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        Team Games >> 2009 One vs TheMob >> 2015 Move 7
        
(Message started by: ikalyoncu on Oct 2^nd, 2015, 2:36am)

Title: 2015 Move 7
Post by ikalyoncu on Oct 2^nd, 2015, 2:36am

http://arimaa.com/arimaa/notconv/old/boardimg.php?orient=n&size=300&imgtype=jpeg&ranks=r1r1rr/rrc2cr/Hh1dd2r/5Em/R2e2Rh/1M4H/R1CDDC1R/1RR2RR

6s has played, swinging the rabbit from h3 to g4. I guess we can swing the camel from g5 to f4 on 7g, following chessandgo's suggestion on move 6 thread.

It is noteworthy that after 7g Ef5w mg5w mf5s Ee5e 7s ed4e Rg4n mf4e hh4n, we can play 8g Ef5s Rg1n Hg3e Hh3n and end up with a very good hostage, therefore we should expect hh4s step on 7s.

Title: Re: 2015 Move 7
Post by Hufflepup on Oct 2^nd, 2015, 3:08am

I've been looking at various possibilities for continuing the attack in the west and none of them look good. The problem is if we don't do something to the silver camel 7s could be something like: rh6s mg5n Rg4n X (X probably being an elephant move like ed4n). At which point silver is in a position to disrupt our attack, force our elephant to the west and capture our rabbit, and we aren't in a position to get any compensation.

I think we are going to have to generate some kind of threat in the east if the attack in the west is to get anywhere. Flipping the camel to f4 is a possibility. Alternatively something like Ra2n Ra4n Ef5w mg5w would allow us to make at least some progress with the attack, whilst simultaneously generating a threat around f3.

Title: Re: 2015 Move 7
Post by chessandgo on Oct 2^nd, 2015, 10:30am

on 10/02/15 at 02:36:52, ikalyoncu wrote:

It is noteworthy that after 7g Ef5w mg5w mf5s Ee5e 7s ed4e Rg4n mf4e hh4n, we can play 8g Ef5s Rg1n Hg3e Hh3n and end up with a very good hostage, therefore we should expect hh4s step on 7s.

The horse staying on h4 would be enough.

The scariest answer wrt silver's f3 attack would be:
7g Ef5w mg5w mf5s Ee5e
7s ed4e Rg4n mf4e ee4e
I think we'd have to race with our b-file attack:
8g Mb3n Mb4n Mb5s hb6s
8s Hg3w mg4s hh4w rb7s
9g Mb4s hb5s De2n Rg5e (without the last step there is a frame on f3), and it looks like we get there first after:
9s mg3s Cf2w mg2w hg4s
10g Ef5e Eg5s hg3e Eg4s

Lots of other things for silver to try of course.

I'm not sure what the best 4th step would be for silver if it keeps its elephant centered on 7s, nothing looks very appealing, maybe de6e? At worst we would be in an ok defensive position with 8g Rg5e Ef5e x x and ready with the b-file attack on the next turn?

Title: Re: 2015 Move 7
Post by browni3141 on Oct 2^nd, 2015, 11:50am

What is the reason for the camel flip?
7g Ef5w mg5w mf5s Ee5e
7s ed4e Rg4n mf4e ee4w
Has silver not gained something for nothing here?

Title: Re: 2015 Move 7
Post by SilverMitt on Oct 2^nd, 2015, 2:45pm

I'm inclined to prefer Ed4 to Ef4 as the 4th step if we flip the camel, although I'm not sure I'd play either. I'm most curious about the Hh5 step (I'm not convinced of a good hostage after 8g g2 Hh4 Ef4 8s H:Rf5/g6 M:Hh3).

Title: Re: 2015 Move 7
Post by arimaa_master on Oct 2^nd, 2015, 7:34pm

on 10/02/15 at 11:50:49, browni3141 wrote:

What is the reason for the camel flip?
7g Ef5w mg5w mf5s Ee5e
7s ed4e Rg4n mf4e ee4w
Has silver not gained something for nothing here?

Those were my thought exactly too. At first glance I would play something like this 7g Rh2n Rg1n Rg2e Ra1n (few seconds later I see that silver can answer with rh6s mg5n Rg4n ..., which doesn´t seem good for us, so for now I don´t have a good 7g candidate).

Title: Re: 2015 Move 7
Post by chessandgo on Oct 3^rd, 2015, 3:33am

How about
7g Ef5w mg5w mf5s Ee5e
7s ed4e Rg4n mf4e ee4w
8g Rg5e Ef5e Mb3n Ra4n or 8g Ef5s Ef4n mg4w Mb3n?
It seems to me we have decent chances to get that hb6 pull.

Title: Re: 2015 Move 7
Post by Hufflepup on Oct 5^th, 2015, 7:02am

We have been using up some of our reserve in the last few moves. This is a little bit concerning as we haven't been in a particularly complicated position yet. Can we try and start the poll in time for the move to be made before we have to dip into the reserve, and save it for when we really need it?

As for the move we should play, I agree with chessandgo. The camel flip looks good and I can't see any other alternative that is likely to get us anywhere.

Title: Re: 2015 Move 7
Post by deep_blue on Oct 5^th, 2015, 7:39am

So far considered moves:
7g Ef5w mg5w mf5s Ee5e

To be noted: We haven't considered any alternatives so far. Please try to find some, since otherwise we can't compare the camel flip lines to any other.

If we still have only one move tomorrow evening (as usual "UTC evening") I will play the move without poll.

Title: Re: 2015 Move 7
Post by lucifugero on Oct 5^th, 2015, 11:39am

i don't know if this could be considered:

7g De2n Ef5w Ee5e de6s

any thoughts on that?

Title: Re: 2015 Move 7
Post by Hufflepup on Oct 5^th, 2015, 12:04pm

Quote:

7g De2n Ef5w Ee5e de6s

Silver could undo the dog pull easily with something like 7s: dd5s de5n dd5n X, so this wouldn't get us anywhere.

Title: Re: 2015 Move 7
Post by SilverMitt on Oct 5^th, 2015, 2:53pm

It seems that we should be fine with a rabbit sacrifice, in general, and the question is whether we could make progress in the west if it becomes EMH vs. EH, while silver works on capturing the rabbit before continuing the counterattack in the southeast. I think we wind up behind in that sort of race.

Meanwhile, while silver could arguably be said to gain time after the camel flip, at least the camel will be more vulnerable on g4, and silver will eventually either have to retreat it or involve the elephant to keep it safe. Our own rabbit is now rather in our way on the 4th rank and, while in more danger on the 5th, can also get in silver's way or require several steps to capture.

I am still interested in the analysis after 7g E::Mf4 7s Ee4 M:Rg5 Hh5. After, say, 8g Ef4 g2 Hh4 8s H:Rg6 M:Hh3, would we be trying for a camel hostage with something like 9g Hg3 E:Mh3?

Title: Re: 2015 Move 7
Post by Heyckie on Oct 5^th, 2015, 4:26pm

Some other candidates I can't immediately rule out:

7g Rg4w Rf4w Ra2n Rb1n
7g mg5e Ef5e Ra2n Rb1n
7g Rg4w Rf4w Ef5w mg5w
7g Ef5w mg5w Ra2n Rb1n
7g Ef5w mg5w Ra4n Mb3n
7g Rg4w Rf4w Ra4n Mb3n
7g Mb3n Mb4n Mb5w hb6s.

Better players probably can find a clear refutation to some of those. I don't like advancing eastern rabbits here.

Title: Re: 2015 Move 7
Post by browni3141 on Oct 6^th, 2015, 1:13am

Perhaps it will be easier to discuss if we have some ideas to anchor on.

We probably shouldn't allow silver to get hg2 cheaply, so any quiet move should probably have either g1n or h2n.

The main idea of our opening so far was to delay silver attacking plans in the east while setting up a counter-attack in the west. It feels like a good time to advance that counter-attack as the east isn't critical or even moderately dangerous right now.

Based on this a move like 7g g1n b3nn a4n seems pretty good in principle.

Other attacking moves are potentially good in principle as well, such as 7g b3nnw b6s, but this should be searched deeper as things could get a little messy.

Silver's main counter-strategy to our western development is to threaten our g4 rabbit while seeking opportunities to advance the attack in the east, such as hg2.

Edit:

Silver's most concerning reply for me to 7g b3nnw b6s is hg2, but this line seems fairly forcing in response.

7g Mb3n Mb4n Mb5w hb6s
7s hh4s Rh2s hh3s hh2w
8g Ef5s Ef4s Hg3e Ef3e
8s ed4n ed5w ec5n ec6w
9g Eg3w hg2n Ef3n hg3w hf3x
9s eb6e Ha6e ec6s Hb6e Hc6x
10g Rg4e Ef4n mg5s Ef5e
10s hb5n ec5w eb5s Ma5e
11g mg4w Eg5s mf4s mf3x Eg4w
11s Mb5e eb4n Mc5n Mc6x eb5e
12g Ef4w Ee4n de6n Ee5n

Gold has a good position because f6 is relatively weak and he has more advanced rabbits on a depleted board. c3 is also weak, but silver will have a hard time exploiting it efficiently because gold has the initiative. The only way to get a quick attack would be to use the horse, and we can reply by returning with the elephant to take a hostage which we seem well set-up for.

Other 7s replies are less forcing, but also need some analyzing, and I may well have missed something is the line given.

7s rh6s mg5n Rg4n ed4w for example.

Title: Re: 2015 Move 7
Post by SilverMitt on Oct 6^th, 2015, 1:35am

Well, as I'd rather not play for a camel hostage, I am inclined to favor a move like 7g g2 a5 Mb5. What would happen after a reply like 7s h5 Mg6:R Ec4, or what should we expect as 7s then?

Title: Re: 2015 Move 7
Post by browni3141 on Oct 6^th, 2015, 1:48am

on 10/06/15 at 01:35:48, SilverMitt wrote:

Well, as I'd rather not play for a camel hostage, I am inclined to favor a move like 7g g2 a5 Mb5. What would happen after a reply like 7s h5 Mg6:R Ec4, or what should we expect as 7s then?

8g Mb5e hb6s Ha6e Ef5w
Unless there is a tactical refutation, I believe we have sufficient compensation for the soon to be lost rabbit. The position seems close.

If we advance in the west, we may be almost forced to move our elephant back west as well, which seems like a loss of time, but our elephant has already served a purpose in the east by restraining silver's play there, which it can't do effectively anymore until silver has attacking prospects again. It should be okay.

Title: Re: 2015 Move 7
Post by chessandgo on Oct 6^th, 2015, 9:43am

on 10/05/15 at 14:53:04, SilverMitt wrote:

I am still interested in the analysis after 7g E::Mf4 7s Ee4 M:Rg5 Hh5. After, say, 8g Ef4 g2 Hh4 8s H:Rg6 M:Hh3, would we be trying for a camel hostage with something like 9g Hg3 E:Mh3?

aren't all the b-file moves at least as effective on 8g in this variation as on 7g?

Fwiw I wouldn't be thrilled about losing a Rabbit for a Hb6.

Title: Re: 2015 Move 7
Post by Hippo on Oct 6^th, 2015, 12:46pm

on 10/02/15 at 10:30:49, chessandgo wrote:

Just a little note ...
7g Ef5w mg5w mf5s Ee5e
7s ed4e Rg4n mf4e ee4e
8g Mb3n Mb4n Mb5s hb6s
8s Hg3w mg4s hh4w rb7s
9g De2n Dd2e Mb4s hb5s seems to be an alternative to Rh5

Title: Re: 2015 Move 7
Post by SilverMitt on Oct 6^th, 2015, 4:46pm

I'm pretty sure silver wouldn't go for the MH trade after 7g Ma5:H (also, it might be helpful to describe in words what is happening in the lines we give). Rather, it seems we would be giving up a rabbit for an at-best unclear position afterwards, and our elephant can forget about threatening the silver camel.

I am still curious about how silver would reply to 7g a5 Mb5 g2(/h3?). This sort of move seems to be keeping our options open, and if silver can't safely pull the rabbit to g5, it is worth considering.

Otherwise, I think the camel flip with 7g E::Mf4 will allow us to keep the silver camel vulnerable. The possibility with the iffy camel hostage for a rabbit is unclear to me, but we are well set up to attack c6, so perhaps even a fairly dubious-seeming hostage may be effective. Meanwhile, if silver allows us to move our rabbit to h5, it should be relatively safe for a while, while silver would need to spend several steps to secure its camel (and horse?) before its elephant could return to help defend c6.

Title: Re: 2015 Move 7
Post by deep_blue on Oct 6^th, 2015, 6:06pm

Okay, since we DO have some discussion on alternatives now I'll let it going for another day. (or half a day; I'll decide the details on that tomorrow)

Title: Re: 2015 Move 7
Post by browni3141 on Oct 7^th, 2015, 1:17am

on 10/06/15 at 16:46:31, SilverMitt wrote:

I am still curious about how silver would reply to 7g a5 Mb5 g2(/h3?). This sort of move seems to be keeping our options open, and if silver can't safely pull the rabbit to g5, it is worth considering.

I think silver would pull the rabbit to g5, and can do so "safely," but it's still worth considering.

I don't think we should concern ourselves too much with this rabbit. Opening rabbits aren't worth a lot and by trying too hard to defend an endangered opening rabbit we could lose more positionally and end up losing the rabbit in the long run anyway. The only desirable outcome for the rabbit I think would be landing it on h5 where it is safe short term and provides some value.

The camel flip seems okay, but if this were my own postal I'd probably spend at least an hour evaluating the "scary" 8s branch chessandgo posted.

Title: Re: 2015 Move 7
Post by SilverMitt on Oct 7^th, 2015, 2:11am

Ah, I've finally looked at that sample line. I do think the fundamentals are on our side if that's the line silver chooses, as we have the elephants both in the east. I don't see how silver could dream of gaining an advantage there without a line where the silver elephant has time to go west.

Title: Re: 2015 Move 7
Post by Hufflepup on Oct 7^th, 2015, 3:39am

Quote:

Silver could reply with
7s: rh5s mg5n Rg4n Ed4n

If we continue the attack with
8g Mb5e hb6s Ha6e Ef5w
8s ed5w Mc5s Ra5s hb5w
9g Ee5w dd6n Ed5n Dd2n
9s Capture the rabbit
10g Dd3n Mc4w Mb4s Mb3w
10s hb6n hh4s mg6e rg5n
11g Ra4e Ma3n Ma4n rb4n
11s rg6w mh6w (capture rabbit) mg6s rh5s
12g Ma5s ha6s Ma4s ha5s
12s mg5s Hg3n mg4w hh2w
13g Ma3e ha4s De2n Dd4n

This would probably lead to a horse exchange followed by opposing deadlocked traps. We would be down a rabbit though without any clear tactical advantage to show for it.

Title: Re: 2015 Move 7
Post by deep_blue on Oct 7^th, 2015, 9:59am

If we were to play Mb5 Ra5 and e.g. Rh3, what would we do on 7s eb5 Mc5? If we play 8g Ed6 on that silver might just push the camel back to c4 and continue in the east e.g. by pulling g4. I don't see how we get our west attack going then.
Alternatively if we play 8g Ed5 and camel back I don't see great attacking prospects for us either.
And if we flip mf4 silver has the choice of trading only camels, after which i am not sure if our Ha6 is that good anymore, or he delays the capture with hg4 me5 and it's not clear to me again how we proceed.
So what is the plan there?

P.S. Considered moves:
7g Ef5w mg5w mf5s Ee5e
7g Mb3n Mb4n Ra4n Rg1n
7g Mb3n Mb4n Ra4n Rh2n
7g Mb3n Mb4n Mb5w hb6s

Title: Re: 2015 Move 7
Post by chessandgo on Oct 7^th, 2015, 1:44pm

on 10/07/15 at 09:59:40, deep_blue wrote:

If we were to play Mb5 Ra5 and e.g. Rh3, what would we do on 7s eb5 Mc5?
7g Mb3n Mb4n Mb5w hb6s

That's a good point, it looks like we'd be in a bad shape.

Title: Re: 2015 Move 7
Post by Hufflepup on Oct 7^th, 2015, 1:58pm

Quote:

And if we flip mf4 silver has the choice of trading only camels, after which i am not sure if our Ha6 is that good anymore, or he delays the capture with hg4 me5 and it's not clear to me again how we proceed.

if silver replied with hg4 me5 we coul play 8g: Ef5s Rg1n Rh2n Rh3n .
Silver is then forced to commit the elephant to f3 for a time to save the horse. Even then we would still be in a position to frame the horse on 9g leaving us free to proceed with the western attack.

Alternatively we could play 8g me5s Ef5w me4s Ee5s which would leave silvers camel in a highly vulnerable position.

I don't think silver can force a camel exchange as long as we don't advance too quickly in the west.

Title: Re: 2015 Move 7
Post by deep_blue on Oct 7^th, 2015, 2:18pm

on 10/07/15 at 13:58:08, Hufflepup wrote:

That comment above from me was meaning camel flip AFTER 7g Mb3n Mb4n Ra4n X 7s ed4w ec4w Mb5e eb4n after which it is not good. If it is good in the board position I don't know, but then, it doesn't look as if we have a whole lot of alternatives...

Title: Re: 2015 Move 7
Post by browni3141 on Oct 7^th, 2015, 4:52pm

on 10/07/15 at 09:59:40, deep_blue wrote:

If the move is refuted it would be nice to have some with a similar idea on the poll so that the idea doesn't die entirely, like any substitution of Mb4n for a different fourth step.

I already considered this reply, but didn't think much of it. Maybe there's something to it, but I don't see how we're in bad shape.

Silver loses time with this camel push maneuver by moving the elephant west and back east, and gold loses time because our camel needs to be unfrozen and the elephant needs to go west (which it would have done anyway in a lot of lines)

7g Mb3n Mb4n Ra4n Rg1n
7s ed4w ec4w Mb5e eb4n
8g Ef5w Ee5w dd6n Ed5n
8s Mc5s eb5e mg5e Rg4n
9g Cc2n Rc1n Mc4w Dd2n

I feel comfortable with our position. If silver then captures we have the pull and replace or the dog south push.

Or
8s Mc5e eb5e Md5e ec5e
9g de6e Ed6e Me5s Dd2n or whatever.

If silver spends time to push us around we are justified in spending time to maneuver.

Title: Re: 2015 Move 7
Post by Heyckie on Oct 7^th, 2015, 7:32pm

on 10/07/15 at 16:52:11, browni3141 wrote:

any substitution of Mb4n for a different fourth step.

7g Mb3n Ra4n Ra2n Rg1n?

Title: Re: 2015 Move 7
Post by deep_blue on Oct 8^th, 2015, 5:43am

on 10/07/15 at 16:52:11, browni3141 wrote:

7g Mb3n Mb4n Ra4n Rg1n
7s ed4w ec4w Mb5e eb4n
8g Ef5w Ee5w dd6n Ed5n
8s Mc5s eb5e mg5e Rg4n
9g Cc2n Rc1n Mc4w Dd2n

I feel comfortable with our position. If silver then captures we have the pull and replace or the dog south push.

Or
8s Mc5e eb5e Md5e ec5e
9g de6e Ed6e Me5s Dd2n or whatever.

If silver spends time to push us around we are justified in spending time to maneuver.

I see your point, and even though I am not so sure about it I agree that we have compensation. But what if silver doesn't push us around any more than on 7s? Say, 8s m::Rg6 (or however that notation works :P) then sure, silver e is a bit decentralized but I also don't see how we immediately profit from it. e.g. 9g Dd2nnn Mc5n 9s Rf6x eb5e Ra5e and silver got plenty of time to start the counter attack against f3. And any other gold move doesn't really threaten to take over c6...

Title: Re: 2015 Move 7
Post by browni3141 on Oct 8^th, 2015, 1:32pm

on 10/08/15 at 05:43:51, deep_blue wrote:

I don't like that 8s, but silver could pull once and stuff the c6 trap which is solid.

8g Ef5w Ee5w de6s Mc5s
8s eb5e mg5n Rg4n rh6s
9g Cc2n Rc1n Mc4w Ra2n

seems better for gold. Silver's elephant decentralization is punished.

I'm torn between this move and pulling the horse to b5 with Ma5.

Or my suggestion that came after the poll started which was too late to add, I guess.

Title: Re: 2015 Move 7
Post by SilverMitt on Oct 8^th, 2015, 2:34pm

I think it goes to evaluation philosophy. I am rather fundamentally opposed to an attack around c6 that is EMH vs. EH, involves giving up a rabbit, and is susceptible to a swift MH counter around f3.

I do not mind advancing in a way that will keep silver from forcing our elephant west, which essentially means keeping our own camel secure for the time being. But I don't see a move that meets these criteria while creating enough compensation for the weak rabbit.

Meanwhile, flipping the camel seems a fairly natural move that works towards many of our goals. Anyway, I can accept browni's suggestions, as well, if chosen.

Title: Re: 2015 Move 7
Post by deep_blue on Oct 10^th, 2015, 5:09am

Detailed vote report:
Allowed voters: 25
Actual votes cast: 9
Link to poll result: http://civs.cs.cornell.edu/cgi-bin/results.pl?id=E_1e9ae9dd88643ff9

1. 7g Ef5w mg5w mf5s Ee5e (E::mf4)
2. 7g Mb3n Mb4n Mb5w hb6s (Ma5:h)
3. 7g Ef5w mg5w Ra4n Mb3n (Ee5:m Ra5 Mb4)
4. 7g mg5e Ef5e Ra2n Rb1n (E:mh5 Ra3 Rb2)
tied 5. 7g Mb3n Mb4n Ra4n Rg1n (Mb5 Ra5 Rg2)
tied 5. 7g Mb3n Mb4n Ra4n Rh2n (Mb5 Ra5 Rh3)
7. 7g Ef5w mg5w Ra2n Rb1n (Ee5:m Ra3 Rb2)
8. 7g Rg4w Rf4w Ef5w mg5w (Re4 Ee5:m)
9. 7g Rg4w Rf4w Ra4n Mb3n (Re4 Ra5 Mb4)
10. 7g Rg4w Rf4w Ra2n Rb1n (Re4 Ra3 Rb2)

	1.	2.	3.	4.	5.	6.	7.	8.	9.	10.
1.	-	6	8	7	8	8	8	8	8	9
2.	2	-	5	6	8	7	6	7	7	7
3.	1	3	-	4	5	6	6	5	6	7
4.	1	2	3	-	4	5	5	6	6	7
5.	1	1	3	3	-	3	4	5	5	5
6	1	1	2	3	3	-	4	6	5	5
7	1	3	2	3	4	3	-	4	4	5
8.	1	2	3	2	2	2	3	-	3	4
9.	1	2	2	2	3	2	1	2	-	3
10.	0	2	1	1	3	2	0	1	0	-

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

Title: Re: 2015 Move 7
Post by Hippo on Oct 17^th, 2015, 3:52am

Again I voted just once.

Title: Re: 2015 Move 7
Post by deep_blue on Oct 17^th, 2015, 6:28am

on 10/17/15 at 03:52:16, Hippo wrote:

Again I voted just once.

What do you mean? Have I lost you on my mailing list? Or did you simply not have the time to vote but could have? (in which case that's okay, I only name who could have voted not if they actually did, since thats otherwise hard to find out)

Title: Re: 2015 Move 7
Post by chessandgo on Oct 18^th, 2015, 3:09am

on 10/06/15 at 12:46:10, Hippo wrote:

Just a little note ...
7g Ef5w mg5w mf5s Ee5e
7s ed4e Rg4n mf4e ee4e
8g Mb3n Mb4n Mb5s hb6s
8s Hg3w mg4s hh4w rb7s
9g De2n Dd2e Mb4s hb5s seems to be an alternative to Rh5

Oh, you're right (I forgot to asnwer that one).

Title: Re: 2015 Move 7
Post by Hippo on Oct 29^th, 2015, 8:47am

on 10/17/15 at 06:28:08, deep_blue wrote:

I am twice in the wiki page and on all these announcements ...who is approved to vote ... seems originally you want to make the list alphabetically sorted than you resign on it ... leaving me as a mark of the changed decision ;)