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On March 25 2014 21:44 obesechicken13 wrote:Show nested quote +On March 25 2014 21:28 MarcoBrei wrote:On March 25 2014 21:14 obesechicken13 wrote:I think the actual distributions may be slightly different for arena runs. http://www.arenamastery.com/sitewide.phpArena mastery shows some great players so their sitewide stats sit around 4 wins average, but they have a lot of 12s compared to your simulation. This could be because some players legitimately have a greater than 50% chance of winning a certain match. The average # of wins in a run should be around 3 though. 2.9-3.1 ish. Arena mastery does not have all information, right? Just the ones people submit, if I'm correct. If so, several results, specially the bad ones, may not be present, which ruins the metric. About "50% of chance", let me clarify that in my simulation we do not have this rule. Players win game based on their skills, and people have different skills simulating a normal distribution over the population. I agree with the first point. How did you assign skill levels to players? did you give each a point rating and use that to determine their probability of winning? What did the distribution of skill levels look like? Did you use something like Elo distributions for chess or lol?
Skill is a number. Players have skills varying from 0 to 10. As expected in a normal distribution, there are a lot more people with skill around 5 than people with skill around 0 or 10, and that's done gradually. I also know the distribution I made is not perfect real, but I think it is enough to use in this test. When a player faces another player, basically the one with better skill wins. But I introduced some RNG to allow a worse skilled player to have a chance to win. Lets say player X with skill equals to 6.5 faces a player Y with 7.0. The considered skill in the match is something like this: X: a random number from 5.85 to 7.15 Y: a random number from 6.3 to 7.7 The player Y has more chance to win, but player X still have his chance. If the players have too discrepant skills then the victory of the best player is certain.
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Canada7170 Posts
On March 26 2014 02:18 MarcoBrei wrote:Show nested quote +On March 25 2014 21:44 obesechicken13 wrote:On March 25 2014 21:28 MarcoBrei wrote:On March 25 2014 21:14 obesechicken13 wrote:I think the actual distributions may be slightly different for arena runs. http://www.arenamastery.com/sitewide.phpArena mastery shows some great players so their sitewide stats sit around 4 wins average, but they have a lot of 12s compared to your simulation. This could be because some players legitimately have a greater than 50% chance of winning a certain match. The average # of wins in a run should be around 3 though. 2.9-3.1 ish. Arena mastery does not have all information, right? Just the ones people submit, if I'm correct. If so, several results, specially the bad ones, may not be present, which ruins the metric. About "50% of chance", let me clarify that in my simulation we do not have this rule. Players win game based on their skills, and people have different skills simulating a normal distribution over the population. I agree with the first point. How did you assign skill levels to players? did you give each a point rating and use that to determine their probability of winning? What did the distribution of skill levels look like? Did you use something like Elo distributions for chess or lol? Skill is a number. Players have skills varying from 0 to 10. As expected in a normal distribution, there are a lot more people with skill around 5 than people with skill around 0 or 10, and that's done gradually. I also know the distribution I made is not perfect real, but I think it is enough to use in this test. When a player faces another player, basically the one with better skill wins. But I introduced some RNG to allow a worse skilled player to have a chance to win. Lets say player X with skill equals to 6.5 faces a player Y with 7.0. The considered skill in the match is something like this: X: a random number from 5.85 to 7.15 Y: a random number from 6.3 to 7.7 The player Y has more chance to win, but player X still have his chance. If the players have too discrepant skills then the victory of the best player is certain. I have issues with this methodology, but you've inspired me to construct my own simulation. 
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On March 26 2014 02:33 mikeymoo wrote:Show nested quote +On March 26 2014 02:18 MarcoBrei wrote:On March 25 2014 21:44 obesechicken13 wrote:On March 25 2014 21:28 MarcoBrei wrote:On March 25 2014 21:14 obesechicken13 wrote:I think the actual distributions may be slightly different for arena runs. http://www.arenamastery.com/sitewide.phpArena mastery shows some great players so their sitewide stats sit around 4 wins average, but they have a lot of 12s compared to your simulation. This could be because some players legitimately have a greater than 50% chance of winning a certain match. The average # of wins in a run should be around 3 though. 2.9-3.1 ish. Arena mastery does not have all information, right? Just the ones people submit, if I'm correct. If so, several results, specially the bad ones, may not be present, which ruins the metric. About "50% of chance", let me clarify that in my simulation we do not have this rule. Players win game based on their skills, and people have different skills simulating a normal distribution over the population. I agree with the first point. How did you assign skill levels to players? did you give each a point rating and use that to determine their probability of winning? What did the distribution of skill levels look like? Did you use something like Elo distributions for chess or lol? Skill is a number. Players have skills varying from 0 to 10. As expected in a normal distribution, there are a lot more people with skill around 5 than people with skill around 0 or 10, and that's done gradually. I also know the distribution I made is not perfect real, but I think it is enough to use in this test. When a player faces another player, basically the one with better skill wins. But I introduced some RNG to allow a worse skilled player to have a chance to win. Lets say player X with skill equals to 6.5 faces a player Y with 7.0. The considered skill in the match is something like this: X: a random number from 5.85 to 7.15 Y: a random number from 6.3 to 7.7 The player Y has more chance to win, but player X still have his chance. If the players have too discrepant skills then the victory of the best player is certain. I have issues with this methodology, but you've inspired me to construct my own simulation. 
Even if my simulation have some flaws, it inspired someone to try some similar work, so it's a good thing! 
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Thank you. You did something I was considering doing, but was too busy. Basically, I suspected the way certain people (who are good at arena) advertise arena may be over the top a bit. Like poker, and essentially most things that depend on experience, this looked a bit like a pyramid scheme. In which they always claim your best value is in a arena, but if we actually take *all* players in arena and just average out their performance, it would turn out that the "bank" (in our case Blizzard) wins more from us, compared to what "we" (that is the whole average of all players) can just win from constructed. So yeah, the arguments still stand, you could keep playing arena (do the pyramid work) until you get good enough to actually pull better gold from it than you would from constructed. Individually - for those that are good or become good - there's great value in arena, the best value. But as a whole, I suspected the entirety of players do not benefit from it, and your results pretty much confirm it. Of course, the difference is very small, and arena is fun, so it's still okay. EDIT: also, of course, there's a 100 gold limit in constructed which if you grind a lot will be an issue.
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Original post updated:
UPDATE - from relevant inputs:
Gerenal questions about the program: + Show Spoiler +"gerenal questions about the program" How did you make the normal distribuiton of skill? How did you make the matchmaking? How did you decide the winner? How did you make the RNG?
I really don't want to discuss details of the program, just because it's tiresome. There is no much famous algorithm behind this program, I made myself every step of it. Some overview: Skill is a number, the greater, the better. Normal distribution: More players have skills like 5, less players have skill like 10 or zero. It increases and decreases gradually. Matchmaking: I don't know how blizzard does, I just pick a random player and try to find another with the same (or as close as possible) "win balance" (win - loss). So a player with 7-0 will play against a 9-2 instead a 9-0. The winner is decided by comparing the skills. But I introduced some RNG to allow a worse skilled player to have a chance to win. Lets say player X with skill equals to 6.5 faces a player Y with 7.0. The considered skill in the match is something like this: X: a random number from 5.85 to 7.15 Y: a random number from 6.3 to 7.7 The player Y has more chance to win, but player X still have his chance. If the players have too discrepant skills then the victory of the best player is certain. Important update: I just made some more simulations varying the amount of RNG and find out that it does not make that big of a difference. Also, I mixed the normal distribution of skill and still get similar results. On the other hand matchmaking is much more relevant and affects a lot the results.
Comparing this result with... + Show Spoiler +I don't think arenamastery has all necessary data, just the ones people submit. If so, several results, specially the bad ones, may not be present, which ruins the metric. The only way to confirm the results would be comparing with real data from Blizzard, and I would love to do that. I know this simulation is not perfect, but I think it can give us a clue about what happens. Some methods should be done differently, but so far I think nothing is "wrong enough" to invalidate the results. What I'm saying is that we can't learn here that exactly 77.96% of the players reach no more than 4 victories, but we can imagine this number is not 30% neither 90%.
Some aspects the simulation does not consider: + Show Spoiler +On March 25 2014 17:23 RenSC2 wrote: One further consideration is that each "player" in the simulation is not actually an individual, but instead a single run of the arena. A person who averages 3 wins or less in a run will likely only be able to play in the arena once every couple days. A person in that 4-6 range will be able to run arena about 1-2 times per day. People who average 7+ get to run the arena as much as they want. Some of the really top notch arena people are full time streamers/players and so do a very large number of runs every day and account for many runs in the 7+ club.
So the actual % of people who will average 7+ is less than what the simulation will tell you because a larger portion of those runs are being filled by the same people. Meanwhile, the less than 3 club will actually be a much larger % of people since those people don't get to make nearly as many runs as even the 4-6 people.
Essentially, averaging 5 wins or more per run actually puts you in better standing than the top 22% that the initial post calculated.
The only caveat is that real $ infusions are probably highest in the less than 3 club and those people could be balancing things out a bit.
Still, we live on a forum where being "only" in Masters in Starcraft makes you a "bad" player. Masters was initially supposed to be the top 2% of the active playerbase. We're a very elitist community.
Other simulation + Show Spoiler +This is simulating the ladder, it's interesting, but I wanted to try Arena which I think is more interesting
Inspiration + Show Spoiler +On March 26 2014 02:33 mikeymoo wrote:I have issues with this methodology, but you've inspired me to construct my own simulation.  On March 25 2014 11:02 Came Norrection wrote: You just made me want to write my own simulation.
Feel free to try your own tests! When blizzard reveals the real numbers we may see who was more accurate 
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This is a well done analysis. Thank you very much for the effort you have put into this, and for sharing the results with us. I have two comments:
1. Please share the computer code you have used for your simulation. This allows us to more deeply understand what you have done.
2. My guess would be that the implied distribution of players across "number-of-win-categories" (0-3,1-3, and so on) dependens to some degree on the assumed probability distribution for "skill". If you have time, I would be interested in seeing the implied distribution for different assumptions on "skill".
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I was inspired by MarcoBrei's work to write my own simulation. There are some differences between those numbers and mine, but they mostly agree:
- 50% of players end up with 2 wins or less. Only 50% have 3+ wins. (Compare to MarcoBrei's 51.57%/48.43%)
- 65.6% end up with 3 wins or less. Only 35.4% have 4+ wins. (MarcoBrei: 66.91%/33.09%)
- Only about 9% have 7+ wins. (MarcoBrei: 9.01%)
- I did not see significantly different results when match outcomes were determined randomly (50/50 chance to win) vs. determined by skill (higher skilled player always wins).
Data: + Show Spoiler +0-3: 12.500% (12.500% 0-0 wins, 87.500% 1+ wins)) 1-3: 18.750% (31.250% 0-1 wins, 68.750% 2+ wins)) 2-3: 18.750% (50.001% 0-2 wins, 49.999% 3+ wins)) 3-3: 15.625% (65.626% 0-3 wins, 34.374% 4+ wins)) 4-3: 11.719% (77.345% 0-4 wins, 22.655% 5+ wins)) 5-3: 8.203% (85.548% 0-5 wins, 14.452% 6+ wins)) 6-3: 5.469% (91.017% 0-6 wins, 8.983% 7+ wins)) 7-3: 3.516% (94.532% 0-7 wins, 5.468% 8+ wins)) 8-3: 2.197% (96.729% 0-8 wins, 3.271% 9+ wins)) 9-3: 1.343% (98.072% 0-9 wins, 1.928% 10+ wins)) 10-3: 0.806% (98.877% 0-10 wins, 1.123% 11+ wins)) 11-3: 0.476% (99.353% 0-11 wins, 0.647% 12+ wins)) 12-2: 0.476% 12-2, (99.829% less or equal, 0.171% higher)) 12-1: 0.146% 12-1, (99.976% less or equal, 0.024% higher)) 12-0: 0.024% 12-0, (100.000% less or equal, 0.000% higher))
I believe that my simulation differs in that it uses "perfect matchmaking", without any randomness. For example, an 0-2 player will only ever get matched with another 0-2 player, and the result is that there will always be one of those players ending with an 0-3 run.
I've also played around with different player distributions. For example, under the assumption that more higher-skilled players tend to play Arena (because they find it profitable), that lower-skilled players avoid Arena (more efficient to buy packs), and that there's a crop of new, unskilled players playing their free Arena run. The other distribution types I've tried are Normal (bell curve) and equal. So far, these different distributions don't seem to affect the results much in the long run, in a situation where there is perfect matchmaking.
I agree that the matchmaking algorithm is the most important factor in the distribution of arena win rates.
I will make my computer source code available for people to view and run. I'm currently looking into where best to host the code. Thanks, MarcoBrei for inspiring this effort.
Edit: added: The source code and sample run output.
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Interesting simulation.
I do agree with the analysis that the people who can consistently hit 7+ wins will represent a significantly lower percentage of players though. There is a small subset of users that can average 7+, and that means that for every arena run, they take out 2 1/3 players on average, not to mention the fact that they'll get enough money to go right back and do it again.
While John Pub might win 2-3 games most of the time, they won't get enough gold for more than one arena run a day, in comparison to a higher level player who might do 5 or more, averaging more than double the wins.
I also think getting to 12 wins requires an element of luck in addition to skill. Some good decks that could hit 6-7 most of the time occasionally run into 3 very strong decks, and then sometimes an average deck will hit 12. Unless you've drafted something like 3 consecrate 5 truesilver triple aldor tirion pally, or 4 frostbolt 3 manawyrm 5 fireball 3 flamestrike double poly pyro mage with solid supporting cards(which is an element of luck as well), you can predict a good range for a deck, but never be certain.
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I updated the simulation program: source code and sample output.
We already know what distribution of results to expect overall. However, what people are probably more interested in is the question, what Arena result can an individual player expect to receive based on their skill level? The simulation program now tries to tally this information. There are 14 player skill levels, from 1 (worst) to 14 (best).
Average Skill Level per Result: + Show Spoiler +0-3: n=125000, average level=4.1 1-3: n=187500, average level=6.5 2-3: n=187500, average level=7.6 3-3: n=156250, average level=8.2 4-3: n=117187, average level=8.9 5-3: n=82031, average level=9.7 6-3: n=54687, average level=10.6 7-3: n=35155, average level=11.3 8-3: n=21971, average level=11.8 9-3: n=13426, average level=12.3 10-3: n=8055, average level=12.6 11-3: n=4759, average level=12.9 12-2: n=4759, average level=13.2 12-1: n=1464, average level=13.4 12-0: n=244, average level=13.5 Average Result per Skill Level (whale2 distribution): Level 1: n=70044, average wins=0.3 Level 2: n=4995, average wins=0.4 Level 3: n=9944, average wins=0.5 Level 4: n=15038, average wins=0.8 Level 5: n=19942, average wins=1.2 Level 6: n=89749, average wins=1.6 Level 7: n=200544, average wins=2.1 Level 8: n=199102, average wins=2.5 Level 9: n=110207, average wins=3.2 Level 10: n=99744, average wins=4.0 Level 11: n=80368, average wins=5.1 Level 12: n=50238, average wins=6.2 Level 13: n=30051, average wins=7.3 Level 14: n=20022, average wins=8.6
The above is using a non-standard distribution of players that I've named "whale2". It assumes that Arena has more higher-skilled players than the normal population, with low-skilled players avoiding Arena but with a number of new, inexperienced players trying out their free run.
Player skill level distribution (whale2): L1: 7.00%, L2: 0.50%, L3: 0.99%, L4: 1.50%, L5: 1.99%, L6: 8.97%, L7: 20.05%, L8: 19.91%, L9: 11.02%, L10: 9.97%, L11: 8.04%, L12: 5.02%, L13: 3.01%, L14: 2.00%,
With a normal distribution of players, the results instead look like: + Show Spoiler +Average Result per Skill Level (normal distribution): Level 1: n=1016, average wins=0.2 Level 2: n=5053, average wins=0.3 Level 3: n=16623, average wins=0.5 Level 4: n=43939, average wins=0.8 Level 5: n=91984, average wins=1.3 Level 6: n=150681, average wins=1.8 Level 7: n=191184, average wins=2.4 Level 8: n=190992, average wins=3.1 Level 9: n=150072, average wins=3.9 Level 10: n=91477, average wins=5.0 Level 11: n=44057, average wins=6.4 Level 12: n=16932, average wins=7.9 Level 13: n=4965, average wins=9.5 Level 14: n=1013, average wins=10.8
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On May 09 2014 12:53 BenJamesBen wrote:I was inspired by MarcoBrei's work to write my own simulation. There are some differences between those numbers and mine, but they mostly agree: - 50% of players end up with 2 wins or less. Only 50% have 3+ wins. (Compare to MarcoBrei's 51.57%/48.43%)
- 65.6% end up with 3 wins or less. Only 35.4% have 4+ wins. (MarcoBrei: 66.91%/33.09%)
- Only about 9% have 7+ wins. (MarcoBrei: 9.01%)
- I did not see significantly different results when match outcomes were determined randomly (50/50 chance to win) vs. determined by skill (higher skilled player always wins).
Data: + Show Spoiler +0-3: 12.500% (12.500% 0-0 wins, 87.500% 1+ wins)) 1-3: 18.750% (31.250% 0-1 wins, 68.750% 2+ wins)) 2-3: 18.750% (50.001% 0-2 wins, 49.999% 3+ wins)) 3-3: 15.625% (65.626% 0-3 wins, 34.374% 4+ wins)) 4-3: 11.719% (77.345% 0-4 wins, 22.655% 5+ wins)) 5-3: 8.203% (85.548% 0-5 wins, 14.452% 6+ wins)) 6-3: 5.469% (91.017% 0-6 wins, 8.983% 7+ wins)) 7-3: 3.516% (94.532% 0-7 wins, 5.468% 8+ wins)) 8-3: 2.197% (96.729% 0-8 wins, 3.271% 9+ wins)) 9-3: 1.343% (98.072% 0-9 wins, 1.928% 10+ wins)) 10-3: 0.806% (98.877% 0-10 wins, 1.123% 11+ wins)) 11-3: 0.476% (99.353% 0-11 wins, 0.647% 12+ wins)) 12-2: 0.476% 12-2, (99.829% less or equal, 0.171% higher)) 12-1: 0.146% 12-1, (99.976% less or equal, 0.024% higher)) 12-0: 0.024% 12-0, (100.000% less or equal, 0.000% higher)) I believe that my simulation differs in that it uses "perfect matchmaking", without any randomness. For example, an 0-2 player will only ever get matched with another 0-2 player, and the result is that there will always be one of those players ending with an 0-3 run. I've also played around with different player distributions. For example, under the assumption that more higher-skilled players tend to play Arena (because they find it profitable), that lower-skilled players avoid Arena (more efficient to buy packs), and that there's a crop of new, unskilled players playing their free Arena run. The other distribution types I've tried are Normal (bell curve) and equal. So far, these different distributions don't seem to affect the results much in the long run, in a situation where there is perfect matchmaking. I agree that the matchmaking algorithm is the most important factor in the distribution of arena win rates. I will make my computer source code available for people to view and run. I'm currently looking into where best to host the code. Thanks, MarcoBrei for inspiring this effort. Edit: added: The source code and sample run output. If you take your assumption, there is no need for a computer simulation, since it can be solved analytically. As has been done here:
On May 08 2014 02:49 GuntherBovine wrote: If you assume that every arena match is between two decks with the same record, you can calculate how many decks achieve a certain record. Here are the chances of getting a particular record, the cumulative chance of getting that many wins and the inverse of the first column, which gives you that one out of X decks gets that many wins: 0-3 - 12.50% - 12.50% - 8.0 1-3 - 18.75% - 31.25% - 5.3 2-3 - 18.75% - 50.00% - 5.3 3-3 - 15.63% - 65.63% - 6.4 4-3 - 11.72% - 77.34% - 8.5 5-3 - 8.20% - 85.55% - 12.2 6-3 - 5.47% - 91.02% - 18.3 7-3 - 3.52% - 94.53% - 28.4 8-3 - 2.20% - 96.73% - 45.5 9-3 - 1.34% - 98.07% - 74.5 10-3 - 0.81% - 98.88% - 124.1 11-3 - 0.48% - 99.35% - 210.1 12-2 - 0.48% - 99.83% - 210.1 12-1 - 0.15% - 99.98% - 682.7 12-0 - 0.02% - 100.00% - 4096.0
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I ran my own simulation as well, and I don't think my results matter too much but I did find an interesting fact of how the distribution of luck and skill in the game.
1 run of my simulation is 10000 players playing and all players finish their runs if the games don't ends up being odd. My algorithm does flat distribution of skill into 100 bins which means equal chance of players of any skill from 0-99, about 100 players per bin. I did NOT use normal distribution mostly because skill is something that is only determined relative to others and I already use a normal distribution for deciding on who wins. Matchmaking is given on number of wins within 1 of each other, so a 7 win person can play a 6,7,8 win person and I think this is close to what blizzard uses since it will match you against people who have different record than you in arena.
For deciding who wins a game, I use the following formula: + Show Spoiler + winner = As + r A is a factor of how much skill comes into play s is the difference in skill level of the players r is a normal distributed Gaussian
For a game of pure skill, where As >>>> r: average run length is 2.89 5.3% makes it to 12 wins the average run length of the top 1% of players is 11.89 with a 79.86% win rate
For a game of about even skill and luck, where As ~ r: average run length is 2.972 1.92% makes it to 12 wins the average run length of the top 1% of players is 7.5 with a 71.49% win rate
For a game of pure luck, where As <<<<< r: average run length is 2.994 0.62% makes it to 12 wins the average run length of the top 1% of players is 2.835 with a 48.59% win rate
I just find it interesting to see how much luck is perceived in the game vs my simulation. My guess is skill is a lot more important than luck give how the win rates of players are distributed.
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