King's College London

At the highest level, games between Grandmasters end in draws far more often than they end in victory - about 60 percent of such matches conclude with no winner. But when a match or tournament finishes tied, someone still has to be crowned champion.

How have ties been handled in the past?

The game’s attempts to solve this have ranged from the sensible to the surreal: in 1983, for example, a tied Candidates match between Vasily Smyslov and Robert Hübner was decided by a roulette wheel in a casino.

In the 1990s, a new solution to settle ties was introduced, Armageddon: a single sudden-death game in which the person playing white must win outright, while the person playing black only needs a draw to take the match.

To offset white's tougher task, the player is given extra time on the clock. But how much extra? Some tournaments now let players bid, in secret, for how little time they'd accept to play black. Critics say it is a guessing game and blind gamble as much as a game of chess.

Is there a fairer way of settling things?

Two academics, Mehmet Mars Seven, of King’s College London, and Steven Brams, of New York University, think so and their new proposal is inspired by the Hebrew bible.

Their system, ‘divide and choose’ draws on the method cited in the Book of Genesis by which Abraham and Lot divided land in Canaan - also known as ancient Israel. To allocate the land, one person divides it into two pieces, and the other person chooses the piece they prefer.

When applied to chess, the academics stipulate that both players share a fixed total clock, set at 30 minutes, to keep match lengths predictable for organisers and broadcasters.

The person who played black in the most games then takes white and becomes the ‘Divider’, with a coin toss breaking a tie. The Divider proposes, for example, a 20–10 split.

The Chooser picks a portion: the longer time requires a win; the shorter time only a draw. The ‘Divider’ sets the times to a balance point where they would be equally satisfied playing either side.

The opponent (the ‘Chooser’) reviews the offer and selects their preferred side, leaving the ‘Divider’ with the remaining option.

“Unlike the uninformed choice that each player must make to render themself indifferent to the preset time of white under Armageddon, divide-and-choose gives the ‘Divider’ the opportunity to render themself indifferent to the subsequent preferred choice of the ‘Chooser,’” the authors said.

“Thereby, the players have a greater ability to co-ordinate their choices and make more informed decisions.”

In the biblical story, Lot chooses the greener pasture but is soon beset by problems and ends up ruined and living in a cave. The academics hope for a happier outcome for their system.

The work, “Eliminating Draws in Chess: From Armageddon to Divide-and-Choose,” will appear in the October issue of CHESS Magazine.