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Team Games >> 2007 One vs TheMob >> Move 21
(Message started by: Soter on Jan 10th, 2008, 3:39pm)

Title: Move 21
Post by Soter on Jan 10th, 2008, 3:39pm
Ready for predictions & notifications

Title: Re: Move 21
Post by mdk on Jan 17th, 2008, 6:55pm
Chessandgo plays 21w Da4e Db4e Eb5e Cf2w

Title: Re: Move 21
Post by The_Jeh on Jan 17th, 2008, 8:20pm
Just to get discussion started, I'll throw out 21b ed3n Dc4w ed4w ha5s. My rationale is that it blockades the H, freezes the D, and threatens to capture the C.

Title: Re: Move 21
Post by fritzlforpresidentforpresident on Jan 17th, 2008, 10:16pm
[EDIT: Oops, I didn't see Katie was logged in instead of me.  This post is from Fritzlein.]


on 01/17/08 at 20:20:47, The_Jeh wrote:
Just to get discussion started, I'll throw out 21b ed3n Dc4w ed4w ha5s. My rationale is that it blockades the H, freezes the D, and threatens to capture the C.

At first glance, I really like this move.

Incidentally I see the first three posts in this thread are from folks not playing in the World Championship.  Perhaps you will have to carry the team for a bit.  But maybe chessandgo will be distracted too, so it will be a net Mob advantage.

Title: Re: Move 21
Post by arimaa_master on Jan 18th, 2008, 4:03am
Hmm,

21b ed3n Dc4w ed4w ha5s

looks interesting but I think it is a little bit complicated and it must be carefully examined coz we can get in trouble there.

e.g. what to play after

22w Ec5e Ed5s Ed4s Me3e  ?

(it threatens flip our camel to e3 and then we will be in trouble I guess).


Therefore I suggest to play:

21b ha5s ha4e Dc4e hb4e  

securing our position and threaten to go after deserted h5 rabbit in next moves).





Title: Re: Move 21
Post by 99of9 on Jan 18th, 2008, 6:39am
I think we should consider
21b ed3n Dd2n Cc2e mc3s

but I'm quite interested in both of the other suggestions.

Title: Re: Move 21
Post by The_Jeh on Jan 18th, 2008, 11:57am

on 01/18/08 at 04:03:49, arimaa_master wrote:
Hmm,

21b ed3n Dc4w ed4w ha5s

looks interesting but I think it is a little bit complicated and it must be carefully examined coz we can get in trouble there.

e.g. what to play after

22w Ec5e Ed5s Ed4s Me3e ?

(it threatens flip our camel to e3 and then we will be in trouble I guess).


Maybe 22b ec4e mc3n Db4n ha4e. This is a dog hostage, or maybe even a forced capture if the lines are examined completely.


Title: Re: Move 21
Post by RonWeasley on Jan 18th, 2008, 12:03pm

on 01/18/08 at 04:03:49, arimaa_master wrote:
Hmm,

21b ed3n Dc4w ed4w ha5s

looks interesting but I think it is a little bit complicated and it must be carefully examined coz we can get in trouble there.

e.g. what to play after

22w Ec5e Ed5s Ed4s Me3e  ?

(it threatens flip our camel to e3 and then we will be in trouble I guess).


To which we could respond

22b ec4e mc3n Db4n ha4e  and gets us at least a dog hostage.  (Looks like The_Jeh beat me to this!)

For the other moves:
21b ha5s ha4e Dc4e hb4e:
leaves a vulnerable gold dog that we might have to trade camels to get.  So I'm valuing this the same as 21b ed3n Dc4w ed4w ha5s.

21b ed3n Dd2n Cc2e mc3s:
How do we respond to 22w Dc4s rb3n Dc3w Ec5s?



Title: Re: Move 21
Post by arimaa_master on Jan 18th, 2008, 12:30pm

on 01/18/08 at 11:57:53, The_Jeh wrote:
Maybe 22b ec4e mc3n Db4n ha4e. This is a dog hostage, or maybe even a forced capture if the lines are examined completely.


I am still not so sure, show me continuation after
23w where first move is Ed3w (maybe 23w Ed3w Ce2e Mf3n Mf4e)

So now it looks like this:

21b ed3n Dc4w ed4w ha5s
22w Ec5e Ed5s Ed4s Me3e
22b ec4e mc3n Db4n ha4e
23w Ed3w Ce2e Mf3n Mf4e
?

Title: Re: Move 21
Post by Soter on Jan 18th, 2008, 1:08pm
Hi to everyone,


Quote:
21b ed3n Dd2n Cc2e mc3s:
How do we respond to 22w Dc4s rb3n Dc3w Ec5s?


Good question - Gold is about to take our M hostage and I don't see decent compensation for Silver.


Quote:
22b ec4e mc3n Db4n ha4e  and gets us at least a dog hostage.  (Looks like The_Jeh beat me to this!)



Hey, looks like I am the third person to discover this idea independently :) This move promises a lot, but we need some more analysis. I can't help much  as I am rather busy ( euphemistically speaking... ) and will be busy for the next two or three weeks. If I find some free time, I'm gonna add my 0.02 $.

P.S. I assume hg6e hh6w Rh5n xxxx ( dd7s? rh8s? ) is not an option, isn't it?

Title: Re: Move 21
Post by The_Jeh on Jan 18th, 2008, 1:38pm

on 01/18/08 at 12:30:35, arimaa_master wrote:
I am still not so sure, show me continuation after
23w where first move is Ed3w (maybe 23w Ed3w Ce2e Mf3n Mf4e)

So now it looks like this:

21b ed3n Dc4w ed4w ha5s
22w Ec5e Ed5s Ed4s Me3e
22b ec4e mc3n Db4n ha4e
23w Ed3w Ce2e Mf3n Mf4e
?


Doesn't 23b mc4n Db5n mc5w ed4w lose material for gold? Or is he going to gain it back later?

If 24w Ec3e Ed3n Ed4n Ed5w then
24b ec4s ec3e Cc2n Cc3x dd7s [Chessandgo loses his cat]
Then, chessandgo is burdened by the fact that we threaten to frame his dog in the b6 trap. We also threaten immediate capture of his d2 dog. It's a bit of an overload for him, I think.

Title: Re: Move 21
Post by 99of9 on Jan 18th, 2008, 4:11pm

on 01/18/08 at 12:03:54, RonWeasley wrote:
21b ed3n Dd2n Cc2e mc3s:
How do we respond to 22w Dc4s rb3n Dc3w Ec5s?

Dd3w ed4s ha5s ****
it leaves us with a vague threat on his camel, and the sentinel c2 position (though after my game with mistre, perhaps this will result in our camel hostaged)

Title: Re: Move 21
Post by arimaa_master on Jan 19th, 2008, 3:18am

on 01/18/08 at 13:38:08, The_Jeh wrote:
Doesn't 23b mc4n Db5n mc5w ed4w lose material for gold? Or is he going to gain it back later?

If 24w Ec3e Ed3n Ed4n Ed5w then
24b ec4s ec3e Cc2n Cc3x dd7s [Chessandgo loses his cat]
Then, chessandgo is burdened by the fact that we threaten to frame his dog in the b6 trap. We also threaten immediate capture of his d2 dog. It's a bit of an overload for him, I think.


23b mc4n Db5n mc5w ed4w - ouch, now I see, you are right, of course - so my 22w is not good - so

I now support
21b ha5s ed3n Dc4w ed4w  too


Title: Re: Move 21
Post by Fritzlein on Jan 19th, 2008, 9:55am

on 01/18/08 at 16:11:18, 99of9 wrote:
Dd3w ed4s ha5s ****
it leaves us with a vague threat on his camel, and the sentinel c2 position (though after my game with mistre, perhaps this will result in our camel hostaged)

99of9, I haven't looked at the specific position, but the strategic trouble with the sentinel camel is that chessandgo's horses can rumble forward without fear.  Our camel loses much of its effectiveness if it can't easily change its mind to come home and step on an encroaching horse.

Title: Re: Move 21
Post by mdk on Jan 19th, 2008, 1:26pm

on 01/18/08 at 04:03:49, arimaa_master wrote:
Hmm,

21b ed3n Dc4w ed4w ha5s

looks interesting but I think it is a little bit complicated and it must be carefully examined coz we can get in trouble there.

e.g. what to play after

22w Ec5e Ed5s Ed4s Me3e ?

(it threatens flip our camel to e3 and then we will be in trouble I guess).


Therefore I suggest to play:

21b ha5s ha4e Dc4e hb4e

securing our position and threaten to go after deserted h5 rabbit in next moves).


21b ha5s ha4e Dc4e hb4e
22w hc4w Ec5s Dd4e De4e

how do we continue? and how would we respond if chessando swarms on the east? overall i think our camel's current position leaves us vulnerable to an attack on the eastern side of the board if chessandgo can prevent material loss in the west

21b ed3n Dc4w ed4w ha5s
what if chessandgo traps our camel where it is with 22w Me3w xxxx xxxx xxxx?
i guess the three other steps would be used to begin to advance pieces on the eastern side of the board. would this be good or bad for us?




Title: Re: Move 21
Post by The_Jeh on Jan 20th, 2008, 4:22pm

on 01/19/08 at 13:26:29, mdk wrote:
21b ed3n Dc4w ed4w ha5s
what if chessandgo traps our camel where it is with 22w Me3w xxxx xxxx xxxx?
i guess the three other steps would be used to begin to advance pieces on the eastern side of the board. would this be good or bad for us?


I suppose a move like 22b ec4e Md3e ed4s xxxx would be all right. The difference between the position after this move and the position right now is that after this 22b, gold's dog is frozen and gold's horse is blockaded, resulting, I think, in a net increase in advantage for us. Now, you might notice that we can accomplish this same position immediately by playing 21b ha5s ha4e hb4w Dc4w. However, we might as well play 21b ed3n Dc4w ed4w ha5s on the off chance that Chessandgo makes an error, such as have been discussed in previous posts. Any opportunity for him to blunder is good for us.

OR... We could simply allow Chessandgo to play Me3w. After all, his camel, among other pieces, must stay there or else he loses material. We would actually have more free pieces than he to thwart off any attack, and maybe we could even start one of our own.

And finally, 22b ec4e ed4e Md3n mc3e, if playable, could get interesting.

However, I'd like some more analysis from those experts among us.

Title: Re: Move 21
Post by UruramTururam on Jan 22nd, 2008, 3:09am
How about:

21b: ha5s ha4e hb4w Dc4w ?

Or perhaps to continue swarming via:

21b: dd7s ha5s ha4e ?.?.?


(This time I had only a few moments to look at the current position so they are only initial thoughts..)

Title: Re: Move 21
Post by RonWeasley on Jan 22nd, 2008, 7:01am
Should we begin voting Wednesday morning or do we need more time?

Title: Re: Move 21
Post by The_Jeh on Jan 22nd, 2008, 9:13am

on 01/22/08 at 03:09:39, UruramTururam wrote:
How about:

21b: ha5s ha4e hb4w Dc4w ?

Or perhaps to continue swarming via:

21b: dd7s ha5s ha4e ?.?.?


(This time I had only a few moments to look at the current position so they are only initial thoughts..)


My own opinion on 21b ha5s ha4e hb4w Dc4w is addressed in my previous post.

I'm not sure about your other option.

As far as voting, I was hoping we could get some closing remarks from you, Ron, or Fritzlein, or anyone else for that matter.

Title: Re: Move 21
Post by Fritzlein on Jan 22nd, 2008, 11:01am
I should have time to analyze and comment Wednesday afternoon if not before.  But there's no need to delay the vote on that account.

Title: Re: Move 21
Post by RonWeasley on Jan 22nd, 2008, 3:42pm

on 01/22/08 at 03:09:39, UruramTururam wrote:
How about:

21b: ha5s ha4e hb4w Dc4w ?

Or perhaps to continue swarming via:

21b: dd7s ha5s ha4e ?.?.?


(This time I had only a few moments to look at the current position so they are only initial thoughts..)


I couldn't find a problem with  21b ha5s ha4e hb4w Dc4w.  It seems to expose the D and may buy us a tempo at least.

I'm not sure about the continue swarming idea.  What would we be able to hem in?

I don't like options that move our camel to d3 as this invites the E to try to fork it between c3 and f3.

The_Jeh's response to Me3w seems positionally good to me.  It drives off the M and threatens the C on c2.  From it we may try to pressure the D or loosen the west side.

I'm going to wait until Fritz's final comments before starting the vote, unless we don't get them before Wednesday afternoon.  There are at least two moves in play here and his comments could provide a significant tie breaker for some of us (meaning me).

Title: Re: Move 21
Post by UruramTururam on Jan 22nd, 2008, 5:16pm

on 01/22/08 at 15:42:31, RonWeasley wrote:
I'm not sure about the continue swarming idea.  What would we be able to hem in?


Second glance thoughts about swarming - I can see two possibilities:

21b: dd7s ha5s ha4e ce7w (planning to advance the dog)
21b: dd7s ha5s ha4e hg6e (planning to catch the wabbit)

But I prefer my former proposal mentioned also before by The_Jeh. I agree with Ron that the m->d3 moves can lead us into danger.

Title: Re: Move 21
Post by The_Jeh on Jan 22nd, 2008, 5:25pm

on 01/22/08 at 15:42:31, RonWeasley wrote:
I couldn't find a problem with 21b ha5s ha4e hb4w Dc4w. It seems to expose the D and may buy us a tempo at least.

[...]

The_Jeh's response to Me3w seems positionally good to me. It drives off the M and threatens the C on c2. From it we may try to pressure the D or loosen the west side.


I don't wish to be redundant, but since we're closing this up I thought it wouldn't hurt for me to make my argument again.

I think 21b ha5s ha4e hb4w Dc4w puts us in a good position. But, as I said in a previous post, if we play 21b ed3n Dc4w ed4w ha5s, and chessandgo plays Me3w, the move 22b ec4e Md3e ed4s xxxx puts us in almost the same position. And, based on the analysis that has been done, all responses to this 21b besides Me3w seem to be bad for Chessandgo. Therefore, I still support 21b ed3n Dc4w ed4w ha5s because it grants Chessandgo numerous opportunities to blunder, while still getting us to the same place if he plays correctly. The other move comes in a close second for me.

Perhaps 21b ha5s ha4e hb4w Dc4w gains a bit of tempo, I don't know. I do think, though, that 21b ed3n Dc4w ed4w ha5s can gain us considerable reserve time because we already know how to respond to what would appear to be c&g's best option.

Not trusting myself completely, though, I await Fritzlein's thoughts.

Title: Re: Move 21
Post by mdk on Jan 22nd, 2008, 10:02pm
I feel that I should at least offer a 4 step move involving Me3w rather than just the one step I offered originally. So how about 22w Me3w Hg3n Hg4w Hf4w or maybe Me3w Hg3n Hg4n Hg5w. These both seem to offer chances for gold to attack our position where our camel is unable to go after the advanced horse. Or am I missing some obvious tactics? It just seems to me that our camel and phant may end up tied down while gold's free horse can advance potentially along with the camel if the position is right. Just my 2 cents.


on 01/22/08 at 17:25:42, The_Jeh wrote:
I don't wish to be redundant, but since we're closing this up I thought it wouldn't hurt for me to make my argument again.

I think 21b ha5s ha4e hb4w Dc4w puts us in a good position. But, as I said in a previous post, if we play 21b ed3n Dc4w ed4w ha5s, and chessandgo plays Me3w, the move 22b ec4e Md3e ed4s xxxx puts us in almost the same position. And, based on the analysis that has been done, all responses to this 21b besides Me3w seem to be bad for Chessandgo. Therefore, I still support 21b ed3n Dc4w ed4w ha5s because it grants Chessandgo numerous opportunities to blunder, while still getting us to the same place if he plays correctly. The other move comes in a close second for me.

Perhaps 21b ha5s ha4e hb4w Dc4w gains a bit of tempo, I don't know. I do think, though, that 21b ed3n Dc4w ed4w ha5s can gain us considerable reserve time because we already know how to respond to what would appear to be c&g's best option.

Not trusting myself completely, though, I await Fritzlein's thoughts.


Title: Re: Move 21
Post by The_Jeh on Jan 22nd, 2008, 11:53pm
These are a bit harder to continue, but what do we do?

Title: Re: Move 21
Post by Fritzlein on Jan 23rd, 2008, 8:01am
After finally sitting down with this position for a while, I realize it is much more difficult than I had first anticipated.  Much of our perceived advantage was due to our long-term threats to chessandgo's dog.  Now that he is threatening to relieve that pressure by circulating his dog from the west to safety in the east, we are hard-pressed to demonstrate any advantage.

Part of the trouble is that our elephant is currently on its best square on d3.  If we use it to contain gold's dog, my superficially favorite move, we cede an excellent square.  My first thought on seeing chessandgo's move was that he had wasted time, but I have now changed my mind.  His move was first-rate as usual, and puts us in a bind.

I will create an analysis tree from all current suggestions today, but first let me throw another option into the mix.  The time may have come at last for us to threaten chessandgo's advanced rabbit with 21b hg6e hh6w Rh5n rh8s.  The fourth step is rh8s insteaed of rg7e so that his camel can't make four steps to g5, freezing our horse.  Chesssandgo's elephant can't defend f6 without losing material in the west.  If either his horse or camel defend g6, it may create tactical opportunities for us.  The rabbit pull is at least worth serious consideration.

[EDIT]
Oh, I see now that Soter beat me to it.


on 01/18/08 at 13:08:55, Soter wrote:
P.S. I assume hg6e hh6w Rh5n xxxx ( dd7s? rh8s? ) is not an option, isn't it?

Title: Re: Move 21
Post by mdk on Jan 23rd, 2008, 11:08am
Just thought I should throw out some possible moves for gold in response to 21b hg6e hh6w Rh5n rh8s.

22w Me3n Me4n Me5n Hg3n ... This would be extremely sharp and unless i am missing an obvious tactic lines would need to be worked out to see who ends up ahead. Also 22w Me3n Me4n Me5n Rf1n and 22w Me3n Me4n Me5 Ce2e may be worth mentioning.

22w Hg3n Hg4n Hg5w xxxx where the last step could be Me3n, Rf1n, or Ce2e.


on 01/23/08 at 08:01:52, Fritzlein wrote:
After finally sitting down with this position for a while, I realize it is much more difficult than I had first anticipated. Much of our perceived advantage was due to our long-term threats to chessandgo's dog. Now that he is threatening to relieve that pressure by circulating his dog from the west to safety in the east, we are hard-pressed to demonstrate any advantage.

Part of the trouble is that our elephant is currently on its best square on d3. If we use it to contain gold's dog, my superficially favorite move, we cede an excellent square. My first thought on seeing chessandgo's move was that he had wasted time, but I have now changed my mind. His move was first-rate as usual, and puts us in a bind.

I will create an analysis tree from all current suggestions today, but first let me throw another option into the mix. The time may have come at last for us to threaten chessandgo's advanced rabbit with 21b hg6e hh6w Rh5n rh8s. The fourth step is rh8s insteaed of rg7e so that his camel can't make four steps to g5, freezing our horse. Chesssandgo's elephant can't defend f6 without losing material in the west. If either his horse or camel defend g6, it may create tactical opportunities for us. The rabbit pull is at least worth serious consideration.

[EDIT]
Oh, I see now that Soter beat me to it.


Title: Re: Move 21
Post by The_Jeh on Jan 23rd, 2008, 12:13pm
I'm now becoming interested in Arimaa_master's original 21b ha5s ha4e Dc4e hb4e. The main reason is that we have an extra piece defending b3 so that our elephant is more mobile, we threaten to capture the cat, and the gold dog jams up the works if chessandgo wants to fork our camel. But there may be other perks as well that I don't have time to write about right now.

Title: Re: Move 21
Post by Fritzlein on Jan 23rd, 2008, 12:55pm

on 01/23/08 at 11:08:39, mdk wrote:
Just thought I should throw out some possible moves for gold in response to 21b hg6e hh6w Rh5n rh8s.

22w Me3n Me4n Me5n Hg3n ... This would be extremely sharp and unless i am missing an obvious tactic lines would need to be worked out to see who ends up ahead. Also 22w Me3n Me4n Me5n Rf1n and 22w Me3n Me4n Me5 Ce2e may be worth mentioning.


I think we can beat the super-sharp line, but against the tamer camel advance I can't do better than equality.  I'll look at the other options to see if they appear better for us than an even game.


21b hg6e hh6w Rh5n rh8s
.    22w Me3n Me4e Mf4n Rf1n
.    .    22b ed3e ee3n ee4e mc3e
.    .    .    23w Ec5e Ed5s rb3n Ha3e
.    .    .    .    23b ha5e hb5e Dc4s hc5s
.    .    .    .    .    24w Ed4e Ee4n Mf5e Mg5e
.    .    .    .    .    .    24b ef4e eg4n eg5s Mh5w
.    .    .    .    .    .    .    25w Ee5w Ed5s md3e Ed4s
.    .    .    .    .    .    .    .    25b Mg5w eg4n Mf5n Mf6x eg5w
.    .    .    .    .    .    .    .    .    26w me3e mf3x Ed3e Ee3w Ed3n (=)
.    .    .    .    .    24w md3e Ed4s Hb3w Dc3w
.    .    .    .    .    .    24b Mf5n Mf6x ef4n ef5s ce7s
.    .    .    .    .    .    .    25w Ed3w Ec3e hc4s hc3x Rf2n
.    .    .    .    .    .    .    .    25b ce6s ce5s Rf3s me3e (=+)
.    22w Me3n Me4e Mf4n Hg3n
.    .    22b ed3e ee3n ee4e mc3e
.    .    .    23w Ec5e Ed5s Rg1n Rg2n
.    .    .    .    23b ha5e hb5s rb3e hb4s
.    .    .    .    .    24w Hg4n Mf5w Me5n Hg5w
.    .    .    .    .    .    24b Hf5n ef4n Dd2s md3s (-+)
.    .    .    23w Ec5e Ed5s rb3n Ha3e
.    .    .    .    23b ef4w Hg4w Hf4s Hf3x ee4e (-+)


Title: Re: Move 21
Post by Fritzlein on Jan 23rd, 2008, 1:28pm

on 01/22/08 at 17:25:42, The_Jeh wrote:
Perhaps 21b ha5s ha4e hb4w Dc4w gains a bit of tempo, I don't know. I do think, though, that 21b ed3n Dc4w ed4w ha5s can gain us considerable reserve time because we already know how to respond to what would appear to be c&g's best option.

As I look at it more, we might well gain reserve time by heading back to d3 with our elephant the next move, but it looks like it would lose us a bunch of tempo on the board.  Even something like this is possible:

21b ed3n Dc4w ed4w ha5s
.    22w Me3w Hg3n Hg4n Hg5w
.    .    22b ec4e Md3e ed4s dd7s
.    .    .    23w Ec5s Rf1n Hf5w He5w

But as I look more at this 21b + 22w, I simply don't see how to make progress other than by going back to d3 to threaten a takeover of c3.  The threat to chessandgo's dog in c6 is meaningless unless his elephant is tied to the defense of c3, but at soon as his camel takes d3, his elephant isn't tied to the defense of d3.

I'm going to reverse my initial enthusiasm for this move.  In fact, it looks to me now like we might even be losing if we play it, so that I would prefer the mere equality of pulling the h-rabbit.

Title: Re: Move 21
Post by Fritzlein on Jan 23rd, 2008, 1:39pm
I am slowly beginning to panic about our position.  Pulling the dog with the horse also looks too slow.  Possibly chessandgo doesn't need his elephant to defend the dog, because he has time to bring a horse around:

21b ha5s ha4e hb4w Dc4w
.   22w Ec5s Rf1n Hg3n Hg4n
.   .   22b Db4n ha4e Db5n hb4n
.   .   .   23w Hg5w Hf5w He5w Hd5n (+=)

Why didn't I see troubles looming earlier?  Since I don't like either of the front-runners, I'm going to look at some less popular alternatives.

Title: Re: Move 21
Post by Fritzlein on Jan 23rd, 2008, 1:43pm

on 01/23/08 at 12:13:22, The_Jeh wrote:
I'm now becoming interested in Arimaa_master's original 21b ha5s ha4e Dc4e hb4e.

What did you have in mind after the already-proposed refutation?

21b ha5s ha4e Dc4e hb4e
.    22w hc4w Ec5s Dd4e De4e (+=)

I don't see a good follow-up, but I may be missing something.

Title: Re: Move 21
Post by Fritzlein on Jan 23rd, 2008, 2:14pm
In light of my worries about already-proposed moves, I took a look at something else that hadn't been suggested, namely pushing the dog to b4 with our camel.  It's all about saving time.  After brief examination, I don't think chessandgo can afford to push our camel east twice.  Apparently he also can't afford to push our camel back into the trap.  Therefore he would likely push our camel east one time, which lets it loop back around and restart the dance.  I wouldn't suggest this if we had another move that looked really strong, but as it stands, we may be best off plunging back into the maneuvers of the previous half-dozen moves.

21b Dc4w mc3n ha5s dd7s
.    22w mc4e Ec5s rb3e Db4s
.    .    22b md4n md5w dd6w mc5w (?)
.    22w mc4e Ec5s rb3e Ha3e
.    .    22b md4n md5w dd6s mc5w (?)
.    22w mc4s Ec5s Rf1n Hg3n
.    .    22b Db4n ha4e Db5n hb4n (-+)
.    22w mc4e Ec5s md4e Ec4e
.    .    22b ed3w ec3e Cc2n Cc3x hg6s (-+)

Title: Re: Move 21
Post by Fritzlein on Jan 23rd, 2008, 2:35pm

on 01/18/08 at 16:11:18, 99of9 wrote:
Dd3w ed4s ha5s ****
it leaves us with a vague threat on his camel, and the sentinel c2 position (though after my game with mistre, perhaps this will result in our camel hostaged)

Perhaps we could avoid giving up the camel hostage, but we would have to be so worried about it that we couldn't get anything else done.  Also, his horses would become fearless.  I don't know what our plan would be after the following line:

21b ed3n Dd2n Cc2e mc3s
.    22w Dc4s rb3n Dc3w Ec5s
.    .    22b Dd3w ed4s ha5s dd7s
.    .    .    23w Rc1e Rf1n Hg3n Hg4n (+=)

Title: Re: Move 21
Post by The_Jeh on Jan 23rd, 2008, 2:49pm

on 01/23/08 at 13:43:11, Fritzlein wrote:
What did you have in mind after the already-proposed refutation?

21b ha5s ha4e Dc4e hb4e
. 22w hc4w Ec5s Dd4e De4e (+=)

I don't see a good follow-up, but I may be missing something.


I had forgotten about that refutation. All my attempts to respond so far either turn out bad or get extremely sharp. I'm afraid you're right about what we should do. No one said playing c&g would be easy.




Title: Re: Move 21
Post by The_Jeh on Jan 23rd, 2008, 3:10pm
What would Bomb have us do?

Title: Re: Move 21
Post by Soter on Jan 23rd, 2008, 3:12pm

Quote:
Part of the trouble is that our elephant is currently on its best square on d3.  If we use it to contain gold's dog, my superficially favorite move, we cede an excellent square.


But is this square ( and appropriate complementary squares on the board ) ALWAYS the best place for a phant? I'm not a first-rate player for sure, and I possess very limited knowledge about peculiarities of Arimaa strategy, but it seems to me that there must be some exceptions to the rule...


Quote:
I will create an analysis tree from all current suggestions today, but first let me throw another option into the mix.  The time may have come at last for us to threaten chessandgo's advanced rabbit with 21b hg6e hh6w Rh5n rh8s.  The fourth step is rh8s insteaed of rg7e so that his camel can't make four steps to g5, freezing our horse.  Chesssandgo's elephant can't defend f6 without losing material in the west.  If either his horse or camel defend g6, it may create tactical opportunities for us.  The rabbit pull is at least worth serious consideration.

[EDIT]
Oh, I see now that Soter beat me to it.


Haven't analysed much but equal trade is IMHO all we can hope for if c&g attacks our trap in return. I really would like to be wrong.

I wish I could help you, but got little time. I'll be more active in February.

P.S. One small suggestion: maybe we should "evangelize" a bit  and ask players to join the cause? The more eyes scanning the board the better - especially when uncertanity rules and position is not clear.




Title: Re: Move 21
Post by RonWeasley on Jan 23rd, 2008, 3:30pm
I don't see a refutation of the rabbit pull.  Can someone repeat it please?  If not, then I feel better about not finding one myself and we can vote for it.

Title: Re: Move 21
Post by mdk on Jan 23rd, 2008, 3:48pm

on 01/23/08 at 15:30:55, RonWeasley wrote:
I don't see a refutation of the rabbit pull. Can someone repeat it please? If not, then I feel better about not finding one myself and we can vote for it.


I think Fritz is worried that at the very best he can find is a line where we are about equal. Which means there may be some better move that deviates from the line he provided where the best result leaves us behind. I'm not sure that he has found an outright refutation. I hope I am expressing things correctly Fritz. Please correct me if I am not.

Title: Re: Move 21
Post by mdk on Jan 23rd, 2008, 4:03pm
Also no refutation has been offered to
21b hg6e hh6w Rh5n rh8s
22w Hg3n Hg4w Hf4n Rf1n

Title: Re: Move 21
Post by Fritzlein on Jan 23rd, 2008, 4:07pm
Right, mdk.  After

21b hg6e hh6w Rh5n rh8s
.    22w Me3n Me4e Mf4n Rf1n

I think we are equal, and will probably end up trading MR for MR.  Maybe someone can find better for us, but I can't.  Also I haven't yet looked at 22w Rf1n Hg3n Hg4n Hg5w.  That latter move would probably force us to play Dc4w mc3n ha5s xxxx, which is my current favorite for this move.

Title: Re: Move 21
Post by Fritzlein on Jan 23rd, 2008, 4:30pm

on 01/23/08 at 15:10:41, The_Jeh wrote:
What would Bomb have us do?

depth 10: ha5n ha6e ed3n mc3e +0.27
depth 11: ha5s ha4e Dc4e hb4e +0.65
depth 12: ha5s ha4e rg7e dd7s +1.06
depth 13: ha5s ha4e ed3n ed4s +0.60
depth 14: rg7e ed3n mc3e Cc2n +0.61
depth 15: rg7e ed3n mc3e Cc2n +0.08

I'll let it run overnight and update this post with the results, but I'm not impressed so far.

Title: Re: Move 21
Post by Fritzlein on Jan 23rd, 2008, 4:39pm

on 01/23/08 at 15:30:55, RonWeasley wrote:
I don't see a refutation of the rabbit pull.

Hmm, my refutation was 22w Me3n Me4e Mf4n Rf1n, but now I seem to have refuted my refutation with 22b ha5s ha4e ed3n mc3e.  In fact, it seems that 22b is rather difficult to meet for _any_ move that saves the rabbit.

21b hg6e hh6w Rh5n rh8s
.    22w Me3n Me4e Mf4n Rf1n
.    .    22b ha5s ha4e ed3n mc3e
.    .    .    23w Mf5e Mg5w hg6s Rh6w
.    .    .    .    23b rb3e hb4s ed4e ee4e
.    .    .    .    .    24w Ec5e Ed5s md3e Ed4s
.    .    .    .    .    .    24b rh7s rh6s Rg6e hg5n (-+)

Somebody double-check me here, but the rabbit pull has gone way up in my estimation.  I'll double-check some of mdk's other suggested moves for Gold after the rabbit pull.

[EDIT]

My idea for 22b can be avoided if gold charges a camel straight up the middle, but then Gold has other problems.  I'm beginning to think that if we pull the h-rabbit, Gold can't afford to use his camel to save it, he would have to try with the horse if anything.

21b hg6e hh6w Rh5n rh8s
.    22w Rf1n Me3n Me4n Me5n
.    .    22b ed3n ed4e ee4n mc3e
.    .    .    23w Ec5e Ed5s md3e Ed4s
.    .    .    .    23b Me6e Mf6x ee5n ee6w ed6s
.    .    .    .    .    24w me3e mf3x Ed3e Dc4s Ee3w
.    .    .    .    .    .    24b ed5s ha5s ha4e hb4e (=+)
.    .    .    .    .    24w me3e mf3x Ed3e rb3e rc3x Ha3e
.    .    .    .    .    .    24b ed5s Dc4n ed4w dd7s (=+)
.    .    .    23w Ec5e Ed5s rb3n Ha3e
.    .    .    .    23b Me6e Mf6x ee5n ha5e rb4w
.    .    .    .    .    24w md3w mc3x Ed4s Ed3n Dc4s
.    .    .    .    .    .    24b hg6s Rh6w Rg6w Rf6x hg5n (=+)
.    .    22b ed3n mc3e ha5s ha4e
.    .    .    23w Me6w Md6w Mc6w cc7s cc6x (+-)

Title: Re: Move 21
Post by Fritzlein on Jan 23rd, 2008, 5:07pm

on 01/22/08 at 17:16:56, UruramTururam wrote:
Second glance thoughts about swarming - I can see two possibilities:

21b: dd7s ha5s ha4e ce7w (planning to advance the dog)

I am afraid that if chessandgo gets his dog safely to the east, we will not be able to generate any threats while he has time to improve his position.

21b dd7s ha5s ha4e ce7w
.    22w Dc4e Ec5s Rf1n Hg3n (+=)



Quote:
21b: dd7s ha5s ha4e hg6e (planning to catch the wabbit)

This has the same time-losing possibility as above, and additionally offers a tempting target square for his horse.

21b dd7s ha5s ha4e hg6e
.    22w Rf1n Hg3n Hg4n Hg5n

Title: Re: Move 21
Post by Fritzlein on Jan 23rd, 2008, 6:22pm
If we pull the rabbit and he defends with his horse, I get into some pretty crazy lines, but the main line remains equality after trading HR for HR.  Obviously there is a ton I am not seeing, but I have to guess that it is as likely for one side as the other to have a killer move, because I kept changing my mind about who was winning.


21b hg6e hh6w Rh5n rh8s
.    22w Hg3n Hg4n Hg5w Rf1n
.    .    22b ed3n mc3e ha5s ha4e
.    .    .    23w rb3e Ha3e Me3e Mf3e
.    .    .    .    23b md3e rc3x me3n me4e ed4n
.    .    .    .    .    24w Dc4s Dc3e Ec5s Ce2n
.    .    .    .    .    .    24b Hf5n Hf6x mf4n hg6w Rh6w
.    .    .    .    .    .    .    25w Ec4n hb4e hc4s hc3x Ec5s
.    .    .    .    .    .    .    .    25b hf6w Rg6w Rf6x mf5n he6w (=)
.    .    .    .    .    24w Mg3n Mg4n hg6w Mg5n
.    .    .    .    .    .    24b hf6w ed5e Hf5n ee5e
.    .    .    .    .    .    .    25w Ec5e Ed5e he6w Ee5n
.    .    .    .    .    .    .    .    25b mf4w me4w Dc4n md4w
.    .    .    .    .    .    .    .    .    26w Ee6s Ee5w Dc5w Hf6w
.    .    .    .    .    .    .    .    .    .    26b Db5n hb4n mc4n mc5n (=+)
.    .    .    .    .    .    24b ed5e Hf5e ee5e mf4e
.    .    .    .    .    .    .    25w Dc4s Ec5e Ed5e Ee5n
.    .    .    .    .    .    .    .    25b mg4s mg3s Rf2n Rf3x mg2w (unclear)
.    .    .    .    23b ed4e ee4e Hf5n Hf6x ef4n
.    .    .    .    .    24w Ec5e Ed5s md3e rc3x Ed4s
.    .    .    .    .    .    24b Dc4n hb4e Dc5n Dc6x hc4n
.    .    .    .    .    .    .    25w Ed3w me3w Ec3n md3w mc3x (+=)
.    .    .    23w rb3e Ha3e Hf5w He5w
.    .    .    .    23b rb8s rb7s dd7s ra8s (=+)



Title: Re: Move 21
Post by Fritzlein on Jan 23rd, 2008, 6:31pm
Right now it is a tossup for me between 21b hg6e hh6w Rh5n rh8s, which can lead to wild lines with apparently equal chances, and 21b Dc4w mc3n ha5s dd7s, which leads to tame lines which are unclear.  One thing is for sure, though: I no longer think we are winning.  Rather I think I have no clue what is happening.  :P

The team can take as long it likes to pick apart my analysis, but I'm ready to vote.  Don't wait on any more analysis from me; I don't know when it would be forthcoming if you did.

Title: Re: Move 21
Post by mdk on Jan 23rd, 2008, 10:37pm
Thanks for all the analysis Fritz. I don't have time to look at it all now but I'll try and get a chance sometime tomorrow. I hope other people will do the same. As for voting at this point I'm not really sure whether there is any point in waiting much longer. It seems pretty clear to me that whatever move we play we won't be too sure of what is actually going on :P

Title: Re: Move 21
Post by Fritzlein on Jan 24th, 2008, 2:47pm
Thanks, mdk.  It was fun to have an Arimaa day.  I haven't done any more analysis, but after letting yesterday percolate I have a pretty clear preference for the rabbit pull.  Like you said earlier, we should embrace wild lines rather than shunning them, since a group of people should be less likely than an individual to suffer from tactical blindness.  Plus, even if we emerge from this mess with equality, we should be happy.

Title: Re: Move 21
Post by mdk on Jan 24th, 2008, 7:14pm
yes after looking through all the analysis i'm liking the rabbit pull most too at the moment. i'm glad i actually had time for the first time in a while to significantly contribute. I finished my midterms today so I should be able to contribute pretty regularly now

Title: Re: Move 21
Post by RonWeasley on Jan 25th, 2008, 3:43pm
All who voted were swayed by the rabbit pull arguments.  But only 8 voted, which may mean those unsure decided not to vote.  I'll admit, this was one of the harder choices we've made.  Remember, it's OK to vote more than one move in the number one slot if you really don't think you can choose only one.

Title: Re: Move 21
Post by Fritzlein on Jan 25th, 2008, 6:23pm
For the record:

   .    .    .    .    .    .    .    .    .    .   1. 2. 3. 4. 5. 6. 7. 8.
1. hg6e hh6w Rh5n rh8s (pull R, r->h7) .    .    .    -  8  6  6  7  8  8  7
2. Dc4w mc3n ha5s dd7s (push D with m, h->a4, d->d6)  0  -  4  3  4  6  6  6
3. ed3n Dc4w ed4w ha5s (push D with e, h->a4)    .    2  3  -  5  6  6  6  7
4. ha5s ha4e hb4w Dc4w (pull D with h) .    .    .    2  4  2  -  4  7  7  6
5. ha5s ha4e Dc4e hb4e (push D with h) .    .    .    1  3  1  2  -  6  6  6
6. dd7s ha5s ha4e ce7w (d->d6, h->b4, c->d7).    .    0  1  1  0  1  -  3  4
7. dd7s ha5s ha4e hg6e (d->d6, h->b4, h->h6).    .    0  1  1  0  1  2  -  4
8. ed3n Dd2n Cc2n mc3s (pull D, push C).    .    .    1  1  0  1  1  1  1  -


At least two voters didn't have the rabbit pull first!  It makes me happy that people vote against my recommended move.  That way I don't have to conceal my true opinion.



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