user13544: I will clarify my question with an example:
A grandmaster plays a game against stockfish, with a material handicap for stockfish, and the advantage is not clear for either of the players. Throughout the game, the position is a dead draw. However, during the endgame, stockfish discovers a loss 50 moves later (100 ply). For the game, stockfish was set to resign the game if the evaluation of the opponent's position exceeds 900 centipawns for 5 moves (2 ply). Consequently, stockfish resigns the game.
Was this a wise decision? What if the human blundered? Did stockfish resign a game which probably could've been drawn?

user12629: For a computer, unlike for a human, there's no fatigue associated with playing on, so there's no reason for the computer to benefit from resigning.  But, if the organizers of a computer-human match or tournament want to attract human players, they may want to make some concessions like computer resignations.

Did stockfish resign a game which probably could've been drawn?

It's impossible to say.  Was the position a known theoretical win that every GM knows how to convert, or was it a position that you pretty much need a tablebase to navigate?  It is certainly at least possible for a computer programmed to resign in such situations to resign too soon.  Perhaps the parameters need to be tweaked so that a 900 centipawn for 5 ply position must be reached within the first 10 ply to trigger the resignation.

user13012: People have been known to resign for a variety of reasons, but it is chiefly a question of good manners. You should not insult your opponent by wasting their time and you will make yourself look a bit of a fool. I think that most questions about the timeliness of resignation among human players come down to defining what is and what is not an insult. Suppose that in a moment of blindness I put my Queen where she will be lost to a Knight fork. I probably don't resign until I see that my opponent has noticed, but as soon as they make the fork I probably should. However, there is no foolproof algorithm to decide the question. Gawain Jones won a game in the British Championship after hanging his Queen for almost nothing.
Since computers cannot insult or be insulted they need an algorithm, and it is very hard to come up with one. I think that quite often the operator/programmer resigns on the machines behalf.

user12873: It's never wise to resign a game if the only way you can lose is from some long, forced combination. There's a significant chance your opponent could miss it. In fact, in a typical chess position even Stockfish would not be able to calculate 50 moves / 100 ply ahead (unless the position was a simple endgame with few pieces).
It's only wise to resign if there's not a realistic chance of you not losing. In a situation where your opponent has to calculate a long forced variation, there's definitely a realistic chance he'll miss it.
Comparatively, if you're down a Queen in a quiet position against an opponent equal or greater than your strength, there isn't any realistic chance you won't lose (unless your opponent is really low on time).

user12449: The time to resign is when think your opponent will win.  Against a beginner, I would never resign, because they will most probably blunder and lose.  Against a decent club player, I could resign after being a rook down in a lost position.  Against a GM, I would resign after the 12th move if I thought I had a bad position (it's a good learning possibility to see the technique).  
I find it insulting to not resign when your opponent has a won game. (An exception can be made for cases like checkmating with a knight and bishop).
In the case of a computer, it can only do as it's programmed to do.  (Although humans now stop the game when an endgame database position has been reached to prevent the human from making a mistake the the computer looks up in a book.  This is cheating if a human did it, why not the computer?)  I don't think that the computer should resign this early, but he late should the computer resign?

user11629: For beginner players, who tend to blunder a piece or mate in one regularly, there is no point to resign early. Any game, even in (objectively) clearly lost position will help them to gain experience.
For more advanced players, the decision to resign will depend on various factors and cannot be generalized. 
Most importantly, an objectively clearly won/lost position can be of very different character. If it is a quiet, easy to calculate (e.g. endgame) position with few pieces on the board, and a clear easy to see winning plan, there is not much point to continue the game. On the other hand, if it is a wild position with lots of pieces and tactics, there are many chances for your opponent to go wrong and you would not resign immediately.
Some factors to take into account before resigning:

Do I have any chances for active counterplay?
Do I have any chances for drawing (building a fortress, stalemate,...)?
Is the position easily won for my opponent or is it rather a "theoretical" win, but difficult to do in "practice"? (e.g. 
How much time does my opponent have left?
Over the last couple of moves, did my opponent show that he understands how to play the position for a win?

Similar things hold for the question: "Should I offer a draw?".

13544: <p>I will clarify my question with an example:</p>

<p>A grandmaster plays a game against stockfish, with a material handicap for stockfish, and the advantage is not clear for either of the players. Throughout the game, the position is a dead draw. However, during the endgame, stockfish discovers a loss 50 moves later (100 ply). For the game, stockfish was set to resign the game if the evaluation of the opponent's position exceeds 900 centipawns for 5 moves (2 ply). Consequently, stockfish resigns the game.</p>

<p>Was this a wise decision? What if the human blundered? Did stockfish resign a game which probably could've been drawn?</p>
 12629: <p>For a computer, unlike for a human, there's no fatigue associated with playing on, so there's no reason for the computer to benefit from resigning.  But, if the organizers of a computer-human match or tournament want to attract human players, they may want to make some concessions like computer resignations.</p>

<blockquote>
  <p>Did stockfish resign a game which probably could've been drawn?</p>
</blockquote>

<p>It's impossible to say.  Was the position a known theoretical win that every GM knows how to convert, or was it a position that you pretty much need a tablebase to navigate?  It is certainly at least <em>possible</em> for a computer programmed to resign in such situations to resign too soon.  Perhaps the parameters need to be tweaked so that a 900 centipawn for 5 ply position must be reached within the first 10 ply to trigger the resignation.</p>
 13012: <p>People have been known to resign for a variety of reasons, but it is chiefly a question of good manners. You should not insult your opponent by wasting their time and you will make yourself look a bit of a fool. I think that most questions about the timeliness of resignation among human players come down to defining what is and what is not an insult. Suppose that in a moment of blindness I put my Queen where she will be lost to a Knight fork. I <em>probably</em> don't resign until I see that my opponent has noticed, but as soon as they make the fork I <em>probably</em> should. However, there is no foolproof algorithm to decide the question. Gawain Jones won a game in the British Championship after hanging his Queen for almost nothing.</p>

<p>Since computers cannot insult or be insulted they need an algorithm, and it is <em>very</em> hard to come up with one. I think that quite often the operator/programmer resigns on the machines behalf.</p>
 12873: <p>It's never wise to resign a game if the only way you can lose is from some long, forced combination. There's a significant chance your opponent could miss it. In fact, in a typical chess position even Stockfish would not be able to calculate 50 moves / 100 ply ahead (unless the position was a simple endgame with few pieces).</p>

<p>It's only wise to resign if there's not a realistic chance of you not losing. In a situation where your opponent has to calculate a long forced variation, there's definitely a realistic chance he'll miss it.</p>

<p>Comparatively, if you're down a Queen in a quiet position against an opponent equal or greater than your strength, there isn't any realistic chance you won't lose (unless your opponent is really low on time).</p>
 12449: <p>The time to resign is when think your opponent will win.  Against a beginner, I would never resign, because they will most probably blunder and lose.  Against a decent club player, I could resign after being a rook down in a lost position.  Against a GM, I would resign after the 12th move if I thought I had a bad position (it's a good learning possibility to see the technique).  </p>

<p>I find it insulting to not resign when your opponent has a won game. (An exception can be made for cases like <a href="http://www.chessgames.com/perl/chessgame?gid=1637420." rel="nofollow noreferrer">checkmating with a knight and bishop</a>).</p>

<p>In the case of a computer, it can only do as it's programmed to do.  (Although humans now stop the game when an endgame database position has been reached to prevent the human from making a mistake the the computer looks up in a book.  This is cheating if a human did it, why not the computer?)  I don't think that the computer should resign this early, but he late should the computer resign?</p>
 11629: <p>For beginner players, who tend to blunder a piece or mate in one regularly, there is no point to resign early. Any game, even in (objectively) clearly lost position will help them to gain experience.</p>

<p>For more advanced players, the decision to resign will depend on various factors and cannot be generalized. </p>

<p>Most importantly, an objectively clearly won/lost position can be of very different character. If it is a quiet, easy to calculate (e.g. endgame) position with few pieces on the board, and a clear easy to see winning plan, there is not much point to continue the game. On the other hand, if it is a wild position with lots of pieces and tactics, there are many chances for your opponent to go wrong and you would not resign immediately.</p>

<p>Some factors to take into account before resigning:</p>

<ul>
<li>Do I have any chances for active counterplay?</li>
<li>Do I have any chances for drawing (building a fortress, stalemate,...)?</li>
<li>Is the position easily won for my opponent or is it rather a "theoretical" win, but difficult to do in "practice"? (e.g. </li>
<li>How much time does my opponent have left?</li>
<li>Over the last couple of moves, did my opponent show that he understands how to play the position for a win?</li>
</ul>

<p>Similar things hold for the question: "Should I offer a draw?".</p>
