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        Arimaa >> General Discussion >> Looking for tips on strategy
        
(Message started by: Swynndla on Mar 6^th, 2006, 3:57am)

Title: Looking for tips on strategy
Post by Swynndla on Mar 6^th, 2006, 3:57am

Hi I'm new to Arimaa, and even though I've had lots of problems playing online (shockwave on both linux pc's crashes all my different browsers, especially when I'm about to win ;) ... the only way I can play is to connected to a windows Citrix server that I don't admin, and play from there ... but in the mean time my rating kept going down to a low of 1024), I'm finding this game very addictive! :)

Question: I'm now keen at looking for strategy tutorials (rather than ones on tactics) to read up on ... any advice besides what I've found? I've found:

http://arimaa.com/arimaa/twiki/bin/view/Arimaa/ArimaaStrategy
http://arimaa.com/arimaa/twiki/bin/view/Arimaa/FritzleinVsOmar2005PostalChampionship

I found the second one extremely good, and Fritzlein's post-games thoughts even better.

I know I should learn tactics first, but that's (to me) boring ;) ... I'm hoping the tactics will sort themselves out.

Title: Re: Looking for tips on strategy
Post by Ryan_Cable on Mar 6^th, 2006, 4:41am

Wikipedia has several good articles on Arimaa:
http://en.wikipedia.org/wiki/Arimaa_tactics
http://en.wikipedia.org/wiki/Arimaa_strategy

There is also a Wikibook, but it is not as polished and may be confusing if you are not already familiar with basic strategy:
http://en.wikibooks.org/wiki/Arimaa

I guess you have already seen the BotSlayer page. It has descriptions of basic anti-bot strategies with example games:
http://arimaa.com/arimaa/twiki/bin/view/Arimaa/BotSlayer

You can also learn a lot by looking at top human games in the archives. The 2006 World Championship provides a nice collection of such games:
http://arimaa.com/arimaa/wc/2006/showGames.cgi

However, the key to getting your rating back up to ~1500 is mostly simple stuff: learn about and make use of mutual protection, always check all 4 traps before you send your move, don't advance non-elephant pieces in the center without a good reason.

Title: Re: Looking for tips on strategy
Post by Swynndla on Mar 6^th, 2006, 3:23pm

Ahhhh thanks for that, I'll be sure to look at those links.

On the citrix windows server that I don't admin, using the IE browser isn't that good either, as every time I move, it hangs for a minute and I lose a minute each time I move. I installed firefox to my "Documents and Settings" folder which I have access to, and firefox (for windows) works very nicely. Now I should be able to start concentrating on playing some games.

Title: Re: Looking for tips on strategy
Post by RonWeasley on Mar 7^th, 2006, 7:28am

Some of us who use Firefox experience frequent browser crashes beginning at around move 20. You can still get back into the game after you get back into the gameroom by clicking on your name next to your game icon. You lose about 30 seconds each time. It takes a while to get used to this and keeps me personally from playing harder opponents and fast time controls. If this happens to you and you lose you may elect to unrate your game.

Title: Re: Looking for tips on strategy
Post by Fritzlein on Mar 7^th, 2006, 8:14am

on 03/06/06 at 03:57:25, Swynndla wrote:

I'm finding this game very addictive! :)

Join the club. I like to play Arimaa so much, it undermines every other project I undertake.

Quote:

Question: I'm now keen at looking for strategy tutorials (rather than ones on tactics) to read up on ... any advice besides what I've found? I've found:

http://arimaa.com/arimaa/twiki/bin/view/Arimaa/ArimaaStrategy
http://arimaa.com/arimaa/twiki/bin/view/Arimaa/FritzleinVsOmar2005PostalChampionship

I found the second one extremely good, and Fritzlein's post-games thoughts even better.

Flattery will get you everywhere with me. I've extended the comments at http://arimaa.com/arimaa/twiki/bin/view/Arimaa/FritzleinVsOmar2005PostalChampionship to move 42. It was a useful for exercise for me to review this game again, because I understand some of Omar's moves much better now than I did at the time. Back then I had no clue what he was up to, and was continually amazed that the game stayed balanced despite all the "bad" moves he was making. :P

I believe (or at least hope!) my strategic understanding has matured somewhat in the intervening year, so my new commentary may contain some insights missing from my original post-game comments. Even so, there is so much I don't yet comprehend about the game, I'm sure that another year from now I'll look back on my current commentary as rubbish.

Title: Re: Looking for tips on strategy
Post by Swynndla on Mar 7^th, 2006, 3:13pm

Well done! I'm learning a lot through that commentary ... I've found that annotated games in chess have help me a lot with understanding long term themes and strategies, so it's great to see this is starting to happen in arimaa :)

Title: Re: Looking for tips on strategy
Post by Miki on Mar 7^th, 2006, 3:25pm

Agreed, I read over a lot of that stuff after it was linked. I wish there were more annotated games put there, that would be a very good way to understand what's going on sometimes.

Title: Re: Looking for tips on strategy
Post by Swynndla on Mar 7^th, 2006, 4:18pm

http://en.wikipedia.org/wiki/Arimaa says:

Code:

As David Fotland said, "For a while my program was as strong as or stronger than any person, but the human players improved rapidly and developed some new strategic concepts that were very difficult to capture in a computer program."

I know that there are several strategies that bot's don't handle all that well (http://arimaa.com/arimaa/twiki/bin/view/Arimaa/BotSlayer), but I'm wondering what strategies David Fotland was refering to specifically?

Title: Re: Looking for tips on strategy
Post by Fritzlein on Mar 7^th, 2006, 5:48pm

on 03/07/06 at 16:18:01, Swynndla wrote:

As far as I know, at the time David said that the only anti-bot strategies were camel hostage, elephant blockade, and rabbit-pulling. All the E-H attack variations came later.

Title: Re: Looking for tips on strategy
Post by Fritzlein on Mar 8^th, 2006, 5:11pm

OK, now I have added commentary through the end. Swynndla, thanks for fixing the typos. Everyone else should feel free to fix mistakes as well, or better still, insert additional commentary. It would be great to have different interpretations of various moves, and to hash it out until the language reflects the consensus view on strategy rather than just my opinion. If you are too shy to challenge my pronouncements from on high, then at least ask questions about why an alternative interpreation wouldn't be valid. Obviously I didn't understand the game very well while it was happening, and I hardly believe I totally get it now either, so contradictory commentary is very desirable. TIA.

Title: Re: Looking for tips on strategy
Post by Swynndla on Mar 11^th, 2006, 6:47pm

I've been trying to look at it for the last couple of days, but all I get it dots and lines ... there must be a twiki problem?

Title: Re: Looking for tips on strategy
Post by nbarriga on Mar 11^th, 2006, 7:02pm

I'm having trouble with the Twiki this last 2 days also. The information seems to be downloaded, but my browser doesn't display it.

Title: Re: Looking for tips on strategy
Post by Fritzlein on Mar 12^th, 2006, 1:16am

I also can't get the BotBashers page, or other pages in the local Wiki.

Title: Re: Looking for tips on strategy
Post by Swynndla on Mar 20^th, 2006, 7:48pm

Now that twiki is up again, I went through the commented game:
http://arimaa.com/arimaa/twiki/bin/view/Arimaa/FritzleinVsOmar2005PostalChampionship

I can understand some of it better now that I've played a few games, but I'm still impressed by the level of depth that you have shared! I learned heaps, thank you for annotating this game Fritzl :)

I have a few questions if I may, and I have also suggested fixes for possible typos (although I'm not sure about the east-west ones, as sometimes you refer to the east wing as Silver's west wing, and this is a bit confusing for me). I didn't think you'd mind, Fritzlein, if I pointed these things out (along with my questions) in this forum rather than emailing you, so I hope I wont offend you.

Here goes:

5w: "Current opening theory suggests that it is bad to give up a horse hostage on a wing where the opposing game waits," ... do you mean the opposing camel waits?

5b: "A plausible alternative attack would have been to push Omar's e3 horse to d3, unbalancing Omar's forces by putting both horses on the same wing, but that wouldn't be to Omar's disadvantage unless Fritzlein switched wings with his camel as well." ... (italics mine) not clear ... do you mean that if both camels were on the opposite wing, then Gold's east wing would be weaker, and vulnerable to such things as a E-H attack (whereas with the camel waiting, the east side isn't weak for Gold, as the camel is there to defend ... and Silver's camel cannot increase the pressure on the east wing while Gold's elephant is there, or it'll be in danger of being taken hostage)?

8b: "Had Fritzlein taken the hostage, Omar would have defended c6 with his elephant, leading into a class of positions that is very poorly understood to this day. Opinion varies wildly both as to whether Gold or Silver would stand better in the resulting position, and as to what strategy each player should pursue." ... that surprised me, as I though it was an established fact that taking a H hostage with an E is disadvantageous - or is it only if a bot does it?

15w: "Fritzlein believes that the camel hostage will be worth more than a cat, and Omar thinks the cat will be worth more. The last word on this trade-off has not yet been written" ... again I'm surprised, as I thought that most people now say that a camel hostage is worth a dog?

19w: "Omar takes advantage of the temporary misplacement of Fritzlein's pieces lauch an elephant-horse attack on f6." - missing word and also launch is misspelled --> "Omar takes advantage of the temporary misplacement of Fritzlein's pieces by launching an elephant-horse attack on f6." Also "effective" --> "effectively"

28b: "His own west wing is now too depleted to flip Omar's horse to b4 and launch a goal attack" --> "The east wing is now too depleted to flip Omar's horse to g4 and launch a goal attack" ... or words to that effect.

31b: "If Omar gets the camel hostage, Fritzlein might not get as much as cat in compensation like Omar did in the opening." --> "If Omar gets the camel hostage, Fritzlein might not get as much as a cat in compensation like Omar did in the opening."

41w: "He therefore launches the attack on c6 that he could have started on 40b." --> "He therefore launches the attack on c6 that he could have started on 40w."

45b: "Fritzlein decides has time to play the material game for one more move, time that his c7 dog buys him." --> "Fritzlein decides he has time to play the material game for one more move, time that his c7 dog buys him."

46b: "Fritzlein does the minimum to defend while pressing his western attack." --> "Fritzlein does the minimum to defend while pressing the eastern attack." ... or words to that effect.

48b: "and again calls into question Omar's refusing to offer it as a hostage on 45w." --> "and again calls into question Omar's refusing to offer it as a hostage on 43w."

Title: Re: Looking for tips on strategy
Post by Ryan_Cable on Mar 20^th, 2006, 10:34pm

East and west are symmetric when gold is setting up so 1w only really has 32,432,400 possible moves. The 1b number is correct since gold’s setup always makes the board asymmetric.

I think 22b ce6w ef5w eee5n rh8w would have been a better move. I think the game would then continue with 23w Ef7w Ee7w cd6w Ed7s 23b de8s de7e ee6s ee5e, which I think leads to a D frame or a trade of D for C.

Title: Re: Looking for tips on strategy
Post by Fritzlein on Mar 21^st, 2006, 1:44pm

on 03/20/06 at 19:48:09, Swynndla wrote:

I have a few questions if I may, and I have also suggested fixes for possible typos (although I'm not sure about the east-west ones, as sometimes you refer to the east wing as Silver's west wing, and this is a bit confusing for me). I didn't think you'd mind, Fritzlein, if I pointed these things out (along with my questions) in this forum rather than emailing you, so I hope I wont offend you.

Thanks for the all questions, corrections, and suggestions. I'm happy to get any feedback whatsoever. It would be fine to edit the Wiki directly, or fine to send me e-mail, or fine to let me know when you see me in the chat room. Posting in the Forum is good too, since that encourages more people to give contradictory opinions.

I intend for east and west to be absolute directions as Omar's movement notation suggests. Silver's west wing should be the same side of the board as Gold's west wing. However, you may have noticed that I sometimes get confused....

Quote:

5w: "Current opening theory suggests that it is bad to give up a horse hostage on a wing where the opposing game waits," ... do you mean the opposing camel waits?

Right, I meant camel, thanks. Fixed.

Quote:

5b: "A plausible alternative attack would have been to push Omar's e3 horse to d3, unbalancing Omar's forces by putting both horses on the same wing, but that wouldn't be to Omar's disadvantage unless Fritzlein switched wings with his camel as well." ... (italics mine) not clear ... do you mean that if both camels were on the opposite wing, then Gold's east wing would be weaker, and vulnerable to such things as a E-H attack (whereas with the camel waiting, the east side isn't weak for Gold, as the camel is there to defend ... and Silver's camel cannot increase the pressure on the east wing while Gold's elephant is there, or it'll be in danger of being taken hostage)?

Ah, I can see how that is not clear. I mean that if Omar had both horses on the same wing it could be a disadvantage to him if I also got my camel on that wing. Since you don't want to launch an EH attack where the opposing camel waits, if you have both of your horses on the same wing as the opposing camel, you are sort of stuck attacking with the lone elephant instead of having the EH option as well. I tried to fix it: let me know if it still isn't clear.

Quote:

8b: "Had Fritzlein taken the hostage, Omar would have defended c6 with his elephant, leading into a class of positions that is very poorly understood to this day. Opinion varies wildly both as to whether Gold or Silver would stand better in the resulting position, and as to what strategy each player should pursue." ... that surprised me, as I though it was an established fact that taking a H hostage with an E is disadvantageous - or is it only if a bot does it?

Bots can be crushed on either side of the EH, although they are beaten more often defending it since very few are willing to launch it. The very first way I learned to beat Bomb (2004 version) was by taking a horse hostage with my elephant.

In human games there is a lot of unexplored territory surrounding horse play. One idea is for the elephant to hold the hostage horse on b5 instead of a6, keeping a defensive horse on b6. (Doesn't it just feel right to have one's horse on b6 rather than one's elephant?) Then the hostage-holding elephant is just as centralized as the defending elephant. If rabbit comes up to unfreeze the horse, then one can play against the rabbit rather than the horse. I guess the state of the art is to unfreeze the horse with a dog. I don't know what to do then: play against the dog?

A second idea is to frame the hostage horse. Adanac posted in another thread that framing a horse is a disadvantage to the framer if the defending elephant is on the correct side. That is to say if I frame Omar's horse on c6, Omar actually benefits from this as long as his elephant defends from d6. I respectfully disagree. Of course it depends on the configuration of the other pieces, but I think it is to the advantage of the framer more often than not. See the current Postal Tournament game Robinson vs. Ron Weasley for an extreme example of an advantageous horse frame. How to play with or against a framed horse is very much an open question.

A third idea is to take the horse hostage with the elephant only temporarily, with the idea of passing the horse off to one's camel. This can be quite slow if one's camel is on the other wing, and will probably result in the loss of at least a rabbit while it is taking place. However, a camel holding a horse hostage is sometimes worth more than a rabbit. See my most recent game against OLTI, game 26593, for an example. Of course, live games prove less about the soundness of a strategy than postal games do. Timing is everything in this type of game, and we also don't have a good understanding of the value of a camel holding a horse. I reference that game merely as an example of why it isn't a settled issue.

From replaying some of the PMertens' experimental games, my best guess is that the advantage/disadvantage of an elephant holding a horse hostage is between the advantage of pulling an opposing rabbit and the disadvantage of having your own own rabbit pulled. (One square of rabbit pull is the smallest unit of permanent strategic advantage) In other words, an elephant holding a horse hostage is an issue so finely balanced, it is usually trumped by rabbit pulls, never mind other, larger considerations.

* If you have an EH attack going and the other guy is about to take your horse hostage, usually break off the attack and pull his rabbit while you have the chance.

* If the other guy is about to pull your rabbit with his horse, usually be willing to decentralize your elephant to take his horse hostage to stop it.

* If you have a horse hostage with your elephant and the other guy pushes a rabbit to unfreeze it, push his horse back towards his side and get his rabbit in trouble instead.

* If you have a horse hostage and nothing else is happening you are probably marginally ahead because you can rotate your camel over and/or threaten a frame.

Quote:

15w: "Fritzlein believes that the camel hostage will be worth more than a cat, and Omar thinks the cat will be worth more. The last word on this trade-off has not yet been written" ... again I'm surprised, as I thought that most people now say that a camel hostage is worth a dog?

On the contrary, opinion is swinging the other way. It used to be that most people thought a camel hostage was worth more than a dog. My postal with Omar was just one of many games which moved popular opinion away from this valuation. Nowadays I am perhaps the only one left of the top players who, if forced to choose, would rather get a camel hostage while giving up a dog. Most other top players would prefer to capture a dog and give up their camel hostage in the process. Some, such as blue22 (Robinson? Omar?), will gladly give up a camel hostage for only a cat capture, but I guess that the median expert opinion is that a camel hostage is worth slightly more than a cat.

Quote:

19w: "Omar takes advantage of the temporary misplacement of Fritzlein's pieces lauch an elephant-horse attack on f6." - missing word and also launch is misspelled --> "Omar takes advantage of the temporary misplacement of Fritzlein's pieces by launching an elephant-horse attack on f6." Also "effective" --> "effectively"

28b: "His own west wing is now too depleted to flip Omar's horse to b4 and launch a goal attack" --> "The east wing is now too depleted to flip Omar's horse to g4 and launch a goal attack" ... or words to that effect.

31b: "If Omar gets the camel hostage, Fritzlein might not get as much as cat in compensation like Omar did in the opening." --> "If Omar gets the camel hostage, Fritzlein might not get as much as a cat in compensation like Omar did in the opening."

41w: "He therefore launches the attack on c6 that he could have started on 40b." --> "He therefore launches the attack on c6 that he could have started on 40w."

45b: "Fritzlein decides has time to play the material game for one more move, time that his c7 dog buys him." --> "Fritzlein decides he has time to play the material game for one more move, time that his c7 dog buys him."

46b: "Fritzlein does the minimum to defend while pressing his western attack." --> "Fritzlein does the minimum to defend while pressing the eastern attack." ... or words to that effect.

48b: "and again calls into question Omar's refusing to offer it as a hostage on 45w." --> "and again calls into question Omar's refusing to offer it as a hostage on 43w."

Fixed. Thanks. Sorry I'm so directionally challenged in my east-west orienation. :)

Title: Re: Looking for tips on strategy
Post by Fritzlein on Mar 21^st, 2006, 2:08pm

on 03/20/06 at 22:34:56, Ryan_Cable wrote:

East and west are symmetric when gold is setting up so 1w only really has 32,432,400 possible moves. The 1b number is correct since gold’s setup always makes the board asymmetric.

Fixed. Thanks.

Quote:

I think 22b ce6w ef5w eee5n rh8w would have been a better move. I think the game would then continue with 23w Ef7w Ee7w cd6w Ed7s 23b de8s de7e ee6s ee5e, which I think leads to a D frame or a trade of D for C.

Wow, nice move. Not only did I not see it at the time, I didn't see it in any of my later analyses. That just goes to show how much is there to be seen. I have added your move to the commentary.