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If I understand this correctly, they are applying the Chess strategy of thinking n-moves ahead to Scrabble, where the opponent's tiles are hidden and ones own future tiles are mostly unknown.

If you use all the tiles, on the upside you get +50 extra points. The downside is that you leave a lot more room for the opponent to score big since there are more letters on board after your move. Also, you have no control on your next 7 tiles and this can negatively affect your scores for the next 3-5 moves.

The benefit to keeping a few good tiles for future moves comes at the cost of fewer points in the immediate round. The upside is your opponent has fewer open tiles to score big on.

In general, the first strategy beats the second because of the bingo advantage, however their secret sauce is a list of 5 letter words that the opponent can't build on to score big points. So these inert words make the second strategy better for now.

I haven't written any Scrabble AI but I wonder if most of them optimize for the immediate move or look further down the game? Unlike Chess, there are many more unknown variables per move in Scrabble - tiles you both might get, x-y position of n-tiles placed per round, scores of each tile placed, tile bonuses (double/triple letter/word) etc. If anything, the Nigerians' victory has shown that there is a lot more room for optimization in Scrabble and scoring the max per round may not be the globally optimal solution.

>> If I understand this correctly, they are applying the Chess strategy of thinking n-moves ahead to Scrabble, where the opponent's tiles are hidden and ones own future tiles are mostly unknown.

Yep, Scrabble is a hidden-information, stochastic game (the opponent's future tiles are also randomly drawn).

Scrabble is probably more similar to poker and other card games in that respect. The key difference is that the distribution of letter tiles is skewed: the number of tiles is not the same for each letter [1]. This is different than, say, playing cards, where you get exactly 4 of each card (plus the, I think two, Jokers).

Which means it's easier to make a prediction for what's coming out of the opponent's bag, possibly (they're more likely to see the more common tiles).

>> they are applying the Chess strategy of thinking n-moves ahead

Well, that's a universal m-player game strategy, not specific to chess. Minimax and all that, ja? Did I misunderstand what you mean?

Except of course in this case the optimal strategy for Scrabble seems to be under dispute (long or short words best?) and so programming an AI player with minimax might not be that straightforward.

[1] https://en.wikipedia.org/wiki/Scrabble_letter_distributions

On an unimportant note, jokers are not included in poker, nor in almost any other game. It is my understanding that they exist to use as replacement cards in the case of a lost or damaged card (rather than having to throw out the deck.)

Jokers are actually used in occasional uncommonly played poker games (certain variants of 5 card draw). For the most part those games haven't been played much in public card rooms since 10-20 years ago but you can occasionally come across a game.

"they are applying the Chess strategy of thinking n-moves ahead to Scrabble"

That isn't new, what is new is that they (learni from analysis of games played by computer) show is that the conventional strategy favours scoring points too much over keeping a rack that allows you to score decently in future moves and preventing your opponent from scoring heavily.

This is presented as a totally new strategy, but looking at the video showing an example game, I get the impression it is more of a slight, but important adjustment. For example, the Nigerian does have a seven-letter move in that play.

And, by the way, I would expect this:

"Mr. Jighere and his teammates kept to themselves, going to bed early […] his opponent, Mr. Mackay, spent the evening before their big match at a pub."

also influenced the result. McKay probably saw this as a bit of a holiday, while the Nigerians saw it as work. 449 vs 432 is not a crushing defeat.

OK you guys. Here's the serious bit then:

>> McKay probably saw this as a bit of a holiday, while the Nigerians saw it as work.

That's probably his way of unwinding and managing his psychology after a match. It's a bit misleading for the article to bring it up as a disadvantage since he's obviously a strong player who has probably competed for some time, so he should be expected to know what works for him.

Also, you can perfectly well go to the pub without coming back with your pants on your head. I usually drink half a glass of wine, then go home and code. No reason why the guy didn't have a light drink then got back to his hotel and trained.

By contrast, the Nigerian's practice of playing 48-hour games and studying non-stop during their flight sounds more performance-degrading to me (having played a board game competitively, I won't say which). But, again: what works for them works for them.

Agreed. The time before a competition is all about stress management.

48 hours of non-stop practice does sound a little extreme, but keep in mind that this is a one-time event in the middle of their training. Not right before the competition.

Avoiding burnout is certainly important in the long run, but short bursts of intense training, with recovery time afterwards, can indeed work well.

Stop.Just stop.You guys always begrudge success when Africans do good things.It is pathetic and low.You ought to learn to appreciate and celebrate people when they work hard to achieve success rather looking for ways to belittle their achievements.

Did you post this under the wrong message? I didn't write anything that sounds like I'm begrudging the Nigerians their victory.

You are projecting your personal issues into this conversation. Nobody has done what you just said.

>> McKay probably saw this as a bit of a holiday, while the Nigerians saw it as work.

Nah. A British gentleman will always go down his local for a pint after work :P

That last sentence is the real piece of news here - the absolute core of the issue: Nigerians have been doing extremely well at Scrabble by applying non-greedy strategies. It seems obvious in retrospect that a game like Scrabble is not played optimally by making greedy choices.

My friend was cheating against me in words with friends by looking up the biggest words. I beat him pretty handily with defensive play.

In words with friends you can easily control the double and triple words by avoiding plays that open certain areas of the board. There are more double words in Scrabble so WFF is more strategic in that regard.

Quackle[1] and Elise[2], two of the best Scrabble AIs, do look ahead.

[1] http://people.csail.mit.edu/jasonkb/quackle/doc/how_quackle_... [2] http://www.codehappy.net/elise/

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