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        Team Games >> 2009 One vs TheMob >> 2015 Move 4
        
(Message started by: harvestsnow on Aug 5th, 2015, 11:52pm)
Title: 2015 Move 4
Post by harvestsnow on Aug 5th, 2015, 11:52pm
Sharpvector played his (its?) move:
3s hh7s dd8s mg7s rh8s

http://arimaa.com/arimaa/notconv/old/boardimg.php?orient=n&size=300&imgtype=jpeg&ranks=rrr1rrr/r1cddc1r/1h4mh/4E/1H1e/3M/R1CDDCHR/RRR2RRR
Title: Re: 2015 Move 4
Post by SilverMitt on Aug 6th, 2015, 3:04pm
So, 2 moves into the game, 12 pieces are positioned symmetrically (rotationally).  The difference is in the positions of the camels, horses, and silver having a rabbit on e8 vs. a1.  This move will probably move horses and/or rabbits, with possibly a De3 step.
Title: Re: 2015 Move 4
Post by half_integer on Aug 6th, 2015, 6:37pm
I agree, at first look this seems like a good time to develop the home traps, on the b, e, and g files.

Is there any merit to Ee5nw de7s x though, to induce asymmetry in the opponent?
Title: Re: 2015 Move 4
Post by deep_blue on Aug 7th, 2015, 7:45am

on 08/06/15 at 18:37:15, half_integer wrote:
Is there any merit to Ee5nw de7s x though, to induce asymmetry in the opponent?

I don't really like that idea. We should not take the slightest disadvantage to induce asymmetry. (I don't know if this is a disadvantage but I thought so) Sure, we need some asymmetry to try to win the game, but so does Sharp.
But then I am not sure what a normal move would be. I guess Hg2n and maybe trying to proceed the attack against c6!? (not that I have any idea for a concrete move...)
Title: Re: 2015 Move 4
Post by Algorias on Aug 7th, 2015, 8:57am

on 08/06/15 at 18:37:15, half_integer wrote:
Is there any merit to Ee5nw de7s x though, to induce asymmetry in the opponent?


I'm not a strong early game player, but I don't see how this could lead to a disadvantage. In response Sharp either needs to shuffle and undo its d7 dog development (e.g. cf7s de6n cf6n dd7n), or allow one of its dogs to be flipped to the center. Intuitively it seems this line might leave sharp in a somewhat cramped position and/or net us some steps.

I would love it if a more experienced player could weigh in on this line in more detail.
Title: Re: 2015 Move 4
Post by ikalyoncu on Aug 7th, 2015, 11:24am
How about 4g  Hb4wnn Hg2n? The idea is that if silver takes 3 steps to to go west with its camel, then as the fourth step it can either play ra7e or hh6w. In the first case we can play 5g Ee5n Hg3nnn. In the second case we can pull a7 rabbit twice. I find both of these variations slightly good for gold and I don't see how silver can refute this plan. Please share your comments on this 4g, I would like to see your evaluation.
Title: Re: 2015 Move 4
Post by Hufflepup on Aug 7th, 2015, 2:51pm

Quote:
How about 4g  Hb4wnn Hg2n? The idea is that if silver takes 3 steps to to go west with its camel, then as the fourth step it can either play ra7e or hh6w. In the first case we can play 5g Ee5n Hg3nnn. In the second case we can pull a7 rabbit twice. I find both of these variations slightly good for gold and I don't see how silver can refute this plan. Please share your comments on this 4g, I would like to see your evaluation.


It isn't obvious to me that pulling silvers rabbits would improve our position. That advanced rabbit could easily cause us problems later.

This sort of move could easily lead to us getting into a race with opposing EMH/MH attacks if silver responded with something like ed4e ee4s hh6s hh5s. Maybe this isn't a problem if we want to get into this sort of situation - but it isn't obvious to me who would have the advantage.

Something like Md3e Me3e Mf3e X would lead to a stabler game if we thought a race would be to our disadvantage.

Alternatively Md3w Mc3w Hb4n Hb5w looks like it would lead to a slightly stronger attack in the west as our camel would be closer and silver would no longer be in a position to push it to the other wing.
Title: Re: 2015 Move 4
Post by ikalyoncu on Aug 7th, 2015, 6:19pm

on 08/07/15 at 14:51:59, Hufflepup wrote:
It isn't obvious to me that pulling silvers rabbits would improve our position. That advanced rabbit could easily cause us problems later.

This sort of move could easily lead to us getting into a race with opposing EMH/MH attacks if silver responded with something like ed4e ee4s hh6s hh5s. Maybe this isn't a problem if we want to get into this sort of situation - but it isn't obvious to me who would have the advantage.

Something like Md3e Me3e Mf3e X would lead to a stabler game if we thought a race would be to our disadvantage.

Alternatively Md3w Mc3w Hb4n Hb5w looks like it would lead to a slightly stronger attack in the west as our camel would be closer and silver would no longer be in a position to push it to the other wing.


About pulling the a7 rabbit, I presumed it is good for us on the basis that west is our strong wing (at least for the time being).

The outcome of the race you mentioned isn't clear to me as well. However, I feel that, we may be concerned with either
a) silver pushing our Camel east or
b) silver making an emh attack on the east
but not both, as they are quite contradictory.

Finally, if we decide to shift our Camel to the east wing, aiming a more stable game, then at least we shouldn't put it on g3 as it hinders the development of the Horse.
Title: Re: 2015 Move 4
Post by chessandgo on Aug 8th, 2015, 5:10am
ikalyoncu's 4g Hb4wnn Hg2n is the fast move. We can also take it slow, mix-and-matching development steps. Rh2n Rh1n have not been mentioned yet, I think they are legitimate candidates to prevents silver's horse from reaching h3. Hb4n alone is possible too, keeping the b-file closed for the hb6 can be tactically desirable when silver can handle our caMel in different ways. It also makes Hg2n marginally safer. De3n (in the way of the caMel though) and Hg2n have been mentioned. Rb1n and maybe Ra2n are not very sexy, but better than nothing presumably.

At first glance I like 4g Hb4n Rh2n Rh1n Hg2n best among slow moves. Silver could play 4s ra7s ra8s to deny us a6 though. If that is a problem, we can play 4g Hb4wnn Hg2n. Silver's horse cannot move to h3 on 4s (?), so if nothing drastic happens on 4s we can play Rh2n Rh1n on 5g.
Title: Re: 2015 Move 4
Post by chessandgo on Aug 8th, 2015, 5:11am

on 08/07/15 at 14:51:59, Hufflepup wrote:
Something like Md3e Me3e Mf3e X would lead to a stabler game if we thought a race would be to our disadvantage.

Alternatively Md3w Mc3w Hb4n Hb5w looks like it would lead to a slightly stronger attack in the west as our camel would be closer and silver would no longer be in a position to push it to the other wing.


Like for the previous move, if we are unable to decide whether going east or west is best with the caMel, then probably both are a loss of about a step when comparing to silver pushing our caMel either way.
Title: Re: 2015 Move 4
Post by chessandgo on Aug 8th, 2015, 5:42am

on 08/07/15 at 08:57:06, Algorias wrote:
I'm not a strong early game player, but I don't see how this could lead to a disadvantage. In response Sharp either needs to shuffle and undo its d7 dog development (e.g. cf7s de6n cf6n dd7n), or allow one of its dogs to be flipped to the center. Intuitively it seems this line might leave sharp in a somewhat cramped position and/or net us some steps.

I would love it if a more experienced player could weigh in on this line in more detail.


4g Ee5n Ee6w de7s loses 1 step for the pull and spends 2 steps to move the Elephant to d6, which is not a good square at the moment. Silver's plan is to attack down the g-file with the camel as soon as possible, and our Elephant will be needed to defend in the east. Thus moving 2 steps away from f3 should lose a total of 4 steps when we have to come back. The dd7 does not have to move away. Silver can lose only 3 steps to withdraw the de6, which is already bad for us, but since silver wants to be moving forward in the east, there are even better options for him. 5s mg5s is good enough for example. Leaving the dog on f6 too (re7s de6e for example).
Title: Re: 2015 Move 4
Post by half_integer on Aug 8th, 2015, 7:52pm

on 08/08/15 at 05:10:05, chessandgo wrote:
At first glance I like 4g Hb4n Rh2n Rh1n Hg2n best among slow moves. Silver could play 4s ra7s ra8s to deny us a6 though. If that is a problem, we can play 4g Hb4wnn Hg2n. Silver's horse cannot move to h3 on 4s (?), so if nothing drastic happens on 4s we can play Rh2n Rh1n on 5g.

I am liking the 4g Hb4wnn Hg2n for the reasons given above.  I don't see any real danger for the western horse.  However, I do think the c3 trap looks weakly defended and worry that something like hb6ss rb8s x could put us in a race where we don't have the advantage.  Depending on how the rest of you evaluate that possibility, my next choice would be home development moves such as the first one suggested above.

I am not in favor of any rabbit pulling; sharp has shown excellent ability to turn that into an asset for its own side.  Likewise, I agree with the logic that we shouldn't move our camel; let the opponent use steps if they want to force us to choose a side.
Title: Re: 2015 Move 4
Post by SilverMitt on Aug 8th, 2015, 9:29pm
In considering 4g Ha6 Hg3, I think it is important to evaluate the position after 4s Ed3:Me3 Hb4.  Though, in any case, I think I prefer just continuing the development rather than jumping to a6.
Title: Re: 2015 Move 4
Post by browni3141 on Aug 9th, 2015, 3:57am
I actually disagree that sharp will do well turning a pulled rabbit into an asset for itself. I think rabbit pulling is still one concept it struggles with, which would make it hard for lightvector to rely on it. I feel that the games I had the easiest time with against it were ones in which I pulled a rabbit.
However, I don't really want to rabbit pull unless it is an objectively good strategy, and that is not the case yet. I like Ha6 moves, but haven't done much thinking on it yet. I think it would likely be wrong to put it off much longer.
Title: Re: 2015 Move 4
Post by clyring on Aug 9th, 2015, 6:20am
Some thoughts on the specific proposals so far:


4g Ee5nw de7s z

Something like de7s loses two steps by default and I don't really even see what we seek to gain by it here. The silver dogs remain quite safe while the silver elephant remains in the center.


4g Hb4wnn Hg2n

Lots of comments on this one.

on 08/07/15 at 11:24:56, ikalyoncu wrote:
How about 4g  Hb4wnn Hg2n? The idea is that if silver takes 3 steps to to go west with its camel, then as the fourth step it can either play ra7e or hh6w. In the first case we can play 5g Ee5n Hg3nnn. In the second case we can pull a7 rabbit twice. I find both of these variations slightly good for gold and I don't see how silver can refute this plan. Please share your comments on this 4g, I would like to see your evaluation.

Silver almost certainly can't 'refute' our plan in the sense of directly punishing the horse advance, but with active silver play things will surely quickly become messy.


on 08/07/15 at 14:51:59, Hufflepup wrote:
It isn't obvious to me that pulling silvers rabbits would improve our position. That advanced rabbit could easily cause us problems later.

This sort of move could easily lead to us getting into a race with opposing EMH/MH attacks if silver responded with something like ed4e ee4s hh6s hh5s. Maybe this isn't a problem if we want to get into this sort of situation - but it isn't obvious to me who would have the advantage.

Although Ha6 could be used to pull rabbits, and our having the option pushes silver to play a sharper game, it is well-positioned for a future attack on c6 as well. If the silver elephant comes to e3, I expect dueling MH vs emh attacks to favor us slightly despite the one-step tempo disadvantage because the elephants are on silver's camel wing, making our job on defense easier.


on 08/08/15 at 05:10:05, chessandgo wrote:
If that is a problem, we can play 4g Hb4wnn Hg2n. Silver's horse cannot move to h3 on 4s (?), so if nothing drastic happens on 4s we can play Rh2n Rh1n on 5g.

I was previously thinking that something like 4g Hb4w Ha4n Ha5n Hg2n 4s hh6s hh5s hh4s dd7s 5g Md3e Me3e Hg3n Mf3e 5s ed4e ee4e Hg4n ef4e is at least not obviously unplayable for silver, but silver might have to just retreat the horse without achieving much with the time if we are less hasty about trying to punish the advance. More on this (and the rest of that post) later.


on 08/08/15 at 19:52:16, half_integer wrote:
I am liking the 4g Hb4wnn Hg2n for the reasons given above.  I don't see any real danger for the western horse.  However, I do think the c3 trap looks weakly defended and worry that something like hb6ss rb8s x could put us in a race where we don't have the advantage.

on 08/08/15 at 21:29:01, SilverMitt wrote:
In considering 4g Ha6 Hg3, I think it is important to evaluate the position after 4s Ed3:Me3 Hb4.  Though, in any case, I think I prefer just continuing the development rather than jumping to a6.

I looked at this kind of silver idea last move as well and my general conclusion has not changed: Our camel is much better able to involve itself in a fight breaking out on the western wing. I think we have a big advantage after either of these specific replies, and I don't see alternatives with the same aim with much promise to push me away from this 4g.


4g Hb4n Rh2n Rh1n Hg2n


on 08/08/15 at 05:10:05, chessandgo wrote:
We can also take it slow, mix-and-matching development steps. Rh2n Rh1n have not been mentioned yet, I think they are legitimate candidates to prevents silver's horse from reaching h3. Hb4n alone is possible too, keeping the b-file closed for the hb6 can be tactically desirable when silver can handle our caMel in different ways. It also makes Hg2n marginally safer. De3n (in the way of the caMel though) and Hg2n have been mentioned. Rb1n and maybe Ra2n are not very sexy, but better than nothing presumably.

At first glance I like 4g Hb4n Rh2n Rh1n Hg2n best among slow moves.

I don't much fear the hb6 advancing except possibly if we decide to pull a7 or something. Otherwise I'm not sure what you mean by the benefits of keeping our horse on the b-file. Feel free to elaborate.

I like advancing rabbit steps in the west, but I think we can't know which to play yet. If our camel is pushed east, then Rb1nn is the natural, efficient defending and developing move, but if we fight with our camel in the west, I think we would rather play Ra2nn(n)(n)(n)(n) down the road.


on 08/07/15 at 18:19:49, ikalyoncu wrote:
However, I feel that, we may be concerned with either
a) silver pushing our Camel east or
b) silver making an emh attack on the east
but not both, as they are quite contradictory.

Whether this is true depends on how you look at it. In any particular line, silver will play at most one of these options because pushing our camel east will more or less kill any silver attacking chances there normally. However, as long as silver retains both plans as reasonable options, we need to consider each plan and make sure that all of our steps are useful in either case.


on 08/08/15 at 05:11:52, chessandgo wrote:
Like for the previous move, if we are unable to decide whether going east or west is best with the caMel, then probably both are a loss of about a step when comparing to silver pushing our caMel either way.

I agree and would like to reiterate that moving our camel ourselves is a loss of at least one step in most cases until silver gives us a good enough reason to prefer one wing.
Title: Re: 2015 Move 4
Post by chessandgo on Aug 9th, 2015, 12:50pm
4g Hg2n Hb4n Hb5w Ha5n
4s Md3e ed4s hb6s hb5s
5g Me3n Me4w Ee5w Md4w
looks very good for us


on 08/08/15 at 19:52:16, half_integer wrote:
I am liking the 4g Hb4wnn Hg2n for the reasons given above.  I don't see any real danger for the western horse.  However, I do think the c3 trap looks weakly defended and worry that something like hb6ss rb8s x could put us in a race where we don't have the advantage.


Then our caMel moves to b3, H to b6 and our position is excellent?


on 08/09/15 at 06:20:03, clyring wrote:
4g Hb4n Rh2n Rh1n Hg2n

I don't much fear the hb6 advancing except possibly if we decide to pull a7 or something. Otherwise I'm not sure what you mean by the benefits of keeping our horse on the b-file. Feel free to elaborate.


Let's say
4g Hg2n Hb4n Hb5w Ha5n
4s Md3e ed4s hh6s dd7s
and we have to choose between relocating the caMel west with:
5g Me3n Ee5w Me4w Md4w
and give silver the opportunity to attack g3 quickly with our Elephant one step further, for example:
5s ed3n mg6s mg5s hh5s

Or defend b3 with small pieces, in which case silver's horse can jump into b3 at any time. It would presumably not work right away, since the position is fairly symetric except that our caMel is closer to the west than silver's, but it means we have to keep at least as many pieces "in the west" as silver at all times. Having our Horse on b5 instead of a6 might make our central pieces more flexible?
Title: Re: 2015 Move 4
Post by clyring on Aug 9th, 2015, 2:17pm

on 08/09/15 at 12:50:58, chessandgo wrote:
Let's say
4g Hg2n Hb4n Hb5w Ha5n
4s Md3e ed4s hh6s dd7s
and we have to choose between relocating the caMel west with:
5g Me3n Ee5w Me4w Md4w
and give silver the opportunity to attack g3 quickly with our Elephant one step further, for example:
5s ed3n mg6s mg5s hh5s

Or defend b3 with small pieces, in which case silver's horse can jump into b3 at any time. It would presumably not work right away, since the position is fairly symetric except that our caMel is closer to the west than silver's, but it means we have to keep at least as many pieces "in the west" as silver at all times. Having our Horse on b5 instead of a6 might make our central pieces more flexible?

Hmm, I considered this, but didn't think advancing pieces in the west was a problem for us.

on 08/09/15 at 06:20:03, clyring wrote:
I like advancing rabbit steps in the west, but I think we can't know which to play yet. If our camel is pushed east, then Rb1nn is the natural, efficient defending and developing move, (...)

As necessary we can play c2n c1n later for further defense. Our camel should probably not come west quickly in this line unless silver gives it a target to chase, though, and you might be right in that it is more costly for our camel to move east if we leave b3 open. (Incidentally, this would be less of a possible issue if we had Dc2 instead of Cc2.)
Title: Re: 2015 Move 4
Post by deep_blue on Aug 10th, 2015, 12:35am
So far for the voting I would give the following choices:
4g Hb4n Hb5w Ha5n Hg2n (Ha6 Hg3)
4g Hb4n Hg2n Rh2n Rh1n
4g Md3w Mc3w Hb4n Hb5w (Mb3 Ha5)

Any others you think would be important? Hufflepup, you mentioned Md3e Me3e Mf3e, what would be your 4th step there?

I plan to start the voting in about 24h but give it much time on this move (at least 2 days, depends on when I have internet connection) since the candidate moves seem clear and so those who aren't sure can keep discussing. ;)
Title: Re: 2015 Move 4
Post by Hufflepup on Aug 10th, 2015, 4:06pm

Quote:
Hufflepup, you mentioned Md3e Me3e Mf3e, what would be your 4th step there?


I prefer the plan to move the camel west to this move, so unless any one else wants to ropose a 4th step I wouldn't include it in the poll.


Quote:
Like for the previous move, if we are unable to decide whether going east or west is best with the caMel, then probably both are a loss of about a step when comparing to silver pushing our caMel either way.


This assumes silver will co-operate with our plan and pushes our camel where we want it to go.
Title: Re: 2015 Move 4
Post by clyring on Aug 10th, 2015, 5:02pm

on 08/08/15 at 05:11:52, chessandgo wrote:
Like for the previous move, if we are unable to decide whether going east or west is best with the caMel, then probably both are a loss of about a step when comparing to silver pushing our caMel either way.


on 08/10/15 at 16:06:33, Hufflepup wrote:
This assumes silver will co-operate with our plan and pushes our camel where we want it to go.

On the contrary, it explicitly assumes that  "...we are unable to decide whether going east or west is best with the caMel," ie that we believe moving the camel east or west are approximately equal in evaluation, and that we don't have the following:
[Just one wing that we would like our camel to occupy eventually, with the other not only infinitesimally inferior, but so much worse for us for silver to be able to justify spending steps moving it there on our behalf.]

If you or anyone else disagrees with that assumption, please feel free to voice such.
Title: Re: 2015 Move 4
Post by SilverMitt on Aug 10th, 2015, 5:16pm
It's unlikely that the silver elephant would push our camel to c3.  When it advances further, it would either plant itself on d3 and push the camel to e3, or come directly to e3 without pushing the camel.  In that sense, going west with our camel only commits us to the choice, but does not lose time (but we'd be behind by a step or two due to the initial setup).
Title: Re: 2015 Move 4
Post by half_integer on Aug 10th, 2015, 8:52pm
If the H->a6 H->g3 move is likely to be a favorite, I think it is worthwhile to try and determine the best reply and the refutation to it.  Anyone want to expand on what has already been said, and generate other replies?

edit: when I wrote that, my browser had not reloaded the page with the page 2 discussion.  chessandgo has already addressed the possibilities to some extent.  Keep analyzing and carry on.
Title: Re: 2015 Move 4
Post by deep_blue on Aug 15th, 2015, 9:54am
Detailed vote report:
Allowed voters: 23
Votes: 12 // :( hardly more than the half, I hope that trend doesn't go on...
Here's the link: http://civs.cs.cornell.edu/cgi-bin/results.pl?id=E_19c493146b7d57d4

1. 4g Hb4n Hb5w Ha5n Hg2n (Ha6 Hg3)
2. 4g Hb4n Hg2n Rh2n Rh1n
3. 4g Md3w Mc3w Hb4n Hb5w (Mb3 Ha5)
1.2.3.
1.--811
2.2--9
3.11--

Voting rights had:
Algorias, arimaa_master, aurelian, browni3141, chessandgo, clyring, CraggyCornmeal, DeathCure, deep_blue, half_integer, Harren, harvestsnow, Hufflepup, ikalyoncu, Knedlik, PerkofBR, phairland, RonWeasley, Samraku, SilverMitt, Skarn, supersamu, Therin8.


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