The Chess Variant Pages
Custom Search




[ Help | Earliest Comments | Latest Comments ]
[ List All Subjects of Discussion | Create New Subject of Discussion ]
[ List Latest Comments Only For Pages | Games | Rated Pages | Rated Games | Subjects of Discussion ]

Comments/Ratings for a Single Item

Later Reverse Order Earlier
This item is an article on pieces
It belongs to categories: Orthodox chess, 
It was last modified on: 2014-12-24
 By Charles  Gilman. Man and Beast 02: Shield Bearers. Systematic naming of divergent coprime radial pieces.[All Comments] [Add Comment or Rating]
Jeremy Good wrote on 2014-12-10 UTC
Might we substitute the word "can" for "must" in your description of pawns' initial steps? Why?

"WARHEAD Pawn: both steps must be capturing (more aggressive than the above)"

- to say that both steps MUST be capturing is not to make the Warhead pawn more aggressive but to allow the Warhead pawn an initial double step only in the extremely unusual event that two pawns are lined up for it to take. Since an opponent is unlikely to allow that to happen, in practice, that means the Warhead pawn is unlikely to be able to make an initial double step at all.

So in practice, makes it more passive, not more aggressive (unless we substitute "can" for "must.")

Edit: I see my comment is insufficient in light of how you use "may" to introduce combinations of initial-step pawns. I will review and comment again later, unless someone can clear all this up in the mean time. I am now thinking perhaps we can create an even more comprehensive list that is also more plausible - unless you already did that, Charles. I wouldn't put anything past you when it comes to creating authoritative lists.


J Andrew Lipscomb wrote on 2013-05-22 UTC
On the prefixes: given the four "basic" (European, Warhead, Ambush, Nonchalant) patterns of capture/non-capture allowed, we have prefixes for those with zero (Ancient), four (Eurofighter), or two (all six ways) powers. Missing are those with three. Proposals: anti-European (must capture at least once): HUNGRY anti-Warhead (may not capture twice): DIETING (no second helpings!) anti-Ambush (if first is passive, second must be too): ELECTRIC ("It has to warm up... so it can kill you" of Wednesday Addams' electric chair) Anti-Nonchalant (if first is capture, second must be too: ADDICTED (gotta keep killin'...)

Jeremy Lennert wrote on 2011-12-31 UTC
Good point. Perhaps the value-tests for weak pieces should be performed with armies that include even weaker pieces, such as Wazir, Ferz, or Crab, to reduce the impact of the leveling effect. (One might argue that Pawns should suffice, and perhaps they do, but they are very weird pieces.)

H. G. Muller wrote on 2011-12-31 UTC
Well, it could be that the end-game value of mKcN is indeed lower than that of a pure Commoner, but that this is masked because the superior forking power makes it very likely you can always trade it for another minor in the midle-game. I measured opening values only. If that were true, the lower intrinsic value of the mKcN would only be revealed when there is nothing to trade it against, or if all the opponent's minors would be weaker than Commoners.

Jeremy Lennert wrote on 2011-12-30 UTC
Thanks once again for your very interesting computer tests, Mr. Muller! Notice that if this were simply a matter of the K capturing moves being unusually strong and the K non-capturing moves being unusually weak, we should expect mKcN to be weaker than K, but (if I am reading you correctly) the tests say it is stronger. So if you are correct that K's moves have a higher 'ideal value' but are suppressed by K's overall low speed (which would have been my first guess also), then we must conclude that a piece's 'speed' depends significantly upon its capturing moves, not only its non-capturing moves. This seems surprising to me, because I would imagine that capturing capabilities are only exercised in a small percentage of the piece's movements. Alternately, this could be a matter of special synergy rather than a global bonus or penalty--that is, perhaps the combination of speed and concentrated attacks is particularly valuable, but neither component has significant value by itself. Thus, the mKcN, lacking both, is not significantly worse off than either N or K, which only have one each, but the mNcK stands tall with both. Curious.

H. G. Muller wrote on 2011-12-29 UTC
I have done computer measurements of the piece values of the divergent combinations of Q and N and K and N in a FIDE context. The results supported an earlier observation, that a 'Lion' (Betza WFADN) would lose about twice as much value by disabling one of its capture moves (e.g. fW) as it would from disabling the corresponding non-capture. The value of mNcQ was around 7, that of mQcN around 5 (so 2/3 and 1/3 on the way between N and Q, respectively). The results for the K+N chimera was more surprising. Here we start with pieces thatare already very close in value, so that the interpolation does not do much, and cooperativity effects stand out more visibly. The conclusion was that a pure K (Commoner) is slightly weaker than a pure N (about 0.3 Pawn values), and that mKcN is quite close to pure N, as expected. But the surprise was mNcK, which came out about 0.5 Pawn stronger than pure N! My speculative explanation is that there are some terms in the piece value that depend on global properties of the move pattern (rather than contributions from individual moves). Like the K value is suppressed because it is a 'slow' piece, (it cannot overtake a moving pawn), but ehanced because of 'concentration' of its capture moves (it can at the same time attack a Pawn, the square in front of it, and the Pawn that protects it). The mNcK has the best of both: concentration of the capture moves, and speed of the Knight.

Jörg Knappen wrote on 2011-12-28 UTC
The only measure to get solid information about the strength of a certain piece is to playtest it (in human play and/or computer play). As far as I know, there are few divergent pieces really tested. Mike Nelson's Seperate Realms Rook comes out on a value of about 75% Rook plus 25% Dabbabarider, suggesting that capture constitues about 3/4 of the piece value, while moving alone constitutes about 25%. But this particular piece has rather similar move and capture patterns; the more the patterns diverge, the more playtesting is needed, and there is probably no simple formula describing the results. Note also that the results of playtesting depend on the testbed: What board is choosen, what is the oppenent's army, what pieces are in the same army (sociability effects).

Charles Gilman wrote on 2011-12-28 UTC
I was expecting some backing on this for other CVP contributors, but there has been none and I could not see anything on the Pieclopedia's Pawn page about the relative strength of divergent pieces either. For that reason I have removed my description of what I had previously thought was the consensus on pieces' relative strengths. If anyone else can shed light on this I would be grateful.

Charles Gilman wrote on 2011-12-15 UTC
The idea that the Ferz might be stronger thean the Steward is new to me. The Ferz cannot even reach the whole of the board. Is the Ferz stronger the even the Wazir. I would say that on an edge,let alone in a corner, the Ferz is the weakest of the three because of its fewer immediate destinations. The Pawn is a harder call as it will on average have fewer destinations than the Cross, but eight Pawns in a row are certainly stronger than eight Crosses in a row. It is easier to build up chains of non-mutually protected Pawns, and a Pawn on one side can protect while that on the other side progresses. I would be interested to know the views of others. Whose view is nearer the general consensus, if there is one?

Jeremy Lennert wrote on 2011-12-13 UTC
I remain skeptical even of your revised claim. Even when the components are non-overlapping and 'similar' (though I can only guess what that means), I see no obvious reason that having divergent capturing and non-capturing moves is better than having the same in the general case; only the capture or non-capture will be legal in any given position, so there is no loss due to 'overlap'. In fact, I've seen the opposite argued, on the grounds that a divergent piece is easier to trap, since it is unable to attack enemies in its way. When the combination lifts a special disadvantage (such as colorboundness), that is a special case; though it would need to eliminate a disadvantage from EACH of the components in order for that to make it stronger than BOTH, in general. (And I am unconvinced that lack of triangulation is a disadvantage of any measurable significance.) If the components were instead Crab and Barc, or Rook and Nightrider, what then? Comparing a Pawn to a Point is like comparing a Queen/Knight divergent piece to a Knight; that is obviously the weaker parent (Ferz is already stronger than Wazir, and loses much less from the forward-only restriction). I strongly suspect that the Pawn is weaker than a forward-only Ferz, despite the Ferz being colorbound, because the fF has more possible moves and does not need to capture to change files (the latter advantage being especially important if promotion is allowed). What is your evidence or reasoning for valuing divergent pieces more highly?

Charles Gilman wrote on 2011-12-12 UTC
You are right to say that my claim is not true of divergent pierces in general. In the case of Ajax pieces and the like it doesn't even make sense, as an Ajax Rook cannot be both stronger and weaker than a Chatelaine. I would also acknowledge that a Stewapacifier is weaker than a Rook. The claim was originally made for ther Pawn, the Steward, their direct analogues, and the riders of such pieces. Unlike a Wazir or Ferz, a Steward can triangulate - albeit in fewer circumstances than an unrestricted Prince. The fact that a Pawn can change file makes it stronger than a Point. How a Bishop, Pawnsnatcher, and Yeomapacifier compare I would be interested to hear given that the Bishop is colourbound and the other two are not. I have rephrased the introduction accordingly.

Jeremy Lennert wrote on 2011-12-11 UTC
You write, '[Divergent] pieces are stronger than either non-divergent piece, but weaker than the unrestricted compound piece.' This seems exceedingly unlikely. You seem to be claiming that a piece that moves as a Queen but captures as a Knight is stronger than either; in fact, read strictly, I believe you are claiming that a piece that moves as a Queen but captures as a Bishop is stronger than a Queen, even though it has strictly fewer moves. I believe conventional wisdom is that such pieces (which George Jeliss calls 'snipers') usually have a value that is somewhere between the strengths of the non-divergent pieces, closer to the capturing component than the non-capturing one. (Though I'm certain it is possible to craft examples that violate this rule.)

George Duke wrote on 2009-08-29 UTC
Strong Pawns along with ones found here in Shield Bearers include: (1) Centennial quadra-Pawns called Steward. Gilman's Shield Bearers does discuss this type in the paragraph beginning ''promotability.'' (2) Ninja Pawns of such as Wreckage and Venomous (3) Cannon Pawns of Rococo (4) new MaoJu pawns of LiQi. Which of those four are strongest in value in most piece mixes and sizes? It is not always considered that piece and Pawn values depend on their milieu, but usually there are clear trends, when spotting a pawn-type across row two of number of differing back-rank arrays, for comparisons. So, here only one of the above four can be said, by and large, most often to be clearly upwards of 2.5 points. Which one is so worth more than the other three?

Charles Gilman wrote on 2009-06-17 UTC
This article isn't especially advocating one piece over another, although I have now added some comments of the advantages of different pieces in different orientations. I have clarified some points.

George Duke wrote on 2009-06-15 UTC
One down and twenty to go, by then there is 21. Betza's worst fear is realized from Chess Different Pawns: ''If you can find alternate Pawns, I will be in awe, taking my hat off to you. I now fade away leaving nothing behind but an evil grin.'' Why is the familiar Pawn correct anyway? And Berolina or any other not. Because two ways capturing divergently enable tight formations widely spaced. Why is one-step-only the best after opening? So Pawn is noticeably less than Knight excluding dire mates imminent. Pawns Gilman calls divergent as they move and capture differently. Other piece divergencies appear earliest in Winkelspecht's Divergent Chess on this site. Gilman even re-names Shatranj Pawn to Ancient Pawn and modern Pawn to ''European Pawn.'' Warhead, Ambush...Helmsman have two modes of capture, one the regular divergent in the two directions and other by the double-step special case once a game per pawn. What about Pawns in some CVs always having two-step option on large boards? Not yet attempted to be named by Gilman in all their extrapolations.

15 comments displayed

Later Reverse Order Earlier

Permalink to the exact comments currently displayed.