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Team Games >> 2007 One vs TheMob >> Move 18
(Message started by: Fritzlein on Nov 28th, 2007, 9:49pm)

Title: Move 18
Post by Fritzlein on Nov 28th, 2007, 9:49pm
18w is a move where chessandgo's most direct choices don't seem to help him that much, so we can expect something more subtle and positional.  The odds are in favor of him not choosing one of the three moves in the tree.  Still, here they are for what it is worth:

17b hb5e md5s Dc4w md4w
.    18w Ed6s hc5n Ed5w Db4w
.    .    18b mc4w Da4n mb4w hc6w
.    .    .    19w Ec5w Eb5s ma4s Eb4w
.    .    .    .    19b hb6w ha6e Da5n dd7s
.    .    .    .    .    20w Ea4n Da6n Ea5s Rb1n
.    .    .    .    .    .    20b hb6n hb7s Da7e ra8s
.    .    .    .    .    .    .    21w Hb3n Hb4n Ea4e Eb4s
.    .    .    .    .    .    .    .    21b hb6w Db7s Db6e Dc6x ha6e (=+)
.    .    .    19w Ec5s Ec4w Eb4n ma4e
.    .    .    .    19b hg6e hh6w Rh5n dd7s (=+)
.    18w Ed6s Ed5n hc5e Db4w
.    .    18b mc4n hd5s hd4w rb8s
.    .    .    19w Ed6s Ed5n mc5e Da4s
.    .    .    .    19b hc4e md5w hd4w rb7s (=+)
.    .    18b mc4w Hb3w mb4s rc8e
.    .    .    19w hd5s Ed6s Ed5w Ec5s
.    .    .    .    19b mb3n rc3w rb3s hd4n
.    .    .    .    .    20w Ec4n mb4e Ha3e Da4e
.    .    .    .    .    .    20b dd7s hd5s Db4n mc4w (?)
.    .    .    .    .    20w Da4n Ha3e mb4w Ec4w
.    .    .    .    .    .    20b hd5w hc5w dd7s dd6s (?)
.    .    .    .    19b mb3s rc3w Cc2n mb2e
.    .    .    .    .    20w rb3n Cc3w Cb3s Ha3e (+=)
.    18w Ed6s Ed5s hc5e Db4w
.    .    18b dd7s hd5w mc4w hc5w (=+)


Title: Re: Move 18
Post by Soter on Dec 5th, 2007, 3:42pm
Jean's decision: Ra2e Ed6s Db4w Da4s

Title: Re: Move 18
Post by Fritzlein on Dec 5th, 2007, 4:12pm
Surprise!  Now we have no tree.  My first thought: 18b hc5w hb5w ha5s mc4w.

Title: Re: Move 18
Post by mdk on Dec 5th, 2007, 5:58pm

on 12/05/07 at 16:12:08, Fritzlein wrote:
Surprise!  Now we have no tree.  My first thought: 18b hc5w hb5w ha5s mc4w.


This move was my first thought as well and I don't see any forcing response for gold or any better move for us. I think there may be a chance that we can gain some significant reserve time on this move

Title: Re: Move 18
Post by Fritzlein on Dec 5th, 2007, 6:38pm
Now that computers are explicitly allowed, I had to check...  Bomb's first inclination is 18b mc4w mb4n Hb3n rc3w.  Actually that is Bomb's only inclination so far, from 4-step search up to 11-step search.  Bomb has chosen a move and is sticking with it, evaluating the position as essentially even.

I think this move is strategically poor.  After chessandgo replies 19w Ed5s Ed4w rb3e Hb4s, we are worse off than at present.  We can't charge with our camel since our horse is not in front protecting it, and we can't get our horse out in front because the camel is in the way.  We have lost time in our general objective of getting the gold elephant so distracted in the west that we can take his rabbit for free in the east.

Of course, Bomb thinks its move is gaining ground by getting the silver camel to safety.  It is a move worth considering if attacking moves seem to get our camel in unacceptable trouble.  For the moment, however, I think Bomb is just short-sighted, and not able to see that a camel advance by us won't necessarily give up the camel hostage, but could eventually buy us time for our g6-horse to capture the h5-rabbit in f6.

I'll let Bomb run overnight to give it a chance to change its mind, but I already suspect Bomb is going to be useless in the near term.  It's just going to want to retreat our camel, since that's all the strategy its pea brain can hold.

Title: Re: Move 18
Post by RonWeasley on Dec 5th, 2007, 8:10pm
If he responds 19w Ed5s Ed4w mb5n Ec4w, do we pull the h5 rabbit or do we run our own rabbits up the a and b files?

Title: Re: Move 18
Post by Fritzlein on Dec 5th, 2007, 9:18pm

on 12/05/07 at 20:10:22, RonWeasley wrote:
If he responds 19w Ed5s Ed4w mb5n Ec4w, do we pull the h5 rabbit or do we run our own rabbits up the a and b files?

I was thinking we should try to capture his h-rabbit at that point.  In the few lines I played out, it can get tricky if he defends f6 with his horse, since our camel and elephant are both occupied, but it seems that we have a slight edge in the ensuing mess.  

Title: Re: Move 18
Post by arimaa_master on Dec 6th, 2007, 7:09am
Just to throw out my first inclination:

18b cc7s dd7w hc5w ce7w


But I admit that suggested: 18b hc5w hb5w ha5s mc4w

seems to be better.



Title: Re: Move 18
Post by Fritzlein on Dec 6th, 2007, 8:38am

on 12/05/07 at 18:38:52, Fritzlein wrote:
I'll let Bomb run overnight to give it a chance to change its mind, but I already suspect Bomb is going to be useless in the near term.  It's just going to want to retreat our camel, since that's all the strategy its pea brain can hold.

Well, I was right about the final outcome.  At 16 steps search depth Bomb wants to play 18b hc5w mc4n mc5n rg7e, running away with our camel  for no gain.  That's all the deeper Bomb searched in 12 hours; with no capturing lines to guide it, Bomb can't prune as aggressively.

Bomb temporarily favored 18b hc5w mc4n mc5n hb5n at 15 steps depth, running away even more determinedly, and at 14 steps depth Bomb preferred 18b hc5w hg6e hh6w rg7e, which wastes two steps!  But buried next to this trash was a legitimately interesting move Bomb liked at 12 & 13 steps depth:

18b hc5w hg6e hh6w Rh5n

At first I thought this was easily refuted by 19w Ed5w mc4e Ec5s De2n, but after playing a few lines I'm not so sure.  Sometimes it seems to just end in a rabbit trade, but sometimes it seems we can capture the h5-rabbit without giving up our framed one.

In any case, I still prefer 18b hc5w hb5w ha5s mc4w, which seems to achieve the same goal of letting us go after h5-rabbit next turn, but with more options for us and fewer options for chessandgo.  Incidentally, when I fed my preferred move to Bomb, it considered it -0.99 for us, i.e. putting us behind by a rabbit positionally, which is bunk.  I think I've had my fun with Bomb for this move, and will make more progress with my unaided brain for the present.

Title: Re: Move 18
Post by RonWeasley on Dec 6th, 2007, 9:23am
Do we like 18b hc5w hb5w ha5s mc4w enough to approve it with a voice vote?  So far all commenting mobsters like this move with no competing alternatives.

Title: Re: Move 18
Post by Fritzlein on Dec 6th, 2007, 11:08am

on 12/06/07 at 09:23:08, RonWeasley wrote:
Do we like 18b hc5w hb5w ha5s mc4w enough to approve it with a voice vote?  So far all commenting mobsters like this move with no competing alternatives.

Strategic summary: Each side has an exposed rabbit, his on h5 and ours framed on c3.  We are menacing c3 so that chessandgo's elephant is forced to defend it.  We hope to thereby gain time to capture the h5 rabbit while our c3 rabbit remains merely framed.  Chessandgo has a variety of objectives.  If he can take our camel hostage, it may be worth it for him to give up his h5-rabbit in exchange.  If he can drive our camel over to the east, then our horse alone may not be enough of a threat to c3 to tie his elephant to defense.  Given enough time, his elephant can threaten something in f3, which could force our elephant to abandon the c3 rabbit.  Also chessandgo can complicate by advancing his g3-horse.

We could conceivably be forced to abandon our c3-rabbit without capturing his h5-rabbit.  Alternatively the race could end in a tie, with both sides having to give up their respective rabbits, in which case who is ahead or behind will be determined by other features of the resulting position.  I believe, however, that we are somewhat ahead in this race, and therefore we should not be happy with a tie.  Chessandgo will probably look for an opportunity to give up his rabbit for a threat that makes us abandon our rabbit, and he will be happy if he achieves that.

My main line currently looks like this:

18b hc5w hb5w ha5s mc4w
.    19w Ed5w Ec5w mb4e Eb5s
.    .    19b mc4n hg6e hh6w Rh5n

I am also concerned about the "strategic" move 19w Ed5w Ec5s Hg3n Hg4n, which doesn't directly threaten anything, but is calculated just to frustrate us.

Title: Re: Move 18
Post by 99of9 on Dec 6th, 2007, 3:52pm
What about a rabbit pull right now?
Something like
hg6e hh6w Rh5n hc5w
or
hg6e hh6w Rh5n mc4w

(I've only looked at the position for a few seconds, so do let me know the refutation if you've already found it.)

Title: Re: Move 18
Post by UruramTururam on Dec 6th, 2007, 5:03pm
Fine! I like when we have to start from scratch!

My first thought: 18b  hg6e hh6w Rh5n dd7s

Similar move to the ones proposed by 99of9 but with a different last step...

Title: Re: Move 18
Post by arimaa_master on Dec 7th, 2007, 3:54am

on 12/06/07 at 15:52:18, 99of9 wrote:
What about a rabbit pull right now?
Something like
hg6e hh6w Rh5n hc5w
or
hg6e hh6w Rh5n mc4w

(I've only looked at the position for a few seconds, so do let me know the refutation if you've already found it.)



That move ( 18b hc5w hg6e hh6w Rh5n) was mention by Fritzlein (this was bomb's suggestion at depth 12 and 13).

And explanation followed (see 3rd post above yours).


Title: Re: Move 18
Post by RonWeasley on Dec 7th, 2007, 6:53am
I couldn't find any obvious problem with doing the rabbit pull now.  However, I like doing it after the proposed hc5w hb5w ha5s mc4w because this separates our west side pieces from the h5 rabbit by an extra square and puts our camel-horse right on gold's horse-dog.  This makes our west threat better and the rabbit capture harder to defend.

Let's expect a vote Monday morning.

Title: Re: Move 18
Post by Soter on Dec 7th, 2007, 7:42am
Hi to everyone,


Quote:
Let's expect a vote Monday morning



So, we have the entire weekend to think, and we'll replenish our reserve - great!  I suppose it would be wise to deeply examine the consequences of  chessandgo's hypothetical response (Ed5s Ed4w mb5n Ec4w) to our hc5w hb5w ha5s mc4w. Don't get me wrong - I trust your intuition and experience very much;
I simply think the "ensuing mess" - as Fritzlein called it earlier in this thread - should become Jean's burden, not ours.

I'll try to help a bit on Saturday, but can't do it now - my planning window tends to misbehave and I'll have the chance to use a different computer tomorrow.

Title: Re: Move 18
Post by Soter on Dec 8th, 2007, 5:37am
A few half-baked ideas:

1.

18b hc5w hb5w ha5s mc4w
19w Ed5s Ed4w mb4n Ec4w
19b hg6e hh6w Rh5n rb8s

from here:

    1.1

    20w Hg3n Hg4n Hg5w De2n
    20b rb7s mb5e mc5e md5e

    1.2
   
    20w Hg3n Hg4n Hg5w Eb4e
    (here I have no idea - a dog flip with our horse?
     something else?)


2. (Fritzlein's main line)

18b hc5w hb5w ha5s mc4w
19w Ed5w Ec5w mb4e Eb5s
19b mc4n hg6e hh6w Rh5n

from here:

    2.1

    20w Hg3n Hg4n Hg5w Eb4e
    20b ha4n ha5e mc5e md5e

    2.2
   
    20w Hg3n Hg4n Hg5w Eb4n
    (doesn't look good IMHO)


3.

18b hc5w hb5w ha5s mc4w
19w Hg3n Hg4n Hg5w Ed5w
(slight advantage to us I think but may be wrong)

I must admit that after writing this I feel like a complete noob...

Title: Re: Move 18
Post by Fritzlein on Dec 9th, 2007, 5:03pm
Thanks for extending the tree, Soter.  I have added further to some of your lines.


on 12/08/07 at 05:37:13, Soter wrote:
18b hc5w hb5w ha5s mc4w
19w Ed5w Ec5w mb4e Eb5s
19b mc4n hg6e hh6w Rh5n
20w Hg3n Hg4n Hg5w Eb4n
    (doesn't look good IMHO)

I'm not sure if you mean that 20w doesn't look like a good move, or our position doesn't look good after 20w.  We could win material with 20b dd7s cc7s mc5e md5e.  Gold could get some compensation for lost material, but in all the lines I played forward we ended up clearly ahead.


Quote:
18b hc5w hb5w ha5s mc4w
19w Ed5s Ed4w mb4n Ec4w
19b hg6e hh6w Rh5n rb8s
20w Hg3n Hg4n Hg5w Eb4e
    (here I have no idea - a dog flip with our horse?
     something else?)

Yes, flipping the dog with 20b ha4e Da3n Da4n hb4w looks good for us.


Quote:
18b hc5w hb5w ha5s mc4w
19w Hg3n Hg4n Hg5w Ed5w
(slight advantage to us I think but may be wrong)

This actually seems hardest to refute, but maybe the positional answer of 19b mb4n ha4e Da3n mb5n retains our advantage.


Quote:
I must admit that after writing this I feel like a complete noob...

Actually your analysis is very useful.  It suggests that if chessandgo charges with his g3 horse, the exposed horse is too great a liability to him, which means he might not be able to complicate the position to his advantage.  Maybe he will just have to accept the capture of his rabbit after 18b hc5w hb5w ha5s mc4w.

Title: Re: Move 18
Post by Fritzlein on Dec 9th, 2007, 5:13pm

on 12/06/07 at 15:52:18, 99of9 wrote:
hg6e hh6w Rh5n mc4w

I'm not keen on winning a rabbit if we have to give up a camel hostage in the process.  It's true that the hostage would be less than ideal for Gold, but it would be compensation for the rabbit that we might not otherwise have to give.

Title: Re: Move 18
Post by Fritzlein on Dec 9th, 2007, 5:30pm

on 12/06/07 at 17:03:24, UruramTururam wrote:
My first thought: 18b  hg6e hh6w Rh5n dd7s

I am worried that in this line chessandgo can just let us take the threatened rabbit, while drumming up counterplay by flipping our horse.  Our camel would be lonelier in the west, and therefore more likely to be taken hostage, but Gold also can threaten the flipped horse in f3, possibly forcing us to abandon the c3 rabbit.

Title: Re: Move 18
Post by Fritzlein on Dec 9th, 2007, 5:45pm

on 12/06/07 at 07:09:21, arimaa_master wrote:
18b cc7s dd7w hc5w ce7w

This doesn't look bad for us, but appears to be a clear loss of time if chessandgo pushes our camel to d4.   We would have to try to rotate it back to the west, and meanwhile we're not even threatening his rabbit.

Title: Re: Move 18
Post by Fritzlein on Dec 9th, 2007, 5:59pm

on 12/06/07 at 15:52:18, 99of9 wrote:
What about a rabbit pull right now?
Something like
hg6e hh6w Rh5n hc5w

It seems that if chessandgo pushes our camel east with something like 19w Ed5w mc4e Ec5s De2n, he gets enough counterplay to let his rabbit be captured, since he can then force us to abandon the c3 rabbit.  I'm not sure about this, but we are clearly in worse shape than in the lines where we wait a turn to pull the h-rabbit.

Title: Re: Move 18
Post by Fritzlein on Dec 9th, 2007, 6:18pm
OK, playing a bit with the suggested moves makes me think this is an easy choice after all.  It appears that 18b hc5w hb5w ha5s mc4w is so strong that before long chessandgo will have to give up his h5-rabbit while ours remains merely framed, i.e. we are getting nearer to achieving our strategic objective of the last four moves.

The decision is easier because all the proposed alternatives allow chessandgo to at least gain time, if not force a rabbit trade to equalize outright.  We have to be patient for one more move, or we'll be throwing away our hard-won advantage.

Incidentally, after having analyzed both with and without Bomb on this move, I conclude that the bot's brain-dead suggestions were a waste of time.  If Bomb would have a function for us this move, it would be double-checking some of the sharp lines where chessandgo advances the g3-horse, but I expect Bomb would only confirm the conclusion that the advance is unsound.  I won't bother to do this check, as I would rather have a fellow human look at those lines anyway.

18b hc5w hb5w ha5s mc4w
.    19w Ed5w Ec5w mb4e Eb5s
.    .    19b mc4n hg6e hh6w Rh5n
.    .    .    20w Hg3n Hg4n Hg5w Eb4e
.    .    .    .    20b ha4n ha5e mc5e md5e (-+)
.    .    .    20w Hg3n Hg4n Hg5w Eb4n
.    .    .    .    20b dd7s cc7s mc5e md5e
.    .    .    .    .    21w Eb5e Ec5e me5s Ed5e
.    .    .    .    .    .    21b ed3e rc3x me4e Hf5n Hf6x mf4n
.    .    .    .    .    .    .    22w Ee5w Ed5e dd6s cc6x Rf1w
.    .    .    .    .    .    .    .    22b hg6s Rh6w Rg6w Rf6x hg5n
.    .    .    .    .    .    .    .    .    23w dd5w Ee5w dc5n dc6x Ed5w
.    .    .    .    .    .    .    .    .    .    23b mf5s mf4s mf3n Cf2n Cf3x (=+)
.    .    .    .    .    21w De2n Cf2n Cf3n Hf5e
.    .    .    .    .    .    21b cc6s me5e ce7s ce6s (-+)
.    19w Ed5s Ed4w mb5n Ec4w
.    .    19b hg6e hh6w Rh5n rb8s
.    .    .    20w Hg3n Hg4n Hg5w De2n
.    .    .    .    20b rb7s mb5e mc5e md5e
.    .    .    .    .    21w Cf2n Cf3n Hf5e Eb4e
.    .    .    .    .    .    21b hg6w Rh6w hf6s Rg6w Rf6x (-+)
.    .    .    20w Hg3n Hg4n Hg5w Eb4e
.    .    .    .    20b ha4e Da3n Da4n hb4w (=+)
.    19w Hg3n Hg4n Hg5w Ed5w
.    .    19b mb4n ha4e Da3n mb5n (=+)
18b cc7s dd7w hc5w ce7w
.    19w Ed5w mc4e Ec5s Hb3n
.    .    19b md4n md5w hb5w mc5w
.    .    .    20w Da3e Hb4w Ec4w Ra1n (=+)
18b hc5w hg6e hh6w Rh5n
.    19w Ed5w mc4e Ec5s De2n
.    .    19b md4e me4n me5n rh8s
.    .    .    20w Ec4e Ed4e Ee4n Da3s
.    .    .    .    20b hg6s Rh6w Rg6w Rf6x hg5n
.    .    .    .    .    21w Ee5w me6s me5s Ed5e (=)
.    .    19b hg6w Rh6w hf6s Rg6w Rf6x
.    .    .    20w md4e Ec4e Ed4n Ed5e (=)
18b hg6e hh6w Rh5n mc4w
.    19w Ed5s Ed4w mb4w Ec4w
.    .    19b hg6s Rh6w Rg6w Rf6x hg5n
.    .    .    20w rc3n Hb3e rc4e Hc3n (=)
18b hg6e hh6w Rh5n dd7s
.    19w Ed5s hc5e hd5e Ed4n
.    .    19b mc4w mb4e Hb3n rc3w
.    .    .    20w Ed5w mc4s Ec5s Ra1n (+=)
.    .    19b hg6s Rh6w Rg6w Rf6x hg5n
.    .    .    20w he5s Ed5e he4s Ee5s (+=)

Title: Re: Move 18
Post by RonWeasley on Dec 12th, 2007, 7:10am
Mob rule picks hc5w hb5w ha5s mc4w by a comfortable majority.  I got busy Tueday afternoon and didn't get the chance to stop the vote until Wednesday morning.  Somewhere in that time the number of votes went from 8 to 10, reinforcing my perception that some of the mobsters like to vote at the end of the election period.  These are not to be confused with lurkers who are on the voter list but do not vote.  I'll let the Department of Mysteries try to understand this.  I just count the votes.  Thanx to those who voted!

Title: Re: Move 18
Post by Fritzlein on Dec 12th, 2007, 9:08am
For the record:

    .    .    .    .    .    .    .    .    .    .    1. 2. 3. 4. 5.
1. hc5w hb5w ha5s mc4w (h->a4, m->b4)  .    .    .     -  7  7  7  8
2. hc5w hg6e hh6w Rh5n (h->b5, pull rabbit) .    .     3  -  3  6  5
3. hg6e hh6w Rh5n mc4w (m->b4, pull rabbit) .    .     3  2  -  6  4
4. hg6e hh6w Rh5n dd7s (d->d6, pull rabbit) .    .     3  2  2  -  5
5. cc7s dd7w hc5w ce7w (h->b5, shift small animals w)  2  3  4  3  -


This is indeed a comfortable majority, but with 3 dissenting votes I'm glad we decided with a formal election rather than with a voice vote.  I'm also glad that Mobsters are thinking for themselves and not taking my analysis tree as gospel.



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