Just FYI, Rinascimento is intentionally (whether agreed by all as good or bad) not included in the points system because of the perceived initial imbalance. Every outcome for this variant results in no net change in ranking.

Amby,

Were you able to follow my explanation of where I think the problem is?

Out of curiosity, how can you tell if a variant is included in the points system?

Generally yes Leif. It seems to favour winning or drawing in mega player games (30+ players) but you get a lot less in 'normal' size games. This kind of makes sense but it should really account for point value of games. High points games make riskier games, which should be rewarded but doesn't seem to be.

Sorry maths isn't my strong point so the whole equation thing about who is expected to win impacting on the result doesn't really make sense to me. I agree with the theory but don't understand the mathematics involved.

I totally disagree on making Rinascimento worth zero. That's my point.

For anyone (whether it be me or any other player for that matter) to pull of a win in that variant as anyone other than Venice, the Pope, Naples or maybe Milan or Savoy, is worth points to recognise that effort. Yes if you win outright in Venice you should also be acknowledged with points but a lot less.

@Leif:
Mathematically it uses the SC-difference for setting the mV, thats why in a draw it does not count the end result as the difference is 0.
Non-mathematically: we removed to score the players in a draw as many high-points player would loose points if they are part of a draw with lower-rated players and there are many possibilities why you have to do this.
In http://www.vdiplomacy.com/hof.php?gameID=4761 cypeg won 800% DPoints. Bet=5, Won=40, you won 300% Bet=5, Won=15.
If you cpmpare this with the VPoints you will see it's very equal.

yebellz or someone else who's got a really good grasp of the math, can you back me up here and help me explain what's wrong with the current code in terms of a true ELO system? I'm not hugely skilled in expected value calculations and statistics.



Oli, by happenstance the numbers came out more or less believable (and as I show below can be used for a ranking system), however the math behind the calculation is, to the best of my knowledge, fundamentally wrong... that is IF the calculation is intended to be an ELO type system with expected values and actual values of player performance.


The math from the wiki makes sense for an ELO system (I've adjusted it with a few additions noted with an asterisk to refine certain calculations)

Expected result player1 (Re1) and player2:
Re1 = 1 / ( 1 + ( 10^( (Rating2 - Rating1) / 400) ) )
Re2 = 1 - Re1

Real Result Calculation:

*For PPSC survives only:
Rr1 = Pl1SCs/(Pl1SCs + Pl2SCs) (if both have 0 SCs set Rr1 = 0)
Rr2 = Pl2SCs/(Pl1SCs + Pl2SCs) (if both have 0 SCs set Rr2 = 0)
*Rr1 and Rr2 then become some number between 0 and 1

*For PPSC or WTA solo by player1:
*Rr1 = 1
*Rr2 = 0 (survive or defeat)

*For PPSC or WTA draw vs draw:
*Rr1 = 0.5
*Rr2 = 0.5

*For PPSC or WTA draw vs defeat
*Rr1 = 1 draw
*Rr2 = 0 defeat

*For WTA survive vs survive or survive vs defeat
*Rr1 = 0.5 survive
*Rr2 = 0.5 survive/defeat

*For PPSC defeat vs defeat
*Rr1 = 0.5
*Rr2 = 0.5

*Likewise CD's can be rated 0:1 against other performances


Relative Performance Calculation:
D1 = Rr1 - Re1
D2 = Rr2 - Re2

mV, gV then adjust the final score change based on player investment and map size to scale things appropriately.

scoreMatchPlayer1 = K * gV * mV * D1
scoreMatchPlayer2 = K * gV * mV * D2




When applied player vs every other player for all players this is a multiplayer extension of an Elo based system, and mV should not additionally be used to calculate any performance difference based on SC proportions between the players in this case.

D1 and D2 never end up zero (unless a player's actual performance against his opponent exactly matches his expected performance), and so the score adjustment occurs for each player against every other player every time as it should.





Now, however, since the code is different than the wiki description, I attempted to put together a description for what I think is happening in the code (not 100% sure I represented it accurately but I did my best):

---(my commentary on the validity of the calculation is displayed in this form)

Relative player skill for player1 (Re1) and player2 (Re2):
Re1 = 1 / ( 1 + ( 10^( (Rating2 - Rating1) / 400) ) )
Re2 = 1 - Re1
---(good, though this is no longer really an expected value, it results in a number between 0 and 1 and is a measure of relative player skill of sorts)

SC counts (SCc) and percentage of total SC's (SCq) are adjusted if needed as follows...
---(note that SCc as adjusted below no longer represents supply center counts, but rather, arbitrary 1 and 0 values that serve to function as a switch indicating a gradient of performances, as it were)

RESIGNS/DEFEATS
If any player resigned or was defeated set their SC totals and percentages to zero
SSc = 0
SCq = 0
---(This makes sense, they have no SC's)

CD's
If player1 CD'd then player2 gets an SC count of SCc2 = 1, unless he also CD'd in which case it is 0. The SC proportions are SCq2 = 1/# of players, unless player2 also CD'd in which case SCq2 = 0.
This case is repeated for if player 2 CD'd and player1 did or did not.
---(Basically SCc is now a flag indicating that one player who did not SC did better than another player who did, regardless of the performance of the player who did not CD.)

DRAWS
If player1 was in the draw, SCc1 = 1, SCq1 = 1/# of players in draw
If player2 was in the draw, SCc2 = 1, SCq2 = 1/# of players in draw
---(Again, SC count is no longer SC count but an arbitrary binary value of either 1 or flagging that a draw was rated a 1 over a defeat; if both players drew, each gets a 1 and their mV ends up 0 thus resulting in no score change between the two)

WTA SOLO
If player1 solo'd and game type is WTA: SCc1 = 1, SCq1 = 1 and SCc2 = 0, SCq2 = 0
likewise if player 2 solo'd
---(Here again SCc is changed to an arbitrary binary value indicating success or failure rather than SC count).

ALL OTHER CASES:
If player1 had more SC's than player2: SCc1 = 1, SCc2 = 0
Otherwise if player2 had more SC's than player1: SCc2 = 1, SCc1 = 0
Otherwise if player1's SC count is not 0 both player1 and player2 get their counts adjusted to 1: SCc1 = 1, SCc2 = 1
---(Again, basically, player1 either completely succeeds against player2 while player 2 completely loses or vice versa, even if player1 had only 1 more SC than player2. This section of the code obliterates any remaining information SCc contained about the actual SC counts and together with all the other adjustments to SCc serves to turn SCc into a binary flag rather than an SCc. At least this is consistent).

The performance flags are then calculated:
$Rr1 = ( ($SCc1 + $SCc2) > 0 ) ? ($SCc1 / ($SCc1 + $SCc2)) : 0;
$Rr2 = ( ($SCc1 + $SCc2) > 0 ) ? ($SCc2 / ($SCc1 + $SCc2)) : 0;

---(So basically from what I can tell, since SCc1 and SCc2 are always either 1 or 0,
Rr1 : Rr2 is always either 1:0 or 0:1, based on which player had the greater result of: W/D/S/E/B (Win/Draw/Size of Survive/Eliminated/Booted for CD)), for either PPSC or WTA game types.
Rr1 = 1
Rr2 = 0

For one level of finish vs another (other than equal survives) such as Draw vs Draw, Defeat vs Defeat or CD vs CD effectively:
Rr1 = 0
Rr2 = 0

Basically Rr ceases to be a measure of Real Result just as SCc has ceased to be a measure of SC count and Rr is a performance flag based on the W/D/S/E/B criteria)


mV is then calculated based on the SC proportions:
mV = abs(SCq1 - SCq2)
---(SCq is valid as a proportion of SC's for the case of defeats/resigns, and in the case of any player vs CD it is reasonable at 1/# of players thus effectively splitting all the score everyone gained against the CD'd player by number of players, though this should probably actually be (# of players - # of players that CD'd). It also looks to be valid for a WTA solo at 100% and 0% for all others, and it remains in all other cases the original SC proportion, including for PPSC solos, so in the end SCq is still essentially a valid quantity for SC proportion).


mV is then futher adjusted based on whether a player joined later (betting differently than the original players)
gV is calcualted based on victory conditions and map size
---(no detail provided here as these calculations are arbitrary scaling values that we've all more or less agreed on and work more or less as intended).


I now diverge from following the code to comment on this method as a ranking system:

So mV at this point contains all the information about relative performance between players (scaled by their share of risk in the original game), and real result is now a binary number or a flag of sorts that no longer means what it was supposed to).

Thus when you get to the equation in the code for
Ch1 = (Rr1 - Re1) * mV * gV
the quantity (Rr1-Re1) has no real meaning as Rr is now essentially a binary switch that either indicates a positive score increase or negative score increase (a score decrease rather) based on the criteria:

Win > Draw > Survive (Survives being ranked from largest to smallest) > Defeated > CD

Re1 then becomes an arbitrary value that increases or decreases the size of the score adjustment based on something approximating an expectation but since the loop isn't closed via Rr to change the score based on expected vs actual result, this isn't really an expectation any more, though it is a sort of measure of player skill going into a match.



So, it turns out Oli that your system as currently implemented behaves fairly well as a ranking system, but if the goal is a multiplayer ELO system, your system no longer is one.

Your code and calculations can be significantly simplified, if you like this current system which is basically a weighted score adjustment based on the criteria of W/D/S/E/B

Win > Draw > Size of Survive (Survives being ranked from largest to smallest) > Eliminated/Resigned > Booted for CD

with equal performances between players resulting in no score adjustment.



I am more than happy to keep your current system, but we shouldn't claim it is an ELO system any longer and I would like to request that we also get a true ELO system implemented alongside your system at some point for comparison.

This is no Elo-System for sure.
The mV and gV adjustments totally screw that, even so the multiplayer aspect (Elo is 1on1).. It's based on an Elo-system. The adjustments are needed to make the rating more or less equal to the point-system so we don't have 2 very different types, but replace the different bets with a system that trakes the strength of your opponens into account.

@Leif 2:
the quantity (Rr1-Re1) has no real meaning as Rr is now essentially a binary switch that either indicates a positive score increase or negative score increase (a score decrease rather) based on the criteria...

No. Rr1 ist still the Elo-based value (it's exactrly the same formula), Re1 is still the Elo-based value (Win/Loss, 1 or 0).
Just mV and gV are added and change the meaning of the total calculation so it matches the currently used DPoints distribution and the multiplayer aspect of the game.

@LEif 3:
Also mV is not arbitrary. Basically if a player lost to a 4-way draw he lost 1/4 of his value to each player (mV=0.25 => 4x-25=1), in a WTA he lost all to the winner (mV=1) and in a PPSC it depends on the SC's of all players (but again it all sums up to 1).

Anyone know if this system includes games which you have taken over a cd country?

From the wiki:
- Value the importance of take-overs. (If a player bet only the half the whole match is worth only half.)

Forgive me if this has already been asked. Is there a way to see individual ratings, and per game rating changes for those people outside of the HOF?

http://www.vdiplomacy.com/hof.php?userID=(your ID number)

Why reinvent the wheel which we can just use it readily? Can we adopt the FIDE point system for ranking? This will separate the Cheater who wants high rank and the fake new accounts to buff main account up. We should also not permit any high level and new account to mix together in a game.

That doesn't make sense MeepMeep. This is an open non-elitist community, we encourage players to mix with fellow members of the community. Many players who are quite talented come to this site from other sites on the web specifically to play variants, why should there be barriers in place to prevent new players to the site against playing whoever? There are already systems in place for players to restrict who they play, and these work fine.

In particular passworded games, and the Reliability Rating system.

It's not about elitism, it's all about doing all we can to reduce the incentive to cheat.

This system came about because some players who were not cheating managed to gain many points in the old system through the types of games they chose to play. Nowhere were they breaking any rules, but it became unfair on the players who had been here for a long time to suddenly see players who had only recently joined gain significant amounts of points.

The RR is good, the password is pretty good but only protect the cheaters to join game to help out but it does NOT protect the high-power players from entering lowbie games to farm for points with their cheat accounts.

The question here is: Can we do better?

This is a better system. The HoF as it stands represents shows a RANKING, while the dPoint system shows a players accumulated experience on this site. The HoF system actually provides a small incentive for players to join games that are either against players who are 'better' than them, or to avoid playing games against players who are 'worse' than them.

ie. a player who wins against players who are higher ranked than they are in the HoF gain significantly more vPoints than a player who wins against players who are ranked lower than them in the HoF. The inverse is true as well, a player who is highly ranked in the HoF looses more points if he looses against players who are ranked lower that he/she is.

does this make sense?

True, I avoid now to play games with low rank players as it will earn me literally nothing. i.e if I play with you MeepMeep in a 1v1 game, and win I will earn 0 . but if you win you will earn a hell of more points.

of course I Cannot avoid everyone especially since I like to play big variants, hence the feat is getting more difficult.

The important distinction to make is that:
vPoints is a system that emphasises RANK
dPoints is a system that emphasises EXPERIENCE

I believe we will have more good people to play online game if we have a system which emphasizes in reduce cheating. If we focus on preventing, discourage, reducing cheating a lot of problems will be fixed. Cheaters disrupt games so much causing the game to pause, and imbalanced.

@MM - please read what I have written.

@MeepMeep:

FIDE is a chess federation (not a ranking system) that uses an ELO ranking system which is exactly what we based our ranking system on (much as Webdip based the Ghost Ranking system on ELO as well) though we have several major deviations from a basic ELO system to address the fact that our games are more than 2 players and we in diplomacy have additional victory conditions for PPSC that chess doesn't have.

So, since we already use in some sense what FIDE uses, what exactly are you proposing...? Because we have already implemented many systems (including our new ranking system) to discourage cheating.

Also, your premise that by reducing cheating further we would somehow gain many more players, isn't necessarily correct. If every other diplomacy site couldn't/chose not to/was unable to address cheating, and we were the only one that was (or did the best job of it), that premise would hold up. But we aren't looking to be the biggest best site on the web. We focus on creating, implementing and playing variants. As such we aren't trying to be the top site on the web with the best ranking and most players.

"Elo" is not an acronym : it is the name of the person who invented the "Elo rating system". His name was : Arpad Elo (to be precise, originally : Árpád Imre Élő).

Hence "Elo" should not be written in capital letters.

The current points reward from the pot is not implementing the FIDE's rank reward system. I propose any high ranking person wins a game which include low rank, would get a reduced points pay-out from the pot.

Conversely, if a noob wins a game which include a high-rank, would get an increased points pay-out from the high-level player's points in the pot.

===================================
Let's clarify:
When the person win, the points in the pot is calculated separately against each opponent.

For example:

2 high level player and 1 low-bie in a game. One high-level wins the game: And the pot has 30.

The high-level player gained:
1. 10 from his/her original.
2. 10 from the other high-level.
2. 5 from the lowbie. (Need a prorated formula).

If the lowbie wins the game, the player will get.
1. 10 he/she put in.
2. 10 x 2 from the first high level.
3. 10 x 2 from the second high level.

MeepMeep - This (in a more complicated manner) is essentially what the Elo points do.

Retillion,

Thanks, yeah I play another game that uses ELAN points, (which aren't a ranking system but rather a promotion system), and since that is an acronym I keep accidentally capitalizing all of 'Elo' as well. Thanks for the correction.