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Arimaa >> Events >> 2007 Computer Championship
(Message started by: IdahoEv on Jan 8th, 2007, 2:36pm)

Title: 2007 Computer Championship
Post by IdahoEv on Jan 8th, 2007, 2:36pm
The first games were held this morning, but_Aamira vs bot_Loc, and bot_Bomb2005CC vs. bot_GnoBot.

http://arimaa.com/arimaa/wcc/2007/showGames.cgi (http://arimaa.com/arimaa/wcc/2007/showGames.cgi)

I'm uncertain which bots have seen new development this year.   Clearly Bomb and Occam are retreads.  Faerie and Zombie are new.  GnoBot is an unfinished new version still in development, 99 entered it rather than the 2006 version for variety's sake.   If anyone wants to pipe in with the development status of Aamira, Loc, and Clueless, I'm sure we'd be interested.

ROUND 1 - first two games.

Aamira* vs. Loc Aamira defeated Loc with an aggressive flooding approach (Aamira had advanced 7 of its rabbits by turn 8, for example).  It took early control of one of Loc's traps, then traded off trap control, gaining the advantage in early material trades.   Loc responded with a successful frame of Aamira's camel (this may be the only camel frame I've ever seen!) and some nearly successful goal threats, but Aamira managed to just barely defend the threats and sneak a goal through one step ahead of Loc.

GnoBot vs Bomb* In the second game, Gnobot attacked Bomb early with an E-H attack, but allowed the H to be taken hostage by Bomb's camel.  Gnobby followed that up with an unsupported camel attack on Bomb's other trap, resulting in a quick camel hostage.   With the elephant split, GnoBot lost the horse on 16w.  After an apparent horse blunder on 19b (unsupported trap attack leading immediately to capture on 20w), GnoBot's position rapidly deteriorated.

Title: Re: 2007 Computer Championship
Post by Fritzlein on Jan 8th, 2007, 10:44pm
Hey, it is fun to read game summaries when someone else writes them.  Keep up the good work!

Title: Re: 2007 Computer Championship
Post by IdahoEv on Jan 8th, 2007, 10:49pm
second two games:

Faerie* vs. clueless  Clueless began the match with its camel on the back row.   This cost it significantly when Faerie managed to pull both of clueless' horses and then attack a trap with M-D-R while holding a horse hostage with E.   With clueless' camel too marginalized to be effective within the event horizon, the ensuing scramble led to a regular loss of clueless' material.  In the end, Faerie goaled on turn 38 without having lost a piece.

Occam vs. Zombie*  Occam got into trouble quickly with an advanced H and an elephant blocked from centralizing.  Zombie's camel took control of the H, killing it a few turns later.  After that, attempts to attack Zombie's home traps resulted in a camel hostage and an MH counterattack that gave Zombie fairly solid control over three traps for the remainder of the game.  Zombie used this to slowly eliminate Occam's material, eventually winning a protracted one-rabbit endgame without having lost a piece.





Title: Re: 2007 Computer Championship
Post by omar on Jan 9th, 2007, 8:05am
Great coverage of the games Evan. Thanks for posting this.

Karl noted to Ned and I that the ratings being used in the tournament are not Dec 31st ratings but rather from Jan 7th. He also noted that the seeding won't make much of a difference since we are using triple-elimination and there won't be any byes for the first three rounds.

I looked into it and found that even though I had taken a snapshot of the ratings on Jan 1st they were overwritten when I ran the pairing for the first round on Dec 7th. A technical error on my part. I've changed the program so that this does not happen again next year.

Ned emailed me saying that since the ratings are some what arbitrary we should make a note of it and continue the rest of the tournament using this set of ratings.


Title: Re: 2007 Computer Championship
Post by omar on Jan 9th, 2007, 8:13am
When I ran the pairing program for round 2 it set one of
the games as:
 bot_Aamira vs bot_Zombie
but since Aamira played gold and Zombie played silver in round one I thought it made more sense to have the pairing be:
 bot_Zombie vs bot_Aamira

I've setup the game this way and notified Ned about it.

Title: Re: 2007 Computer Championship
Post by RonWeasley on Jan 9th, 2007, 8:59am
Color re-assignment for Zombie vs. Aamira approved.

The pairing program is, after all, a tool to help the coordinator achieve the pairing objectives stated in the rules.  If humans can do better, we take the better pairing and try to fix the pairing program.

Tournament Director

Title: Round II Report
Post by IdahoEv on Jan 10th, 2007, 5:12pm
Round II Standings:
Bomb2-0
Zombie2-0
Clueless1-1
Loc1-1
Aamira1-1
Faerie1-1
GnoBot0-2
Occam0-2

Round II Games report: (click the heading to open game viewer)

Zombie* vs. Aamira (http://arimaa.com/arimaa/games/jsShowGame.cgi?gid=45993&s=w)
I'm not at all sure how to describe this game, and I understand almost nothing that happened in the mid-game.  It began with Zombie driving its E behind one of Aamira's traps by turn 3.  This, combined with Aamira's tendency to advance several officers early, generally scrambled Aamira's line.  This quickly evolved into a very complex tactical situation that I admit I simply could not understand.  In several cases one or both bots skipped taking an obvious capture for reasons I could not fathom.   Zombie attacked one of Aamira's traps while leaving its own camel to defend a trap attacked by silver's EM combination for reasons I can't comprehend.    In the end, Zombie used a rabbit that had been pulled by Aamira to launch a goal race against a material race, but Zombie's search could not have seen the outcome of the goal race - it began the attack fourteen ply in advance of the game end.   Aamira's heavy advance of officers had left its home relatively undefended.  Giving up its camel in the process, Zombie goaled on turn 21.

Bomb* vs. Faerie (http://arimaa.com/arimaa/games/jsShowGame.cgi?gid=45994&s=w)
Faerie failed to defend to an EH attack on turn 5w, giving Bomb a free cat and a rabbit in the opening.   In the midgame, Bomb captured a camel hostage which Faerie attempted to unfreeze by advancing rabbits on the west flank.  Here, Bomb's greater search depth prevailed in a 4-ply tactical situation.  Bomb allowed Faerie to unfreeze the camel,  capture a dog, and take control of the c3 trap ...  in turn setting Faerie's elephant up to be decentralized and unable to defend the subsequent threat to Faerie's camel.   This led to the capture of a cat (pushed forward to prevent the camel capture), which weakened Faerie's defense on the east flank enough to push a rabbit through to goal on 28w.

GnoBot vs. Clueless* (http://arimaa.com/arimaa/games/jsShowGame.cgi?gid=45996&s=w)
An initial DLE opening led to a threat on one of GnoBot's dogs.  Gnobby defended the dog by sacrificing a rabbit rather than positioning its E next to the trap, possibly because it had clueless' camel pinned to the wall on row 8 and didn't want to sacrifice that position.   However, that choice led quickly to a barricade of Gnobby's phant and a hostage of the dog.  Clueless, however, was unable to capitalize on the situation for quite a while; with its camel pinned to the back wall and its elephant involved in the blockade, it was unable to rotate out or activate any powerful pieces.   Gnobby's free camel could have dominated the board, but instead it was played conservatively, stalemating the game for about 30 turns.   During the long period of mostly null maneuvering, GnoBot periodically allowed clueless to capture dogs or tighten the blockade, eventually trapping both horses inside the blockade and leaving GnoBot with very little free material.  Finally, Clueless abandoned the blockade with its elephant, capturing one cat while GnoBot suicided the other.  (?)  Bomb goaled two turns later, on 45b.

Loc* vs. Occam (http://arimaa.com/arimaa/games/jsShowGame.cgi?gid=45999&s=w)
Occam responded to an initial rabbit pull by rushing forward with emhr.  Surprisingly, it managed to keep its camel out of the way of Loc's phant, bringing up another rabbit to take shared control of bot Loc's traps and launch apparent goal threats by turn 10!  However, since no material had been lost, Loc's defense was too solid to allow any threats through, even after Occam took total control of the f3 trap.   Occam began piling up rabbits on rank 2, defended by a solid sheet of cats and rabbits, preventing any capture of the defending rabbits.  Eventually, the continuing pileup of offensive rabbits by Occam stalemated the offense but left Occam's few officers at the home traps completely vulnerable to marauding by Loc's M and E.   The ensuing scramble for position left Occam's defense too thin, and Loc sneaked through a rabbit goal on 25w, only one tactical capture having been made.   (Occam suicided two pieces in death throes the turn before goal).


Edited:  added links to the games.


Title: Re: 2007 Computer Championship
Post by jdb on Jan 10th, 2007, 9:18pm
Thanks for the great commentary. Keep up the good work!

Title: Re: 2007 Computer Championship
Post by IdahoEv on Jan 11th, 2007, 3:05am

on 01/08/07 at 22:44:04, Fritzlein wrote:
Hey, it is fun to read game summaries when someone else writes them.  Keep up the good work!


on 01/09/07 at 08:05:23, omar wrote:
Great coverage of the games Evan. Thanks for posting this.


on 01/10/07 at 21:18:20, jdb wrote:
Thanks for the great commentary. Keep up the good work!


Thanks for the support, guys.  After all of Karl's labor work reporting on the WC, I felt someone ought to do the same for the CC, even if bots don't quite generate the same degree of excitement.  :-)

Title: Re: 2007 Computer Championship
Post by chessandgo on Jan 11th, 2007, 3:11am

on 01/11/07 at 03:05:09, IdahoEv wrote:
Thanks for the support, guys.  After all of Karl's labor work reporting on the WC, I felt someone ought to do the same for the CC, even if bots don't quite generate the same degree of excitement.  :-)



I don't know if they're exciting or not, but you sure make them so ;) Thanks !

Title: Re: 2007 Computer Championship
Post by RonWeasley on Jan 11th, 2007, 7:07am
This commentary is much better than the Daily Prophet.  Rita Skeeter writes, "Aamira reflected on its dead relationship to Zombie.  Gnobot would ever be so Clueless as to Bomb the good Faerie.  Loc what happened to Occam."  I don't think she's ever been to a game.

Thanx, IdahoEv.

Title: Re: 2007 Computer Championship
Post by 99of9 on Jan 12th, 2007, 6:40pm
I know it hasn't mattered yet, and hopefully won't from now on, but...

Omar, could you schedule the games 8 hours apart so they cannot possibly interfere with each other's server load?

Title: Re: 2007 Computer Championship
Post by omar on Jan 12th, 2007, 11:32pm

on 01/12/07 at 18:40:30, 99of9 wrote:
I know it hasn't mattered yet, and hopefully won't from now on, but...

Omar, could you schedule the games 8 hours apart so they cannot possibly interfere with each other's server load?


I try to keep an eye on the games and can push back the start time of the other games if one is going for too long.

Title: Re: 2007 Computer Championship
Post by omar on Jan 12th, 2007, 11:45pm

on 01/11/07 at 03:05:09, IdahoEv wrote:
Thanks for the support, guys.  After all of Karl's labor work reporting on the WC, I felt someone ought to do the same for the CC, even if bots don't quite generate the same degree of excitement.  :-)


Hey Evan, I think you should be listed as the official event reported for the WCC. I've updated the WCC page:
 http://arimaa.com/arimaa/wcc/2007/

Thanks again for the great coverage.

Title: Re: 2007 Computer Championship
Post by 99of9 on Jan 12th, 2007, 11:49pm

on 01/12/07 at 23:32:56, omar wrote:
I try to keep an eye on the games and can push back the start time of the other games if one is going for too long.

Ah ok, I'm glad you're on top of this.  I just got worried when gnobby and occam were undoing each other's moves.

Title: Re: 2007 Computer Championship
Post by IdahoEv on Jan 13th, 2007, 11:17am
Round III Standings:

If I understand the pairings correctly, GnoBot is eliminated and Bomb gets a bye for round 4.
BotRecordDefeatedDefeated by
Bomb3-0GnoBot,Faerie,Zombie
Zombie2-1Occam, AamiraBomb
Faerie2-1Clueless, AamiraBomb
Clueless2-1GnoBot,LocFaerie
Loc1-2OccamClueless, Aamira
Aamira1-2LocZombie, Faerie
Occam1-2GnoBotZombie, Loc
GnoBot0-3Bomb, Clueless, Occam

Round III Games report: (click the heading to open game viewer)

Zombie vs. Bomb* (http://arimaa.com/arimaa/games/jsShowGame.cgi?gid=46124&s=w)
This game had an exciting and bloody opening that wound down to a bot-like stalemate through the midgame.   Zombie opened with an immediate EH attack; E forward 4 on  turn 1w, H forward 4 on turn 2w, and followed it up  with a camel advancement,  then immediately traded HR for DC (I think based on search depth that it probably only saw H for DC, which zombie's material eval would view as an  advantageous  trade) and giving up a camel hostage.  From there, Bomb used the camel hostage to continually threaten Zombie's back line with a lone camel while zombie kept advancing rabbits in an attempt keep the hostage alive and/or generate a goal threat.   Eventually, Zombie advanced too much material without generating an effective threat, and its position collapsed.


Aamira vs. Faerie* (http://arimaa.com/arimaa/games/jsShowGame.cgi?gid=46092&s=w)
Aamira's initial advance of officers led Faerie into an EMH attack.  Faerie retreated the M after Aamira took the offered H hostage.   An advance on the opposite flank allowed Faerie to abandon the H hostage in order to capture Aamira's cat and set up simultaneous threats to Aamira's camel and horse. The ensuing scramble led to a complex tactical situation in which it appears Faerie had a deeper search; Aamira lost a significant amount of material between turns 10 and 30 while Faerie gave up relatively little.   The endgame was a minor race, but Aamira had given up too many rabbits to mount a goal threat.


Occam* vs. GnoBot (http://arimaa.com/arimaa/games/jsShowGame.cgi?gid=46134&s=w)
The game was dominated by mixed tactical positions with no captures until turn 31.   Most of this time was spent with the two bots alternately breaking and  re-establishing a particular frame of one of Occam's rabbits that was pinning a horse. Occam's elephant was free to break the frame, but Gnobby's elephant kept the framing officer unfrozen and able to re-establish the frame in 2 steps each time.  This sequence was repeated in various forms for almost 40 ply in total before Occam's slow forward swarm overwhelmed GnoBot tactically.  A goal threat forced the loss of one of Gnobby's cats, reducing defense density enough for the rabbit to goal in that quadrant a few turns later.

 
Clueless* vs. Loc (http://arimaa.com/arimaa/games/jsShowGame.cgi?gid=46143&s=w)
Both bots maneuvered to gain control of the other's traps for about 20 turns. While clueless reinforced its back line, Loc preferred to scatter pieces away from its home traps.   The scattering gave clueless total control of Loc's trap space while Loc's E and M had managed to gain only shared control of clueless' traps.   Around turn 20, this led to the quick capture of several of Loc's pieces at home.  The material deficit led to an inevitable, if slow, win by clueless, who focussed entirely on capturing more material rather than generating goal threats. The moral may be that, in the face of one or two strong opponents, reinforcing a trap with many small pieces is a better strategy than scattering.

EDIT:  Descriptions of the remaining matches added.


Title: Re: 2007 Computer Championship
Post by omar on Jan 14th, 2007, 2:25pm
I just looked at the events log on the server and it seems to me that there may have been a network problem on the arimaa.com server during the clueless vs Zombie game.

1168735908 [Sun Jan 14 00:51:48 2007] move 14b received from b
1168736010 [Sun Jan 14 00:53:30 2007] move 15w received from w
1168736142 [Sun Jan 14 00:55:42 2007] move 15b received from b
1168736426 [Sun Jan 14 01:00:26 2007] move 16w received from w
1168736468 [Sun Jan 14 01:01:08 2007] w player has left
1168736469 [Sun Jan 14 01:01:09 2007] w player has left
1168736478 [Sun Jan 14 01:01:18 2007] b player has left
1168736486 [Sun Jan 14 01:01:26 2007] w player joining
1168736486 [Sun Jan 14 01:01:26 2007] w player present
1168736489 [Sun Jan 14 01:01:29 2007] b player joining
1168736489 [Sun Jan 14 01:01:29 2007] b player present
1168736615 [Sun Jan 14 01:03:35 2007] game finished with result w t

Shortly after receiving the move from clueless the
server thinks both players left and joined again a
few seconds after. This is a strong sign of a network
problem at the server.

For now I have cancled the next round that I had
previously setup. I have also notified the TD and
will wait for the official decision.


Title: Re: 2007 Computer Championship
Post by IdahoEv on Jan 14th, 2007, 4:58pm

on 01/14/07 at 14:25:36, omar wrote:
I just looked at the events log on the server and it seems to me that there may have been a network problem on the arimaa.com server during the clueless vs Zombie game.


Thanks for checking on this Omar.  I'll admit it seemed pretty unlikely to me for Zombie to timeout like that, and in offline tests it didn't particularly have trouble with that position.  

I'll wait to report on round 4 until the refereeing is completed.

Title: Re: 2007 Computer Championship
Post by Janzert on Jan 14th, 2007, 7:09pm
FYI, as I mentioned in chat, as I was watching the game live I noticed Zombie's * (seated indicator) next to it's name disappear for a second or two at the beginning of the turn where it timed out.

Is it possible to restart the game from the same position? Since the bots won't have gained any advantage of thinking the position over. Then if Zombie times out again it'll be sure that it wasn't just the network problem.

Janzert

Title: Re: 2007 Computer Championship
Post by Fritzlein on Jan 14th, 2007, 8:07pm

on 01/14/07 at 14:25:36, omar wrote:
For now I have cancled the next round that I had previously setup. I have also notified the TD and will wait for the official decision.

Interestingly, the pairings for round five should be identical whether Zombie or Clueless wins.  The only way to avoid a repeat pairing is to give Clueless the bye and pair Zombie vs. Faerie and Bomb vs. Aamira.  Then in round six, Clueless almost certainly has to play Bomb.

Title: Re: 2007 Computer Championship
Post by RonWeasley on Jan 15th, 2007, 8:43am
Since there was a game site server problem, the clueless vs. Zombie game in round 4 should be restarted from the position of the timeout.  Reserve times should be set accordingly if possible.  Otherwise, set reserve times as close as possible.

Tournament Director

Title: Re: 2007 Computer Championship
Post by omar on Jan 15th, 2007, 12:24pm
Thanks for the decision Ned.

I will try my best to restart this game from the same position with reserve times set as close to actual as possible. But after setting up the game I will have to immeadiately start the bots to start playing (otherwise the game will timeout again). Thus I will not be able to give advance notice of when the game will be continued (for those wishing to watch it live). Probably sometime later today I will get a chance to setup and continue this game.

Title: Round 4 Report
Post by IdahoEv on Jan 16th, 2007, 1:23am
Round 4 Standings:

In round 4, Occam and Loc were eliminated after losing to Aami-ra and Faerie,
respectively.
BotRecordDefeatedDefeated by
Bomb3-0GnoBot,Faerie,Zombie
Faerie3-1Clueless, Aamira, LocBomb
Clueless3-1GnoBot,Loc, ZombieFaerie
Zombie2-2Occam, AamiraBomb, Clueless
Aamira2-2Loc, OccamZombie, Faerie
Occam1-3GnoBotZombie, Loc, Aamira
Loc1-3OccamClueless, Aamira, Faerie
GnoBot0-3Bomb, Clueless, Occam

Round 4 Games report: (click the heading to open game viewer)

Aamira* vs. Occam (http://arimaa.com/arimaa/games/jsShowGame.cgi?gid=46178&s=w)
Fritzlein summarized it nicely in comments: "When you get two bots that both advance full throttle, I guess it is logical that they will run right past each other!". Both bots rushed forward with numerous pieces, ignoring opportunities to hostage or possibly capture opposing pieces, and neglecting to defend home traps. But, Aamira's rush included a rabbit supported by an elephant in a quadrant that Occam had nearly emptied in its rush.  That Occam had gained control of both Aamira's traps didn't matter at all when Aamira's one advanced rabbit goaled on turn 13.


Loc vs. Faerie* (http://arimaa.com/arimaa/games/jsShowGame.cgi?gid=46194&s=w)
This was an exciting game.  Wow.  In the opening and early mid-game, both bots used alternating threats of trades to leverage their way to greater threats, or short term "rescues" to reduce the severity of a threat.  (For example, on 7w Faerie is facing an M for h trade, but rescues the M with a dog, dooming the dog but changing the trade to a muche more advantageous D for h trade.  Loc declines the trade, rescuing the h and threatening a free D capture. Faerie responds by converting to a different D for h trade.  Loc converts this back into the original M-for-h trade).   Then, the critical moment came at turn 11w: one of those moves where a mixture of a fairly deep tactical search and luck begins to look eerily like high strategy.  Faerie accepts the M-for-h trade, making a two-step move and opting not to defend the M, which it could have done with the dog, at least long enough for the E to arrive on the scene. Instead, conserving the dog loses the camel but sets Faerie up to occupy a Loc's weaker trap the next turn with an E-D attack.  That attack triggered an uninterrupted sequence of four captures - rabbit, rabbit, cat, dog.   But the first of those captures did not occur until three turns (six ply) after it decided to abandon the M rather than reinforce with the dog ... well outside the search horizon of any bot.  As far as I understand it, Faerie could not have known that the dog had a more important use than rescuing the camel, but somehow it did.   Afterwards, the dramatic material swing made Faerie's win more or less inevitable.


clueless*  vs. Zombie (part 1) (http://arimaa.com/arimaa/games/jsShowGame.cgi?gid=46196&s=w)
The opening: clueless begins to pull a rabbit with a horse, and Zombie counterattacks with e-m.   Clueless quickly takes the camel hostage, and Zombie responds by attempting to threaten various officers (dog, horse), but Zombie's limited mobility allows them to escape.  Then, while clueless works on another rabbit pull, Zombie builds up a threat to clueless' camel and quickly converts it into an offer to trade the hostaged m for both clueless' M and H.   Clueless can't rescue both, and is forced to allow the hostaged camel to escape, possibly setting up Zombie to control a trap and/or capture a horse within two turns.

At this point, Zombie timed out.  However, the tournament director later determined that the timeout was likely caused by network or server trouble, and so the game was continued later in Part 2....


clueless * vs. Zombie (part 2) (http://arimaa.com/arimaa/games/jsShowGame.cgi?gid=46249&s=w)
The continuation of this game was unfortunately not very exciting, but it did reveal a critical flaw in Zombie:  Zombie's search routine does not check for repeated positions.   The escaped camel hostage of the first half became the center of a back-and-forth reversal as clueless and Zombie alternately made and unmade a not-quite-frame of the camel.   This situation persisted for about 12 turns until Zombie repeated a position for the third time, losing the game.

 

Title: Re: 2007 Computer Championship
Post by Fritzlein on Jan 17th, 2007, 3:55pm
Well, Faerie could have gotten a round 6 bye by winning in round 5.  Given that Zombie won instead, it looks like we must have a Zombie-Faerie rematch in round 6 while Clueless and Bomb play.  The good news for Zombie/Faerie is that the winner of their rematch will get a round 7 bye while Clueless and Bomb are forced to rematch.

Bomb is sitting pretty, needing only to win three before losing three.  I still don't think Bomb will go undefeated, but I expect it can manage better than 50% from here on out.

Title: Re: 2007 Computer Championship
Post by IdahoEv on Jan 17th, 2007, 5:31pm
Round 5 Standings:

Aamira was eliminated after losing to Bomb.
BotRecordDefeatedDefeated by
Bomb4-0GnoBot,Faerie,Zombie,Aamira
Clueless3-1GnoBot,Loc, ZombieFaerie
Zombie3-2Occam, Aamira, FaerieBomb, Clueless
Faerie3-2Clueless, Aamira, LocBomb, Zombie
Aamira2-3Loc, OccamZombie, Faerie, Bomb

Round 5 Games report: (click the heading to open game viewer)

Bomb* vs. Aamira (http://arimaa.com/arimaa/games/jsShowGame.cgi?gid=46314&s=w)
A fairly straightforward game: Aamira's forward rush got it into trouble early against Bomb's superior tactical play, with a horse loss on turn 6 and several other captures following.  The resulting lack of defending officers on Aamira's line made for an easy goal by Bomb a few turns later.

Zombie* vs. Faerie (http://arimaa.com/arimaa/games/jsShowGame.cgi?gid=46326&s=w)
In early tactical maneuvering, both bots threatened the other's camel.  Zombie converted the threat on its camel into an EMH attack on Faerie's c6 home trap. Moving up a pair of wing rabbits, Zombie was able to retain the mobility of the attacking camel and horse, freeing the elephant for other tasks as the two bots exchanged threats.   Zombie used the mobile phant to create a split, forcing Faerie to choose between its camel and a dog.   Since the dog was near the c6 trap,  Faerie's defense was fatally weakened.  Zombie moved up a dog to support the attack, took full control of the trap, and used its elephant to maintain a threat against Faerie's camel. After a few small trades, Zombie managed to push through one of the two early-advanced rabbits to goal on turn 23w.


Title: Re: 2007 Computer Championship
Post by IdahoEv on Jan 18th, 2007, 1:04pm

on 01/17/07 at 15:55:51, Fritzlein wrote:
Bomb is sitting pretty, needing only to win three before losing three.  I still don't think Bomb will go undefeated, but I expect it can manage better than 50% from here on out.


I think Bomb *will* go undefeated.  

Title: Re: 2007 Computer Championship
Post by IdahoEv on Jan 19th, 2007, 4:57pm
Round 6 Standings:

Faerie was eliminated after losing to Zombie for a second time.
BotRecordDefeatedDefeated by
Bomb5-0GnoBot,Faerie,Zombie,Aamira,Clueless
Clueless3-2GnoBot,Loc, ZombieFaerie, Bomb
Zombie4-2Occam, Aamira, Faerie x2 Bomb, Clueless
Faerie3-3Clueless, Aamira, LocBomb, Zombie x2

Round 6 Games report: (click the heading to open game viewer)

Bomb* vs. Clueless (http://arimaa.com/arimaa/games/jsShowGame.cgi?gid=46372&s=w)
As noted by Fritzlein in the game's comments, clueless gave up a horse hostage to Bomb's elephant but failed to use its own camel and other horse to capitalize on the reduced mobility of Bomb's phant.   Instead, over-cautious play allowed both those officers to get into trouble.  Clueless abandoned the hostage, losing the horse and failing to take any material in return.  A subsequent gridlocked snarl of most of the remaining material on the eastern wing (both E's, both camels, two horses) left Bomb with an unopposed horse and dog to push a rabbit through in the other corner.

Faerie * vs. Zombie (http://arimaa.com/arimaa/games/jsShowGame.cgi?gid=46375&s=w)
Zombie launched an EMH attack early, and managed to avoid getting either the M or H forked between Faerie's traps.  Faerie made an unsupported M attack that eventually led to a trade of Zombie's advanced horse for Faerie's advanced camel, and a subsequent trade of Zombie's cat for Faerie's dog.  Then in a clear demonstration of the material eval difference between the two bots, on turns 20-22 both bots opted to trade Zombie's camel for Faerie's cat and dog.   (Faerie thinks M=5000, D=1800, C=1500, while for Zombie, C+D > M in all cases).   Despite the material deficit, Faerie launched a goal threat after an injudicious rabbit advance by Zombie created a hole in his defensive line.  However, the gold rabbit didn't reach goal, and the decentralization of Faerie's elephant -- created in trying to push its own rabbit through -- allowed Zombie to generate material threats that emptied Faerie's defenses in the opposite corner.

Title: Re: 2007 Computer Championship
Post by Fritzlein on Jan 19th, 2007, 5:45pm

on 01/18/07 at 13:04:44, IdahoEv wrote:
I think Bomb *will* go undefeated.

Hmm... Only two wins to go for that.  I guess I have to hope either that Bomb's dismemberment of Clueless was a fluke, or that Zombie's dangerous threats to Bomb were not a fluke.  If Bomb wins undefeated, it will be the first time it has done so since beating just Gnobot and Occam in 2004.  Bomb lost once to Clueless in both 2005 and 2006.

Title: Re: 2007 Computer Championship
Post by IdahoEv on Jan 19th, 2007, 6:35pm

on 01/19/07 at 17:45:48, Fritzlein wrote:
If Bomb wins undefeated, it will be the first time it has done so since beating just Gnobot and Occam in 2004.


Hmm, I wasn't aware of the history.   My opinion is in part my bias based on the fact that I can't beat Bomb.   I tend to think of Bomb as invincible.    Perhaps Clueless will win the next round, and we will continue to have an interesting tournament.

Title: Re: 2007 Computer Championship
Post by DorianGaray on Jan 20th, 2007, 5:37am

on 01/19/07 at 17:45:48, Fritzlein wrote:
Hmm... Only two wins to go for that.  I guess I have to hope either that Bomb's dismemberment of Clueless was a fluke, or that Zombie's dangerous threats to Bomb were not a fluke.  If Bomb wins undefeated, it will be the first time it has done so since beating just Gnobot and Occam in 2004.  Bomb lost once to Clueless in both 2005 and 2006.

Looks like we're not making much progress, are we?  :(

Title: Re: 2007 Computer Championship
Post by Fritzlein on Jan 20th, 2007, 11:51am

on 01/20/07 at 05:37:58, DorianGaray wrote:
Looks like we're not making much progress, are we?  :(

Indeed.  In some sense Fairy/Zombie represents progress, but if an unaltered Bomb can win three straight years...

Title: Re: 2007 Computer Championship
Post by IdahoEv on Jan 22nd, 2007, 2:59am
I note that the WCC page shows that Zombie and Bomb have played a finals game.   However, I also note that they played the same sides (Zombie on gold and Bomb on silver) as they played in their round 3 game.   Given that they have not played with Bomb on gold, was this the correct pairing?

Incidentally, the play was completely identical up through 14b.   On 14w Zombie deviated by one step from the previous game, which cascaded into a different endgame.

note: I'll report on rounds 7 and 8 in the morning, I haven't been around on the weekend.

Title: Re: 2007 Computer Championship
Post by Fritzlein on Jan 22nd, 2007, 9:04am

on 01/22/07 at 02:59:56, IdahoEv wrote:
I note that the WCC page shows that Zombie and Bomb have played a finals game.   However, I also note that they played the same sides (Zombie on gold and Bomb on silver) as they played in their round 3 game.   Given that they have not played with Bomb on gold, was this the correct pairing?

The color assignment is based on the total number of times each player has played each color in the tournament.  If you add across all earlier rounds, Zombie had three gold and three silver, while Bomb had four gold and two silver.  Therefore Zombie was due gold and Bomb was due silver.  If you believe that playing gold is an advantage, then it would be an unfair advantage to Bomb to get to play gold five times in seven games.  If you believe that playing silver is an advantage, then it would be an unfair disadvantage to Bomb to have to play gold five times in seven games.

On the other hand, since gold and silver are so far statistically indistinguishable in winning percentage, evening out the color advantage may seem secondary to avoiding repeated games.  It would have been lame for Zombie to lose twice in exactly the same way.  I was very happy that Zombie deviated, and happier that Zombie's deviation was actually an improvement over its previous line.  It was just bad luck that it provoked an improved line of play from Bomb, and led to an even quicker loss for Zombie.

I personally think it is up to bot developers to prevent their bots from repeating losses within a tournament.  If a bot is dumb enough to lose twice in exactly the same way, it deserves both losses.  I believe that in computer chess tournaments, bots handle this via their opening book, i.e. if a program loses a game, it will choose a different line within its opening book for the remainder of the tournament.

Title: Re: 2007 Computer Championship
Post by RonWeasley on Jan 22nd, 2007, 9:36am
Reading the tournament rules closely I found color assignment constraints only in the tie breaker section.  While there may be justification for either color in this last game (see IdahoEv and Fritzlein above), the tie breaker rules favor the colors that were used.  Since this game has been played, I rule that the result stands.

Perhaps color assignment rules could be more explicit next year.

Tournament Director

Title: Re: 2007 Computer Championship
Post by IdahoEv on Jan 22nd, 2007, 4:10pm
Reading the rules, I agree with the TD.   Given that most of the bots are deterministic, it might be more interesting to have the pairing rules avoid repeating identical matchups, but Fritzlein makes a good point that avoiding repetition of losses should probably be on the head of the bots rather than the tournament rules.

Title: Re: 2007 Computer Championship
Post by IdahoEv on Jan 22nd, 2007, 4:39pm
The tournament is concluded, with Bomb defeating and eliminating Clueless in round 7, then defeating and eliminating Zombie in round 8.   Final standings are below.  As per the tournament rules, ties are broken by pre-tournament ratings.

Congratulations to all the developers for an excellent tournament.

Final Standings:
PlaceBotRecordDefeatedDefeated by
WinnerBomb7-0GnoBot,Faerie,Zombie (x2), Aamira, Clueless (x2)
2ndZombie4-3Occam, Aamira, Faerie (x2)Bomb (x2), Clueless
3rdClueless3-3GnoBot,Loc, ZombieFaerie, Bomb (x2)
4thFaerie3-3Clueless, Aamira, LocBomb, Zombie (x2)
5thAamira2-3Loc, OccamZombie, Faerie, Bomb
6thLoc1-3OccamClueless, Aamira, Faerie
7thOccam1-3GnoBotZombie, Loc, Aamira
8thGnoBot 0-3Bomb, Clueless, Occam

Round 7/8 Games report: (click the heading to open game viewer)

Clueless vs. Bomb* (http://arimaa.com/arimaa/games/jsShowGame.cgi?gid=46420&s=w)
Clueless opened with an EH attack and a threat on a dog that Bomb had left exposed in the initial opening.  However, Clueless failed to make god on the dog threat.  In the fight over the dog, Bomb first threatened gold's horse, then camel, leveraging these threats to keep Clueless always five or six steps away from either capturing the dog or taking control of the trap threatened by the E-H attack.   Eventually, Bomb used this to create simultaneous material threats on three of gold's pieces (20w): camel, horse, and rabbit, while clueless had no effective threats on the board. This led to a rapid cascading loss of several of gold's pieces over the next few turns.  Clueless attempted to respond with a goal race, but did not prevail.

Zombie vs. Bomb* (http://arimaa.com/arimaa/games/jsShowGame.cgi?gid=46460&s=w)
This was an identical repeat of Game 46124 (http://arimaa.com/arimaa/games/jsShowGame.cgi?gid=46124&s=w) up through turn 14b; zombie opening with an EMH attack that traded Zombie's H for Bomb's D and giving up a camel hostage.   In response, Zombie attempted to threaten a dog and develop goal threats, but with a decentralized elephant and slightly down on material it simply didn't have sufficient tactical control over the board to make good on the threats.



Title: Re: 2007 Computer Championship
Post by Fritzlein on Jan 25th, 2007, 3:43pm
I'm pleased that floating triple-elimination worked this time around.  The bottom four bots were each eliminated with losses to three different bots.  That takes away a potential criticism that a bot got unluckily paired with opponents that just happened to be able to exploit a quirk.

Yes, a round-robin would be the most fair to the lower bots, but given that the total number of games that can be played is limited by server rental time, it is better to spend the extra games on repeat pairings of the top bots than on extra mismatches which are unlikely to provide additional information.

Of course Bomb laid to rest any doubt about its dominance, beating five of the seven other bots, and beating both #2 and #3 twice.  IdahoEv wins my bet with him about whether Bomb could go undefeated.

Due to the new qualifying phase against humans, it is important that the top two bots be accurately selected, not just the top one, and I think the format did a pretty good job of that too.  Zombie clearly has bragging rights over Faerie after winning both head-to-head games.  It was only close between Clueless and Zombie for second place due to Zombie's inability to avoid repetition in an otherwise excellent position.  Quirks matter, but it was a quirk.  It reminds me of 2005 when Bomb eked out Clueless only on tiebreakers, but Bomb was clearly the better bot.

I'm glad triple-elimination worked well here, because I still hold out hope that Omar will switch the format of the World Championship to be triple-elimination as well.  ;)

Title: Re: 2007 Computer Championship
Post by IdahoEv on Jan 26th, 2007, 6:18pm

on 01/25/07 at 15:43:29, Fritzlein wrote:
Yes, a round-robin would be the most fair to the lower bots, but given that the total number of games that can be played is limited by server rental time, it is better to spend the extra games on repeat pairings of the top bots than on extra mismatches which are unlikely to provide additional information.


Just to provide a contrary view:

Given that the CC does not have the scheduling conflict problems that the WC does, and computers can be scheduled to play anytime or even started automatically by a script, I think a round robin is completely doable without increasing server rental costs.  

It wouldn't cost more because the current system  wastes a lot of time:  it prevents scheduling of a subsequent round until the previous one has finished and the TD has reviewed the results of the pairing algorithm.   If you do a round-robin, all pairings have to be completed so there's no need for that review and the games can be automated.  That saves the day-plus that currently went by in between rounds.   (No complaint, Omar - I couldn't possibly have kept up with the reporting without that day!)

Anyway, consider:  Write a script that automatically starts the next game in the queue when the last one finishes.  If anything goes wrong with a game, the TD can just rule to have a new game inserted into or appended onto the queue.

If the average bot game takes 4 hours (more than generous based on recent results), then a full round-robin of 8 bots completes in 168 hours, or 7 days.   (8 choose 2 is 28 pairings making 56 games to get both color combinations.   56*4=168.)   If I am not mistaken, Omar is already renting the two tournament servers for quite a bit longer than that.  

You could schedule them at exact times every 4 hours, which would take the full 7 days but would allow people to know in advance when a game was if they wanted to watch it live, or you could start new games immediately on completion of the others which would shorten the total required time considerably.

For 6 bots, it's 30 games = 90 hours = 3.75 days
For 8 bots, 56 games = 168 hours = 7 days
For 10 bots, 90 games = 270 hours = 11.25 days
For 12 bots, 132 games = 396 hours = 16.5 days

That's based on 4 hour games, which is generous.    This year's tournament would have been 7 bots except for the inclusion of Occam.  It seems unlikely we'd go above 10 bots next year.






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