Ab : can I refrase your question : " When is a grandmaster resigning ? " , followed by the decision to note down the score " 1-0 ".
So no calculation, just a decision by a player.
Next question could be : " Why is he resigning ? ", well, when there is absolute NO possibility to win or to play a draw, so the position on the board is deciding, it's of no use to play on.
Talking about calculation : in the tournament in Monte Carlo in 1901 they tried to use another system, only 1/4 point each by a draw ; they had to play again and the winner gets 1/2 point and the loser zero, so e.g the match Janowsky-Marshall ended in 3/4 - 1/4 . But that's history !
A lot of forums here is written about draws, that's another subject.
Hello guys ! i am bit in doubt about my knowledge of grandmaster games so i had this question , does anyone of you have any clear idea how score 1-0 is calculated or DECIDED .. in higher rating games , where is only least chances of CHECKMATE ! i mean there is only possiblity of draw how do we calculated that game is 1-0 SCORED , i know the values of all pieces ...but very blurred about the rating idea ! Please help !