Interesting topic from Reddit - "The WR Matchmaking Engine Myth" (for those who are mathematical / statistical inclined)...

[Leo_Apollo11]

Hi all,

 

Interesting topic from Reddit - "The WR Matchmaking Engine Myth" (for those who are mathematical / statistical inclined)...

 

"The WR Matchmaking Engine Myth"

 

 

After another week of this myth popping up, I went ahead and created a completely random win rate generator in Java.

 

http://forum.worldofwarships.com/index.php?/topic/71818-about-that-debunked-wg-mm-patent/page__st__40__pid__1761819#entry1761819

 

The null hypothesis of the argument is that Wargaming has created an algorithm that artificially chokes win rates into the 48-52% win rate range.

However, based on random chance and pool alone, this would not be necessary.

This has the ability to support hundreds of thousands of players and games, and randomly picks victims players to face other players in a completely random set of 50/50 win rates.

 

Note, bucket 50 is 48%<= x < 50%, take previous bucket to current bucket as bracket.

 

Bucket	Players
38	10
40	88
42	533
44	2481
46	7571
48	16210
50	24454
52	22088
54	15698
56	7660
58	2527
60	588
62	82

 

Repeated testings show, as expected, players falling into 48-52 buckets naturally. Why? Because win rate is often outside any single player's control, and because win rate is harder to change the more you play. For a player with 500 games and a 50% win rate to get to a 60% win rate, the player must win an unprecedented 125 games in a row. The natural gravitation towards 50% win rate is expected simply because of how much outside the own player's control a game's outcome can be, regardless of how good a player is. We certainly see that an average player in a coin toss game can get to the 60% WR range even when they are perfectly equivalent to everyone else due to simple randomness.

Run your own tests on smaller samples here: http://ideone.com/6VhL3Y

 

Edit: I created a bias simulator as well for the people who want to see what happens when an underlying skill is taken into random matchmaking.

 

https://ideone.com/dr99xq

 

Skill is on a scale of 0 to 1.0, with 1.0 being best and 0 being worst. Your skill is added up with your team to determine the odds. Two teams of 6 skill apiece have a 50% chance of winning and losing. A ratio of skill capabilities between each team is used to determine other win ratios, with the higher skill team being favored to win in the exact ratio, so a 3 skill vs 1 skill has a 75% chance of winning. Even with an average skill deviation of approximately 1 whole skill level in difference, the favored teams only won 55% of the time.

 

 

 

Leo "Apollo11"

[Sake78]

There is nothing you, or anyone else can say, or do, to convince some players, just as nobody can convince the loonies that still think the Lunar landing was filmed in studio.

 

Otherwise, that is the perfect explanation for "Why should WG complicate its life when random does it naturally, anyway?". But, to some, this will never be enough.

[LilJumpa]

Didn't read it all (the thread). What did he do?

 

Write the gaussian distribution in JAVA and proved it (again)?

[Sake78]

Pretty much using actual numbers in a scenario, to prove that the target is achieved naturally, hence no need for any fancy schmancy "rigging of the matchmaker".

[piritskenyer]

Yeah, yeah, we all know the MM is rigged so that everyone should gravitate towards a 50%. If that was the case there would be no 46% players and no 60-65% players.

[snipershot]

Well skill obviously is the one factor that can beat the mm, especially a really good division.

 

But if youre a solo casual newby who never plays the game hardcore to the point of excellence(like me), you probably will feel like the victim in a lot of games, because you have much less impact.

[Risalan]

"After another week of this myth popping up, I went ahead and created a completely random win rate generator in Java."

 

Impossible, no computer can generate random mumbers (I don't know if quantum computers can).

 

And another fact is that wining is not a random experiment,it's not coin toss. Depends on which ships and which captains, good ship in good hands can make the diference, not to mention good division. That's why RNG took place to level the game. I know pleople in WOT, in my clan, how play a tank until get the X2 of the day, I assume that happens in WOWs, I don't, two in a row lost and I don't play that ship until next day.

[Risalan]

Yeah, yeah, we all know the MM is rigged so that everyone should gravitate towards a 50%. If that was the case there would be no 46% players and no 60-65% players.

 

It could be. but beating MM it's not easy. You can play division with other 2 players (3/12=25%) and make the diference in a battle, or play the ships you're good with and no others. My best ship Umikaze(II) IJN DD 79% win 48 battles, worst Isokaze (IV) IJN DD 34% win 38 battles. But in the long term 50%, Tirpitz (VIII) BB KM Premium 50% win 337 battles, New Orleans (VIII) CA USN 45% win 130 battles, Minekaze (V) DD IJN 55% 124 battles. Why I have 63% with Kamikaze-R when it's worst than minekaze, because only 16 battles with she.

 

The lesson it's you can fight MM and RNG but you can beat them.

[Sake78]

"After another week of this myth popping up, I went ahead and created a completely random win rate generator in Java."

 

Impossible, no computer can generate random mumbers (I don't know if quantum computers can).

 

And another fact is that wining is not a random experiment,it's not coin toss. Depends on which ships and which captains, good ship in good hands can make the diference, not to mention good division. That's why RNG took place to level the game. I know pleople in WOT, in my clan, how play a tank until get the X2 of the day, I assume that happens in WOWs, I don't, two in a row lost and I don't play that ship until next day.

 

Don`t be silly: http://www.pas.rochester.edu/~stte/phy104-F00/notes-2.html . Of course mathematics can make a random number generator. It can even predict it.

 

And it IS a coin toss, because you have 2 teams. The players can be considered "weights", or "weighted flip", but it is also explained there, that ONE player out of 12, or one weight out of 12 cannot influence the coin toss to such an extent as to influence the outcome of a random unweighted toss.

 

https://www.fourmilab.ch/rpkp/experiments/statistics.html <-- coin toss experiment and distribution, very nicely explained - all it`s missing are pop-up pictures.

 

It is also funny how the first nay-sayer resorts to fantasy arguments, like "we cannot make a random number generator" and adds even more conspiracy theory, by adding one more "bias mechanic", such as the RNG ( brownie points if you can spell the letters for me and what they mean - and WG is unlikely to have quantum computers, or an employee called Worf, with a big knife ). Just proves my previous point, I guess - alternate reality at its finest.

[Black0rchid]

Well all I can say is that if a model can predict something then that something is no longer random and is as predicted... (you can quote me on that)

 

Eitherway, I find the over simplistic model used by the reddit guy is created to prove his point. Matchmaking can and will influence the end game periode. You can give me all the statistics you want saying it won't but real life says otherwise. In the same way skill of players can also influence the match, and the randomness of accuracy, fire starting chance, detonation chance etc.....

 

So .... if you are a real science guy....take that into account, pour it all in mix it and tell me is it that hard to bypass player skill? Do all these factors also put you in 50% win chance? 

 

I know that the 60% winrates are flukes of the normal deviation to the average...as are the 40%....

 

But in the end everyone needs to belive something outside their mind......and in the internet there is only one god....rnjesus!

[Sake78]

Well all I can say is that if a model can predict something then that something is no longer random and is as predicted... (you can quote me on that)

 

It can predict the chance of something happening, yes, like a string of 4 heads, or 6 tails in a row, or in this case, what is the probability of landing 10 losses in a row. You see, mathematics isn`t a mumbo-jumbo of "I don`t believe you, cos I don`t wanna", or "Ya, but, like, if I can calculate probability, then it`s like... not random". 

 

As for the rest, it IS taken into account, as it DOES NOT exclude any win rate higher or lower than 50%, but you would have known that if you would have known anything about statistics past "Ya, but...".

 

Anyway... contrary to what people believe, mathematics is not up for debate - not without a degree, anyway, and I seriously doubt anyone here is capable of doing it, so we`ll just take it "as is". This is the equivalent of those Stone Age present day people that still ignore the doctor`s advices, which come from a lil` thing called school and various specialisations and qualifications via exams, and go to the village elder for his World Famous Prune Juice That Cures Everything for only 4.99 a bottle.

[XTHD]

Didn't read it all (the thread). What did he do?

 

Write the gaussian distribution in JAVA and proved it (again)?

 

Pretty much. Nothing to see here really. An army of clones fighting against each other in a random matchmaking will have their win rates normally distributed. A truly groundbreaking discovery. And highly irrelevant to the actual topic.

[Risalan]

 

Don`t be silly: http://www.pas.rochester.edu/~stte/phy104-F00/notes-2.html . Of course mathematics can make a random number generator. It can even predict it.

 

 

Maths yes a computer no, and as said he used Java. The most dificult problem with computers it's random generators, you can simulate but computers works with algorithms. 

 

I'm a referee my last 8 toss 7 tails 1 head and all we know that the chance it's 50%, real life can be also tricky. 

[Risalan]

 

It is also funny how the first nay-sayer resorts to fantasy arguments, like "we cannot make a random number generator" and adds even more conspiracy theory, by adding one more "bias mechanic", such as the RNG ( brownie points if you can spell the letters for me and what they mean - and WG is unlikely to have quantum computers, or an employee called Worf, with a big knife ). Just proves my previous point, I guess - alternate reality at its finest.

RNG Random Number Generator, that means in every shot WG try to know the probality of impact and how much damage it's made, as said it's no real random so depend of the program some hits with more damage are more likely than in real life. Or explain me how can get a citadel hit in my NC with 45% armor angle, mathematically imposible, but WG make it posible.

[Black0rchid]

Hmmm so bitter when it comes to maths, I can hardly recognize you sake78, looks like I found your sweet spot

 

I had in fact 3 semesters of statistics back in University (yeah a while back), and I do believe that statistics and mathematics are quite different. Mathematics is an exact science hence a SCIENCE, statistics plays on odds and probability's and variables, so yeah it's up for debate. The fact that you can predict something will happen in statistics does not mean it will happen...it means it has a given amount of chance that it will happen (and here is were we introduce the IF's and BUT's) In a game like this one the variables cannot be reduced into win rate (an average) and that is what i tried to say in the previous post. I consider Win rate just that... average of the games played. That is also the reason I don't like the XVM mod from world of tanks....but that has been explored in other topics.

 

So back to my original post 40% and 60% .....the both of us go for lunch and we buy 2 chickens, we both eat them all, I ate 1.5 and you 0.5 (maths) yet on average we ate 1 chicken each (statistics).... 

 

I do believe MM, RNG, Player Skill etc do have an influence in game, as do environmental variables that are not controlled directly by us and exert an influence on the way we play. Now the question and the point I was trying to make was....is it possible with a simplistic model as the original poster in reddit did to come to a conclusion? Yes he can come to a conclusion, but statistically speaking the odds of him being wrong is 90%. Why ? because he didn't to take into account all the variables that can influence the odds, he focused on just one. Oh but he can take them into account by calculating a standard deviation.......yeah if he does that he will end up with such a deviation that the end odds will be so screwed up he won't be able to draw any conclusion.

 

And that is why it's much easier for players to believe in RNJesus influencing the game ....than in fact blaming themselves. Notice ....when it isn't RNG it's the teams fault !

 

 

 

 

 

 

 

 

[piritskenyer]

[Sake78]

snip

 

Here is what I think and what is proven in that OP, as simple as some say it is: our beloved 2 teams are just as random as one coin toss sitting on the edge. The 12 players in each time act as a weight that will try and move the pretty high center of gravity of said coin to one side or the other. Most of the time they cancel eachother out, making it a perfect random coin toss, with all that entails. SOMETIMES, there is a player, or more, as a division, or coordinated divisions pressing battle at the same time, that they add just a tad more weight on one side of the coin, making it fall on one side more - emphasize on more, not always.

 

All of the above in the OP proves that theory using numbers, just as the actual mathematics proves it regardless.

 

So, the question is still valid - Why would WG spend such an effort into rigging something that is achieved by itself?

 

http://forum.worldofwarships.eu/index.php?/topic/28425-is-mm-going-to-mess-with-good-players-again/page__st__280#topmost <-- this was a pretty heated argument, that posed a question, past the actual official answer:

 

So here's a challenge:

You have 3 good players.

You have 9 bad players

You have 12 average players.

 

You can set whoever you like as top or bottom tier, but please make a 12 vs 12 game where the good players lose and the bad players win. (As the supposed point is to bring everyone closer to 50%)

 

Also, sorry if I come as abrupt, but I have absolutely no patience for people that believe in conspiracy theories

[t3h3th32]

So, this's supposed to prove what exactly? That MM is 100% random and 48% - 52% winrate majority is created only as a natural side-effect?

 

Cheers,

~t3h'Pâr4d0x

[XTHD]

So, this's supposed to prove what exactly? That MM is 100% random and 48% - 52% winrate majority is created only as a natural side-effect?

 

Cheers,

~t3h'Pâr4d0x

 

It displays what I described above, which isn't anything previously unknown, or even highly relevant to the topic he was trying to apply it on. You'd usually do something like this as a computer lab in an introductory statistics course.

[FaceFisted]

So much /facepalm in this topic. I can't read what sheep is writing again.

 

You think that MM is not moderated? Guess again! Why is it moderated? Because - money.

 

Most of the players are terrible at this game and they don't want to spend money if they have stats to prove how terrible they are. Minority of players are good, but in WG perspective - who cares about them since they are minority. SO, in order for bad players begin and continue to spend money, they are put in teams where they can win, while those who can make a difference are put with teamkillers, bots, afk players etc.

 

Like here for example

 

 

 

In the end of the match, those terribad player will have a bit higher WR, while those good ones will have lowered WR, because they have >60% WR and MM is starting their rigged losing streak that will place them in such teams for next 10 days. If those good players dare to play good again and have a day or two of fresh air when it comes to teams, MM will AGAIN put them in terrible teams. Until they are evened out with bots when it comes to WR or they just get fed up with this BS and quit a game. 

[LilJumpa]

I think you just made my ignore list 

 

[gr0pah]

So much /facepalm in this topic. I can't read what sheep is writing again.

 

You think that MM is not moderated? Guess again! Why is it moderated? Because - money.

 

Most of the players are terrible at this game and they don't want to spend money if they have stats to prove how terrible they are. Minority of players are good, but in WG perspective - who cares about them since they are minority. SO, in order for bad players begin and continue to spend money, they are put in teams where they can win, while those who can make a difference are put with teamkillers, bots, afk players etc.

 

Like here for example

 

 

 

In the end of the match, those terribad player will have a bit higher WR, while those good ones will have lowered WR, because they have >60% WR and MM is starting their rigged losing streak that will place them in such teams for next 10 days. If those good players dare to play good again and have a day or two of fresh air when it comes to teams, MM will AGAIN put them in terrible teams. Until they are evened out with bots when it comes to WR or they just get fed up with this BS and quit a game. 

 

So how did this happen?

http://warships.today/player/503973851/eu/papedipupi

[Black0rchid]

Matchmaking is crap in this game. Although I have seen some improvements since I started playing, it is far from ideal. Now to go as far as to say that WG intentionally does that is a bit of a stretch. I would be much more inclined to say that the RNG that actually influences the game is related to shell dispersion (there was a previous thread on the subject) and hit ratios, and that is much easier to control. Why? Because for the matchmaking you can have a team with great players that actually know what they are doing with the given ships they are sailing even if they are under tiered and that will dominate the other team. However if you cap the amount of times they will do significant damage (notice I did not say hit ) to the enemy.... well no mater how good you are the odds will not be in you're favor.

 

But again....these are theories and suppositions, not facts. Facts are that players tend to fall into the 50% WR ....why ? No idea, but this is the first game I have played in witch the best are only 10% to 20% better than the rest.

 

This is a normal distribution curve in statistics..........and it applys here like a glove as to the win rate of players

 

[Sake78]

But again....these are theories and suppositions, not facts. Facts are that players tend to fall into the 50% WR ....why ? No idea, but this is the first game I have played in witch the best are only 10% to 20% better than the rest.

 

Because the vast playerbase is just average, and, as such, the most players online at any given time (with the exceptions of sealclubbing divisions in late / early hours) are just average, making any result unpredictable, as there isn`t any clear better team. And this is true for any game that involves PvP, where, the further you are from the absolute mediocrity, the fewer players you will find. Also, 10 to 20% better than the rest is a big deal here, considering the effort it takes to swing the odds with 12 enemies, or only as one out of 12, or even as a division, which amounts to only 25% of "skill bias" in a team. The number to go from 50% WR to 60% WR over lets say 5000 games is astronomical, from the point of view of consecutive won games needed.

 

http://worldofwarships.eu/en/community/accounts/529265619-Flamu/!/pvp/overview/ <-- this guy is "only" 10% better than your average Joe. Does it look like he is only 10% from his team and other statistics? 

 

So, this's supposed to prove what exactly? That MM is 100% random and 48% - 52% winrate majority is created only as a natural side-effect?

 

Cheers,

~t3h'Pâr4d0x

 

The vast population are just average players and teams are just random. It is a natural effect, not side-effect, that a mediocre player will never influence his team. The better the player is, or the more "skew" one puts in the game, ala divisions, the more he can influence the outcome of a battle, up to a theoretical 75% WR, which might be a result of heavy divisioning and better ships played.

 

But yes, is that simple - it is perfectly natural, because that is how all games are - vastly populated by just average players.

[Lieut_Gruber]

One thing the MM could do to influence my WR, is the tier it puts me in. If me in my T6 ends up in a T8 battle, my skills have less influence than me in a T8 ship in a T6 battle. But what has the biggest impact is division play. I was at 60% after playing mostly divisions, but after my mates got bored and left the game, i slowly start to descend. I actualy think the MM does try to balance divisions with higher tier oponents.