- Jay120171
- |
- Exalted Mythic Member
Posted by: sesquipadelian
Posted by: Jay120171
They have the same win% but they are not the same consistency assuming A goes 4-1 & 4-1 while B goes 8-2. First off, their sigma is adjusted more for a streak of 2 or more games. So, Player A would have his sigma stalled or lowered twice when he broke up his streaks while B would only have his stalled or lowered once after his first loss then RAISED again after his second loss.
they do have the same consistency if looked at over the life of their careers or from the perspective of 10 games. they do not have the same consistency if you look from the perspective of 5 games.
you mention that the level of sigma adjustment is contingent upon streaks (you talk about a streak of 2 games). where did you see anything about that in the trueskill descriptions? i have seen nothing along those lines. your account would be correct based on a lot of assumptions, and those assumptions are built upon arbitrary considerations. the rank system may very well take streaks into consideration, but i doubt it, and i also doubt that it does so as you have explained.
also, what makes you think that it would view streaks as you have described? what is more valuable, having a streak of 8 wins, a streak of 2 losses, and so on? or having a streak of 4 wins, a loss, and so on? my claim is that the streakiness is irrelevant in determining skill in these cases. and, as far as i can see, the trueskill explanations do not say anything about how streakiness affects sigma or ranks.
Assumptions:
-Both players already have a high sigma because they are new to H3.
-Both players had their wins and losses to equally skilled players even though they were at different points in their career.
Facts:
-Sigma is decreased for every game played depending on the outcome along with the probability of the outcome.
--"Every match provides the system with more information about each player’s skill belief, usually driving σ down."
-Sigma is increased for every game played.
--"Before starting to determine the new skill beliefs of all participating players for a new game outcome, the TrueSkill ranking system assumes that the skill of each player may have changed slightly between the current and the last game played by each player. The mathematical consequence of making such an assumption is that the skill uncertainty σ will be slightly increased, the amount of which is, in principle, a configurable parameter of the TrueSkill ranking system. It is this parameter that both allows the TrueSkill system to track skill improvements of gamers over time and ensures that the skill uncertainty σ never decreases to zero ("maintaining momentum")."
I did make an assumption about "consecutive games" meaning consecutive wins or losses and that is probably wrong. It doesn't spell out details about streaks directly affecting sigma. It does however, explain that your sigma starts off high and is decreased after every game and increased after every game. The amount of decrease is based on the systems assumption of you winning or not. The amount of increase is a constant set by the developer.
MS also states that when you win and lose predictably, it is sure about your rank and slows your progression down. I assume this means that when you win and lose predictably, you have a low sigma because they define it as "uncertainty". It then takes a large number of games to go up or down (10 for 2 Teams of 4 Players). I assumed this was cause by your sigma getting increased because you were now winning games you shouldn't but this may be incorrect as well. It may just be you slow down because you've played a lot of games therefor your mu increases are smaller and not necessarily your sigma is low.
Yes, I assumed a player winning 8 in a row would have a higher sigma because the system figures they should lose once in a while but I cannot find a direct quote to prove it and this is the assumption we were all making. You are saying that a person winning 8/2 should be the same skill as a person going 4/1 & 4/1but there is no direct evidence to prove that is correct or incorrect and I think you will settle for nothing less.
[Edited on 12.03.2007 4:20 PM PST]