Predicting Crits? - WoWInterface
Thread Tools Display Modes
09-19-06, 12:53 AM   #1
A Murloc Raider
Join Date: Apr 2006
Posts: 5
Predicting Crits?

Just an idea I've been playing around with, and wondering if someone with a bit more knowledge of statistics and addon creation would be able to fulfill it. Or someone who has been around the block a few times and can point me to an addon that does this. :P

Wouldn't it be possible to create an addon that by parsing your combat log could tell you what the odds are that your next attack will crit?

Suppose you have 10% chance to crit, for the sake of easy math. That means out of 10 attacks, you should crit 1 time (barring resists, dodges, parries, etc). If you don't crit in those 10 attacks, odds are in your favor that the next shot will be a crit. These odds would increase every time you don't get a crit. And likewise would decrease every time you do.

Practical application: If I'm 90% sure that my next spell will crit, I'd want to make sure it's a Shadowbolt or Soul Fire and not an Searing Pain. If I only have a 10% chance to crit, maybe I'd want to spam some SP before hitting the Conflag button.

So for the addon I'm thinking have a small Fubar plugin or something that shows what your probability of the next attack being a crit. If the probability is close to 100%, maybe allow for an SCT-esqe message to be sent "Critical Strike Imminent!"

The backend of it would parse the combat log to detect when you cast an ability that can crit, and also whenever that ability actually crits. Possibly even track stats between different spells (since some have higher % chance to crit)

This type of addon would probably be overkill for high-crit classes like rogues, but would work wonders for mages and warlocks. Unsure of how much it would benefit other classes.
  Reply With Quote
09-19-06, 01:06 AM   #2
Premium Member
LaRIC's Avatar
Premium Member
AddOn Author - Click to view addons
Join Date: Jan 2005
Posts: 23
Thats not really how it works

Every spell have a 10% crit chance.. and it doesnt stack. If you do normal hits 100% it still is 10% on next spell.
  Reply With Quote
09-19-06, 06:58 AM   #3
A Cyclonian
katana's Avatar
Join Date: Feb 2006
Posts: 47
Well, of course it's still 10% but that's how statistics work...

It should be possible to compute a crit chance based on previous hits, actually. Like unlikely crit, very likely crit, etc... but not much more. It would be funny though

(and it would annoy rogues ^^)
Calthas, member of Omega on Sargeras.
Holy Devoted Paladin.
  Reply With Quote
09-19-06, 07:23 AM   #4
A Murloc Raider
Join Date: Dec 2005
Posts: 6
In World of Warcraft, hits and misses are calculated before crits, which means that you won't ever have a statistical higher chance to crit on your next attack, since it is reset every time you perform a new attack.

If you have a base 90% chance to hit, 10% chance to miss and 10% chance to crit, you will always have 10% chance to crit on every attack.
This also means that +hit gear can actually raise your chance to crit.
  Reply With Quote
09-19-06, 07:25 AM   #5
A Molten Giant
Beladona's Avatar
AddOn Author - Click to view addons
Join Date: Mar 2005
Posts: 539
Looking at it the wrong way. You can't say "I haven't critted in a while, so I should be getting a crit soon". As someone previously stated, EVERY successful his has a % chance of being a critical. If your critical chance is 10%, then your next hit will be 10% chance of being a critical. And a higher chance to hit doesn't equate to a higher chance to crit. It equates to more hits that COULD crit, but their chance remains the same.

The only real use of something like this in my opinion would be to calculate statistics on how many of your swings were successful, as well as how many of your swings were criticals. I think there are already addons that calculate this, but if you wanted to write one that specifically tracked this data, I am sure it would be useful to someone.
  Reply With Quote
09-19-06, 08:07 AM   #6
A Murloc Raider
Join Date: Dec 2005
Posts: 6
I said that more +hit can raise your chance to crit, but Beladona is right, the chance to crit remains the same on each attack, but since more attacks hit, there should theoretically be more crits.
  Reply With Quote
09-19-06, 08:17 AM   #7
A Murloc Raider
Join Date: Sep 2006
Posts: 5
Maybe you should read up on statistics (http://en.wikipedia.org/wiki/Statistics).
The probability of a crit rises with every noncrit you make. This probability can be calculated and could be used for an Addon that estimates criticals, although it might be a bit of work.

Last edited by projectnova : 09-19-06 at 08:26 AM.
  Reply With Quote
09-19-06, 08:52 AM   #8
A Murloc Raider
Join Date: Dec 2005
Posts: 6
Statistically it goes up, but theoretically the chance to crit remains the same. An addon like that would be pointless in my oppinion, since it's not based on when you got your last crit. With such an addon, you could make a lot of non-crits and the addon would tell that you'd have 100% chance to crit on your next attack.
  Reply With Quote
09-19-06, 09:27 AM   #9
A Murloc Raider
Join Date: Apr 2006
Posts: 5
It doesn't matter that the roll is reset after every cast, because that's how statistics work.

The nice thing about the game is that you can generate pretty large samples pretty quickly. As a caster, I'll cast upwards of 20-30 critable spells per fight. Given your fixed probability of 10%, you can simply base the prediction off the cumlative probability.

For more on dice statistics (which is what i gather we're assuming here):

A pretty table:
Result		Crit% (Probability)  	Cumulative Probability
1 		10% 	 		10%
2  		10% 	 	 	20%
3 	 	10% 	 	 	30%
4 		10%	 	 	40%
5 	 	10%	 	 	50%
6 	 	10%	 	 	60%
7 	 	10%	 	 	70%
8 	 	10%	 	 	80%
9 	 	10%	 	 	90%
10 	 	10%	 	 	100%
So if you cast 100 shadowbolts, you have a 100% chance that 10 of them will crit. This of course is not perfectly accurate, but could give you a ballpark image. Something as simple as "unlikely to crit," "probably crit," and "you're damn unlucky if you don't crit."

With such an addon, you could make a lot of non-crits and the addon would tell that you'd have 100% chance to crit on your next attack.
And thus would be the point of the addon. If you have a LOT of non-crits, the odds are in your favor that you've got at least 1 coming your way (if not a whole long streak of them).

It would be nice if an actual mathematician would hop onboard, and perhaps enlighten us. I'm fairly certain there's more complex models you could use than the one I cited above.

And yes. This addon would probably require a decent bit of work. I myself have never written an addon (or worked with LUA for that matter), and am a mediocre coder at best, thus why I posted the idea rather than writing it myself.

Last edited by diskurzion : 09-19-06 at 09:29 AM.
  Reply With Quote
09-19-06, 10:33 AM   #10
A Cliff Giant
AddOn Author - Click to view addons
Join Date: Aug 2006
Posts: 78
I see what your getting at, but that isn't really the way it works. Probabilities just don't stack. Every instance has a 10% chance. Over the course of a really large sample (hundreds), it should normalize around the 10% chance. But not at the granular level you are looking at trying to accomplish.

Also--the crit % is kinda tricky to derive. Things like attack skill vs. defense skill and whether the mob is facing you or not greatly affect your chances to crit. For example, let's say that you had a 20% crit rate, a 24% chance to miss, 6% chance to get dodged, a 6% chance to get parried, and a 70% to glancing blow (mob is 5 levels above you). In this case...you don't have ANY chance to crit.

On a roll of 100:
24 chance to miss
6 chance to dodge
6 chance to parry
64 to glancing blow
0 to crit
0 to ordinary hit

This is because the sum of 24+6+6+70 is greater than 100, leaving you no chance to crit. Now assume the same mob, but you are the same level. (glancing is 0%, dodge & parry are 5%)

On a roll of 100:
24 chance to miss
5 chance to dodge
5 chance to parry
0 to glancing blow
20 to crit
46 to ordinary hit

If you were facing them from behind, they can't parry. This would increase your hit chance from 46 to 51.
  Reply With Quote

WoWInterface » AddOns, Compilations, Macros » AddOn Search/Requests » Predicting Crits?

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off