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Team Games >> 2007 One vs TheMob >> Move 40
(Message started by: UruramTururam on Sep 12th, 2008, 10:47am)

Title: Move 40
Post by UruramTururam on Sep 12th, 2008, 10:47am
We got the C&G's answer:

40w Ec4s dc5s Ec3e dc4s dc3x

Well, not very surprising...

Title: Re: Move 40
Post by RonWeasley on Sep 12th, 2008, 10:54am
Our proposed response is

40s ef4s ef3n Re3e Rc3x ce7s

I like this.  I'll entertain motions to make this move quickly.

Title: Re: Move 40
Post by UruramTururam on Sep 12th, 2008, 10:56am
I can see nothing better than the main line discussed before; so I agree with Ron we can make our move quickly.  :)

Title: Re: Move 40
Post by mistre on Sep 12th, 2008, 11:03am
I second the proposed move.

Title: Re: Move 40
Post by arimaa_master on Sep 12th, 2008, 12:40pm
Count me in for that move too!

Title: Re: Move 40
Post by The_Jeh on Sep 12th, 2008, 1:34pm
I'm all in favor, too.

Title: Re: Move 40
Post by Fritzlein on Sep 12th, 2008, 2:32pm
I'm in favor of the proposed move and in favor of moving quickly.

Title: Re: Move 40
Post by warren on Sep 12th, 2008, 2:48pm
I'm not quite ready to move yet, but I expect to be ready within 24 hours.

Update: I'm not 100% convinced that's the best move, but I haven't found anything better. I therefore currently support the motion to make the consensus move quickly.

Moving tonight seems a bit hasty to me, so I would prefer (but do not insist upon) waiting until tomorrow before moving.

Title: Re: Move 40
Post by 99of9 on Sep 12th, 2008, 10:17pm
It looks like we have a bit of choice about the last step?

Perhaps we should position a rabbit instead of the cat?  Either away from the c3 trap, or nearer to a goal.

I think the current move looks strong, but am interested in hearing alternatives.

Title: Re: Move 40
Post by Soter on Sep 13th, 2008, 12:34am

Quote:
It looks like we have a bit of choice about the last step?

Perhaps we should position a rabbit instead of the cat?  Either away from the c3 trap, or nearer to a goal.

I think the current move looks strong, but am interested in hearing alternatives


Then maybe replace ce7s with rd5e? On the other hand, I reckon that ce7s does make our goal attack a bit stronger too (albeit rather indirectly), as it allows the f7 rabbit to charge straight ahead.

Btw, do we have a decent answer to 41g Ed3e Rh1n rh4n Ch3n?

Title: Re: Move 40
Post by warren on Sep 13th, 2008, 7:19am

on 09/13/08 at 00:34:56, Soter wrote:
Then maybe replace ce7s with rd5e? On the other hand, I reckon that ce7s does make our goal attack a bit stronger too (albeit rather indirectly), as it allows the f7 rabbit to charge straight ahead.

Btw, do we have a decent answer to 41g Ed3e Rh1n rh4n Ch3n?


The advantage I see of rd5e over ce7s is that it makes it harder for him to rescue the horse if we push the horse to f5.

If he replies to 40s ... ce7s with 41g Ed3e Rh1n rh4n Ch3n, what about replying with 41s Hg4n ef4e rd5e re5s? If we play 40s ... rd5e instead, we can get to the same position after that 41g with slight variant on that 41s.

Update: I currently support 40s ef4s ef3n Re3ex rd5e. After Fritzlein's
 40s ef4s ef3n Re3e Rf3x ????
 41g Ed3e Rg1w Rf1n Da3e
 41s ef4s Hg4w Hf4n ef3n
if ????=ce7s, he can reply with
42g Rd4e Re4n Hf5e Hg5e
but if ????=rd5e, his options are more limited.

Update 2: If we end up trading his horse and a rabbit for our two dogs, leaving us with 8 rabbits and 2 cats and him with 6 rabbits a cat and a dog, that's fine for us, right?

Title: Re: Move 40
Post by Soter on Sep 14th, 2008, 2:58am

Quote:
Update 2: If we end up trading his horse and a rabbit for our two dogs, leaving us with 8 rabbits and 2 cats and him with 6 rabbits a cat and a dog, that's fine for us, right?

Calculations from Janzert's site:

Our present position( e3 rabbit alive )
FAME thinks gold is ahead by 2.51.
DAPE thinks gold is ahead by 3.24.
DAPE (empirically optimized) thinks gold is ahead by 0.12.

if e3 rabbit dead:
FAME thinks gold is ahead by 0.72.
DAPE thinks gold is ahead by 1.02.
DAPE (empirically optimized) thinks silver is ahead by 1.18.

Warren's example ( EDC + 6R vs. ecc + 8r )
FAME thinks silver is ahead by 1.72.
DAPE thinks silver is ahead by 1.84.
DAPE (empirically optimized) thinks silver is ahead by 1.95.

Title: Re: Move 40
Post by RonWeasley on Sep 14th, 2008, 3:20pm

on 09/13/08 at 00:34:56, Soter wrote:
Btw, do we have a decent answer to 41g Ed3e Rh1n rh4n Ch3n?


I suggest 41s Hg4n ef4e dg3e rh7s.

If the gold E comes to the rescue, our cat on e6 allows our d5 rabbit to run to e2. The only way for gold to block is with the E and we can collect the horse. This is another reason I like ce7s for our current move.

If the gold E pushes our cat off e6, 42s rb5e rd5e rc5e re5s and we should be able to goal using e+d+r against D+C+Rs through c3.

Title: Re: Move 40
Post by warren on Sep 14th, 2008, 9:20pm

on 09/14/08 at 15:20:38, RonWeasley wrote:
I suggest 41s Hg4n ef4e dg3e rh7s.

If the gold E comes to the rescue, our cat on e6 allows our d5 rabbit to run to e2.  The only way for gold to block is with the E and we can collect the horse.  This is another reason I like ce7s for our current move.

In that line we can send our d5 rabbit to e2 in four steps regardless of whether we do ce7s or rd5e on the current move (it transposes).  That is, in the following line the two bolded steps can be swapped:
40b ef4s ef3n Re3e Rf3x ce7s
41w Rh1n rh4n Ch3n Ed3e
41b Hg4n ef4e dg3e rh7s
42w Ee3n Ee4n Ee5e Da3e
42b rd5e re5s re4s re3s

I've encountered such transpositions in quite a few lines. What are the key lines which work out better for us with 40b ... ce7s than 40b ... rd5e? In my last post I mentioned that in Fritzlein's original line rd5e seems to work better for us than ce7s.

Title: Re: Move 40
Post by RonWeasley on Sep 16th, 2008, 5:18am
I looked at the rd5e option and I get good results with that one too.  I don't have the best lines for each.  Too many.  I think our position is a win either way.

So, due to the current lack of discussion, I propose to vote on these two options beginning this afternoon if there are no objections.

Title: Re: Move 40
Post by Fritzlein on Sep 16th, 2008, 7:10am
My concern with rd5e would be that it opens up a lane for chessandgo's d-rabbit, which gains him time if he races.  But maybe we win a race anyway, for example:

40g Ec4s dc5s Ec3e dc4s dc3x
40s ef4s ef3n Re3e Rf3x rd5e
41g Ed3e Da3n Da4n Da5n
41s ef4s Hg4w Hf4n ef3n
42g Ee3n re5n Ee4n Hf5e
42s dg3s Ch3w Cg3w Cf3x dg2n
43g Da6e Db6n cc7s cc6x Db7e
43s rh4s rh3s rh2w ce7w
44g Ee5s Ee4s Ee3s Ee2e
44s re6s re5s re4s re3s

I would never play rd5e in a live game, but in a postal game we don't have to instinctively shun risky-looking moves.  If it checks out that chessandgo loses any race, then rd5e seems to do better for us materially than ce7s.

Title: Re: Move 40
Post by Soter on Sep 16th, 2008, 11:43am
After looking at some sharper lines ( rd5e instead of ce7s ), I lean towards a moderately optimistic stance regarding  the rabbit race; maybe we should spend some time investigating this option  - we do have enough time after all.

By the way, does 40s Hg4n ef4e Ch3s dg3e hold water?

Title: Re: Move 40
Post by Fritzlein on Sep 17th, 2008, 6:11am

on 09/16/08 at 11:43:28, Soter wrote:
After looking at some sharper lines ( rd5e instead of ce7s ), I lean towards a moderately optimistic stance regarding the rabbit race; maybe we should spend some time investigating this option - we do have enough time after all.

By the way, does 40s Hg4n ef4e Ch3s dg3e hold water?

Your suggested move 40s looks about as strong as the alternatives, but the argument that we have time grows less persuasive each time we dip into reserve.  We're coming into an endgame that will be tricky even if we are up CRRR for H or we are up RR straight.  We're headed for the endgame paradox that even though our lead is clearer than ever, one blunder could be deadlier than ever.

Yes, 99of9, I think the post-mortem is premature given that one of the options on the table (and apparently the one that people are leaning towards) has barely been analyzed.  What about this line?

40s ef4s ef3n Re3e Rf3x rd5e
41g Da3n Da4n Da5n Da6e
41s ef4w Hg4w Hf4s Hf3x ee4e
42g Db6n cc7s cc6x Db7e Rd4n

Sure, we are up by two rabbits, but how strong is his goal attack relative to ours?  I don't know.  I feel like I'm voting in the dark more than I have felt in a long time, and that may just be a feature of endgames where the slightest slip is fatal.

Title: Re: Move 40
Post by warren on Sep 17th, 2008, 7:38am

on 09/17/08 at 06:11:48, Fritzlein wrote:
40s ef4s ef3n Re3e Rf3x rd5e
41g Da3n Da4n Da5n Da6e
41s ef4w Hg4w Hf4s Hf3x ee4e
42g Db6n cc7s cc6x Db7e Rd4n

Bomb thinks that line works fine for us. It suggests we reply:
42s ce7s re5s ef4n ef5w
With our elephant centralized his goal threats don't seem to work. Though as you say, it's rather close to disaster.

Title: Re: Move 40
Post by Janzert on Sep 17th, 2008, 8:04am
I finally took a quick look at what opfor likes here. For 40s at depth 12 opfor would play the proposed move with ce7s:

depth 12
time 414
nodes 31257661
qnodes 13202975
losing_moves 16
score 155
pv ef4s ce7s ef3n Re3e Rf3x w Ed3e Rh1n Da3e Db3n b rd5w rc8e Hg4n ef4e

Yay, it actually chooses one of the same moves the humans do.

Taking a look at what it thinks after the two proposed moves it looks like this (scores are from the side to move's perspective, i.e. gold for these):

40s ef4s ef3n Re3e Rc3x ce7s

depth 12
time 90
nodes 8247673
qnodes 123001
losing_moves 81
score -79
pv Da3e Ed3e Rg1n Rh1n b Hg4n ef4e rd5e rb5e w Rg2w Ee3e Ef3w dg3w df3x
depth 13
time 159
nodes 15608482
qnodes 305092
losing_moves 81
score -118
pv Da3e Ed3e Rg1n Rh1n b Hg4n ef4e rd5e rb5e w Rg2w Ee3e Ef3w dg3w df3x b Hg5w

40s ef4s ef3n Re3e Rc3x rd5e

depth 12
time 199
nodes 18998800
qnodes 173353
losing_moves 1148
score -161
pv Rh1n Da3n Ed3e Rg1n b ef4w Hg4w Hf4n ee4e w Ee3n re5w Ee4n Hf5e
depth 13
time 417
nodes 41641378
qnodes 710956
losing_moves 1148
score -244
pv Rg1w Rf1n Rc2e Ed3e b ef4w Hg4w Hf4n ee4e w Ee3n re5w Ee4n Hf5e b ef4n

Basically the above means that at a depth of 16 and 17 steps from the current position opfor prefers rd5e over ce7s. Personally though I'm still favoring ce7s since I don't trust opfor's goal racing ability at all.

Janzert

Title: Re: Move 40
Post by Janzert on Sep 17th, 2008, 8:23am
Heh, that's the first time I had the mob game window open when the move was played. It was a bit startling. :)

Janzert

Title: Re: Move 40
Post by Fritzlein on Sep 17th, 2008, 8:49am
Wow Ce7 won 6-4.  It may be that we have rejected the objectively stronger move in favor of a safer-looking move.  The only way I see out of the dilemma is increased analysis to show that the strong move really is safe, but my time was limited this past weekend, and other folks (except warren) were pretty quiet too.

Title: Re: Move 40
Post by RonWeasley on Sep 17th, 2008, 8:53am
We chose to push our cat forward 6-4.  A close vote and there was still some room for more discussion, but it seemed like much of TheMob had made up its mind.

Title: Re: Move 40
Post by mistre on Sep 17th, 2008, 10:20am
I wound up voting for rd5e after a bit more analysis.  Seemed to be the stronger move and I couldn't find a way for Chessandgo to beat us in a race.

I think we may have rushed the vote this time, but what's done is done.  ce7s shouldn't lose us the game, but it might have prevented us from a quicker win.




Title: Re: Move 40
Post by NIC1138 on Sep 17th, 2008, 5:25pm
I actually thought about the rabbit option before reading the full thread, and was happy to see other adherents. But as a junior player, I lack sophisticated arguments for it. One of them is simply the basic principle of avoiding to get your rabbits pulled by elephants! It brings bad luck, IMO. :)

I play with my guts... And I'm out of shape! But I can tell you what I feel just to throw some wood at the fire. I feel like our rabbit is in a bit of a danger, and also might be more useful at the south-east region. The cat move is good, but I think it could wait for one or two rounds.

Wouldn't it be great if we were able to fork the game to see what happens after each choice?...  ::)

Title: Re: Move 40
Post by The_Jeh on Sep 18th, 2008, 2:15pm
Just as an afterthought, I am happy with the choice to move the cat simply because it puts a second defender one step closer to c6. This saves us a step of time in case an immediate counter-attacking dog thrust is what c&g has in mind. If that is the case, this extra step will be useful if we play the tactic e->e4, H->f4; we can use it to get our dog out of the way to g4 so counter-capturing it becomes impossible. It's just an idea I have. I'll take a surer victory over a quicker one any time.

Title: Re: Move 40
Post by mistre on Sep 18th, 2008, 5:27pm
Just thought of this... thankfully it wasn't a tie.  How would we resolve with only 2 choices?

Title: Re: Move 40
Post by Fritzlein on Sep 18th, 2008, 6:28pm

on 09/18/08 at 17:27:32, mistre wrote:
Just thought of this... thankfully it wasn't a tie. How would we resolve with only 2 choices?

We could vote again while we continue to discuss.  I was certainly wavering, and others might have changed their minds as well.  Also, for the re-vote RonWeasley could have refused to close voting until there were exactly eleven voters. :)

Title: Re: Move 40
Post by NIC1138 on Sep 18th, 2008, 7:31pm

on 09/18/08 at 17:27:32, mistre wrote:
Just thought of this... thankfully it wasn't a tie. How would we resolve with only 2 choices?

We could go into overtime, and start a postal match between the two antagonizing and angry factions of The_Mob!  ;D

Title: Re: Move 40
Post by 99of9 on Sep 18th, 2008, 10:35pm
We could also allow people to cast fractional votes based on the strength of their opinion.

Title: Re: Move 40
Post by RonWeasley on Sep 19th, 2008, 12:36pm
We had a tie on an early move.  We resolved it by me flipping a galleon.  Actually I used a knut.  Harry wasn't around and I never carry a lot of cash.



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