIethea - Sanctuary

Fleuri - Sanctuary wrote: »

So... you do not remember snowmen?

Nope, I wasn't here for them. For a special mob like that its possible PW gave them 0 evasion. Every other monster (I have found), even level 1 kitties, horses, and chickens, show 99% hit.

Fleuri - Sanctuary wrote: »

I am not quite sure what you are talking about. But I will try some experiments -- it's quite possible that I have overlooked something or that things have changed since I last looked.

Let me put it as simple steps: 1) Look at a mob, note the Eva%. 2) Buff yourself. The mob Eva% has not changed yet. 3) Open your character sheet and see your numbers increase. 4) Look at the mob again, the Eva% of the mob has increased.

Buffing will increase your Eva%, but only after you follow that. So this begs the question, when is the buff actually realized by the game? When / how the game calcs things can be very different from the tooltips (WoW is a prime example...) but it is an indication that something is strange. It potentially could even be the reason behind why some people believe evasion is broken.

AIethea - Sanctuary

As an aside, I wonder what types of comments I would have gotten if I chosen a topic name with accuracy instead of evasion... The two are tied hand in hand.

Asterelle - Sanctuary_1381265973

You can use a jungle belt or eye of observation to check chance to evade in pvp. Maybe I'll check that sometime. I expect the equation to be the same except for having a larger value instead of that '2'.

AIethea - Sanctuary

Fleuri - Sanctuary wrote: »

I wonder how it works in pvp? (And I wonder if different forms of pvp follow the same rules?)

I understand this is of prime importance to most people and I have wondered it myself. Unfortunately this is very hard to test whereas the monster info is rather easy to collect. For now, however, I am sticking to PvE as it should provide incite and allow full dps equations to be built.

If you guys can find oddities or things to look into I will happily check it out and help try to figure out what is going on. I am posting to get feedback from those more experience at this game than I.

Furthermore, I am currently looking into Armor / Magic Resist as well but that will be a separate thread when I come to a conclusion.

Fleuri - Sanctuary

Asterelle - Sanctuary wrote: »

You can use a jungle belt or eye of observation to check chance to evade in pvp. Maybe I'll check that sometime. I expect the equation to be the same except for having a larger value instead of that '2'.

I am not seeing that (http://farm5.static.flickr.com/4137/4851918047_1aa0b7d9be.jpg) unless it would be "Phy. Save"? (But what is "Mag. Save"?)

Anyways, you cannot properly estimate a person's survival chance in archer combat if you do not understand the evasion equation.

Asterelle - Sanctuary_1381265973

Fleuri - Sanctuary wrote: »

I am not seeing that (http://farm5.static.flickr.com/4137/4851918047_1aa0b7d9be.jpg) unless it would be "Phy. Save"? (But what is "Mag. Save"?)

Anyways, you cannot properly estimate a person's survival chance in archer combat if you do not understand the evasion equation.

Click the "My Attributes" drop down. There's more stuff to see including hit chance.

Decus - Dreamweaver

Fleuri - Sanctuary wrote: »

I am not seeing that (http://farm5.static.flickr.com/4137/4851918047_1aa0b7d9be.jpg) unless it would be "Phy. Save"? (But what is "Mag. Save"?)

Anyways, you cannot properly estimate a person's survival chance in archer combat if you do not understand the evasion equation.

Mag. Save is incorrectly labeled, but it is the total amount of -channeling.

AIethea - Sanctuary

Looking into those snowmen (and I managed to find another mob near Heaven's Tear) it does seem to have an offset which isn't noticeable in most normal cases. Here is my addendum which fits those in as well.

Evade% = (Target.Evasion -1) / (2*Attacker.Accuracy + Target.Evasion-1) --round up

For a very specific few data points this equation throws it off by 1% but it made a few others fit better as well. This was only seen when I had very low accuracy (50-) on low evasion mobs. In practical terms, either gives the same results for monsters of a level we would actually care about. All I can say is that the rounding in this game is very strange.

Jaggerjaques - Sanctuary

As far as I've been able to tell, the same rules hold true between both pvp and pve for evasion as much as they do for pdef and mdef. It's just that mobs stats are skewed so far as to make them seem different.

For example, (since my cleric is logged in at the moment), Huggy Hares have an accuracy of 3.7k and an evasion of 70.

Following your formula gives E%=70/(2*25+70)=~58.3%, or a 41% to hit, which matches what the game is showing, so I would assume you are correct, or close enough that the difference wouldn't matter.

ImNotFiveAps - Dreamweaver

Yes, I have 20-25% evasion on most bosses. Yet i get missed maybe 5-10% of the time, if that. Totally accurate.

AIethea - Sanctuary

Glad to get some feedback, even better that its suggesting the equation works . Thanks guys

Fleuri - Sanctuary

ImNotFiveAps - Dreamweaver wrote: »

Yes, I have 20-25% evasion on most bosses. Yet i get missed maybe 5-10% of the time, if that. Totally accurate.

And, yes, I would think there's nothing like accurate numbers. Or maybe this is nothing like accurate numbers?

Anyways, accuracy and evasion only matter for physical attacks, and bosses typically mix both physical and magical attacks. And while a boss might have some kind of "physical magical attacks" that can miss, I think most of them have regular magical attacks that can only be interrupted. (And if anyone wants to figure out how interruption works.... that would also shed light on combat mechanics.)

And, while it's all-too-possible that the displayed numbers have little to do with the implemented mechanics, it's also all-too-possible that the approximations we use to estimate get messed up by how we perceive things.

So... maybe best would be to go find some videos and start counting the physical attacks?

AIethea - Sanctuary

So... maybe best would be to go find some videos and start counting the physical attacks?

That is the analysis that I was talking about before. And feel free. To collaborate the tooltips with the actual game will take some testing. However, the tooltips will be based on the same formula in some form or another so getting that down is a good step forward.

Asterelle - Sanctuary_1381265973

I was able to test check this in game with a jungle belt and the formula matches what the in-game metric says for PVP.

I'm still not sure I believe it as it suggests BMs should be missing on me like 1/3 of the time while it feels more like 1/10.

Sint - Harshlands

Asterelle - Sanctuary wrote: »

I was able to test check this in game with a jungle belt and the formula matches what the in-game metric says for PVP.

I'm still not sure I believe it as it suggests BMs should be missing on me like 1/3 of the time while it feels more like 1/10.

Sometimes it does seem like i get missed a lot, though. On the other hand, i have been killed in condor before, (once by an armageddon crit, once by a demon sparked normal shot crit, several times by sins, sometimes landing several hits in a row.)

Vindis - Dreamweaver

Sint - Harshlands wrote: »

Sometimes it does seem like i get missed a lot, though. On the other hand, i have been killed in condor before, (once by an armageddon crit, once by a demon sparked normal shot crit, several times by sins, sometimes landing several hits in a row.)

They sometimes miss several in a row. I think it is better to look at it like how there is a % chance to crit. 33% chance of crit gives you a pretty constant crit rate, but sometimes you go strings of normal hits without critting. In this scenario each crit would of course represent a miss, but even this seems a bit skewed in my eyes.

AIethea - Sanctuary

Vindis - Dreamweaver wrote: »

They sometimes miss several in a row. I think it is better to look at it like how there is a % chance to crit. 33% chance of crit gives you a pretty constant crit rate, but sometimes you go strings of normal hits without critting. In this scenario each crit would of course represent a miss, but even this seems a bit skewed in my eyes.

This is not a good test at all actually. You really want to test the thing in question directly if possible. Crit's and misses have very different equations and are potentially dependent on each other.

I'm still not sure I believe it as it suggests BMs should be missing on me like 1/3 of the time while it feels more like 1/10.

One problem is who knows what they do on the fly? I have read some strats that suggest changing to the 50% acc rings when you fight an archer. Also, the question about did your buff actually apply itself or do you have to open the character sheet? Lastly, which you might know better than I, are they using skills that can't miss?

Lot of questions still, I'm just scratching the surface I know

Aeroboi - Heavens Tear

Sint - Harshlands wrote: »

Sometimes it does seem like i get missed a lot, though. On the other hand, i have been killed in condor before, (once by an armageddon crit, once by a demon sparked normal shot crit, several times by sins, sometimes landing several hits in a row.)

Sounds to me like
if Crit = True
bypassed Evasion

Idk food for thought

AIethea - Sanctuary

Aeroboi - Heavens Tear wrote: »

Sounds to me like
if Crit = True
bypassed Evasion

Idk food for thought

I think I understand what you are getting at and this would be related to the order the game calculates the attack table. However, what you suggest is unlikely (not saying impossible). The 2 most common models would be a 1 roll and a 2 roll system, and a majority of games have been doing the 1 roll. In short:

1 roll: everything is determined at once based on a single "die throw" (call to random number generator). WoW uses this method. 5% miss, 10% crit leaves you with 85% to regular hit. The benefit is that your crit% is actually 10% and not reduced, also its faster for the server.

2 roll: first die roll is for hit or miss, 5% miss & 95% hit. IF hit then another die roll for crit , 10% crit and 90% reg. This actually reduces your crit rate because of the ones you hit, 10% will be crit, .95*.1 = 9.5% crit in reality.

What you would be suggesting is that the game uses a 2 roll system and asks if it crits first, then asks if it hits. There are tests for this and I have been looking into it, but they just aren't possible for me at my current gear level.