2013-02-15 last update, 1997-09-13 first day, Robert Jasiek

Basic Comparison

Rule Sets

• Simple : Simple Rules, 1997
• AGA : American Go Association, 1991
• Ing : Ing's SST rules, 1991
• CHN : Chinese Weiqi Association, 1988, mainland China
• JAP : Nihon Kiin, 1989, Japan
• IGS : Internet Go Server

Properties

• designed for professionals: maintenance of professional tradition strongly characterizes rules' concept
• widely used by amateurs: applied by many amateurs for informal or tournament games
• recommanded for beginners: simple conception, easy and quickly understood
• logical: no contradiction, handles any board position, no special exceptions
• further information

• normal even game komi: typical value for compensation points for white in even game; 8 komi for Ing resulting in a tie give black the win; 5.5 komi for CHN are counted as 2.75 half count komi; "not set" means leaving values for tournament rules
• handicap: handicap stones may be placed on any board points (free); else Japanese handicap on handicap points is used (fixed); the AGA rules allow either free or fixed handicap; some rule sets leave a choice to the players or for tournament rules ("not set")
• definitions, game end, game end classification

• suicide: allowance of self-removal of surrounded own stones after removal of opponent's stones
• ko: PSK = positional super ko (no repetition of whole board position), SSK = situational super ko (no repetition of whole board position if the same player's turn), Ing = fighting and disturbing ko depending on settlement of life and death, void = basic ko rule + no result for whole board repetition in complex kos (formally for CHN it is PSK + no result for exceptional kos; the effect is roughly the same)
• definitions, ko, ko classification

• scoring: which points determine the win; area = colored points + empty points surrounded by the color; territory = empty points surrounded by a color + opponent's prisoners; for AGA area and territory scores equal; in general area and territory scores are close since for each prisoner a stone misses on the board
• counting: if not set, point-by-point counting can be used; point = point-by-point counting (scanning the board or using a finger; it suffices to count one color); Chinese = Chinese half counting (like point-by-point half counting, but with much rearrangement of stones); fill-in = each color uses an equal number of stones that are all filled in so that only one board point remains empty; Japanese = put prisoners on board and rearrange
• additional phases: none = alternation is immediately followed by two game ending passes, all removals must take place before in alternation; agree = alternation is followed by stopping passes, an agreement phase (that can lead to resumption of alternation), and ending passes, during agreement the players verbally agree about removals; Japanese = alternation is followed by stopping passes, a confirmation phase (putting remaining dame and defensive moves inside territory on board), ending passes, and removals (done accordingly to complex rules using hypothetical play)
• final pass number: the exact reasons of various settings for numbers of passes are often lengthy and differ considerably
• pass stones: for each pass the opponent receives a stone; this enables equality of area and territory scoring
• dame valuable: dame are scored and thus should be played alternately
• score empty points in seki: Japanese rules traditionally exclude sekis from scores
• game end, game end classification, examples