Watching over the game Mirko Rahn (black) vs. Eobllor (white) : http://www.littlegolem.net/jsp/game/game.jsp?gid=1747939 I discovered to my amazement today that the current 15th Havannah championship is played with swap rule!

Unfortunately the only player that partly noticed the rule change was Eobllor (but only after 1. move), and all us other 1. league players did not, which gave stupid 1. moves in all of the games (including Eobllor who opened with 1.j10).

The point is of course that the players need to be informed better about the rule changes - otherwise you get situations like Havannah 15.1.1 where all 9 players thought old rules while playing their first move, and 8 players thought old rules wile playing their second move. I guess for instance that Mirko was quite amazed when he saw his 1.k4 swapped! :-)

It was repeatedly mentioned on the forums that it was going into effect. I can imagine a banner or something on games being a nice touch, but it was mentioned.

As for the championship, I believe most games started with swap not in effect–it was introduced right around the beginning of December (http://www.littlegolem.net/jsp/forum/topic2.jsp?forum=50&topic=639). But maybe the first two moves in this game were slow?

Wow! what you write Hyperape makes things so much worse!! In did Eobllor was slow to start, and as you implicate once he could make move number two he had the swap option an could swap all his white games, which practically made him the starter (black with old rules) in all his championship games. This is one of the worst bugs I have ever seen! Sad for all the 9  Havannah champ. 15.1.1 players as no one wants to get illegal advantage or disadvantage.

True, this came as a surprise to me. And it might be true that a British gentlemen would not have taken the opportunity to swap in this situation. However, the rules are made by Richard and came into effect at some point in time. One might consider it a bug that the rule change applied to games in progress too, on the other hand the community asked for the swap rule for all sizes and the effort for Richard to enable it only for new games certainly would have been higher.

After all, it is how it is and the game was not decided just because of the swap. :/

Still we have no clear evidence of the advantage or disadvantage of the swap-rule at boardsize 10. It would be very interesting if someone could investigate what the percentage of win for black at boardsize 10 was, especially at the championship games.

It is not easy being aware of all potential possibilities so I am not blaming Richard, however I hope this thread can help in future - hindering similar situations occurring again, say in some other games on LG.

Well Tony, in fact I have done some research on the topic. I have taken the score from all Havannah championship games on 1. level up to the 14th championship. So based on 525 games black scored 54,86 % which is quite similar to chess.

However caution must be taken as there are relatively big rating differences in 1. level Havannah championships between the players. My point is that ideally for such statistics to become true we want study games between even leveled players. Just think of 2200+ players like Fritzd or Mirko Rahn - they will win most of their games no matter color.

So you need some estimates and I think that a size 10 game between two even players gives the opener say a 58-62 % advantage which of course is quite high. Using the statistically correct Jeff Sonas formula (2011) this gives the black player something between 65-100 rating point advantage.

I indeed wasn't aware, when the tournament started, that the swap rule was in effect (and as I understand it now, it wasn't), so that I opened in the centre as I usually do. But when I played my first move as second player, I saw the swap button available; thus I thought the swap had finally been implemented for this tournament without my being aware of it. As the swap was an option I considered necessary (I didn't perform stats like Kokosz, but have a strong feeling of the game being much easier as first player) and as I felt the first moves of my opponents were good ones, I swapped. Unfortunately, I didn't take a look at the other games beforehand, and I vaguely told myself that the good first moves of my opponents just meant they didn't care much about the swap or didn't estimate the value of these moves as I do; only afterwards did I realise I was the only one who swapped! I was quite sorry about the situation, but felt there wasn't much to do. Anyway, if it is still possible and not too tedious, I don't mind playing replacement games with the same first move, in which I wouldn't swap.

As for our game, Mirko, it may not have been decided by the swap alone, but I know how this kind of unexpected disagreement can bend the result… So, again, if you will, we can play another game in which I won't swap (whether it be possible to make it replace the game of the championship or not).