Engine analysis and categorizing mistakes

Sort:

manudude02

Dec 25, 2016

I was just doing an engine analysis of my last game, and came into something a little curious. First I show the stats according to the engine.

Strength	White	Black
Excellent	20	20
Good	6	3
Inaccuracy (?!)	3	4
Mistake (?)	1	2
Blunder (??)	1	2
Forced	2	1
Best Move	17.9%	42.9%
CAPS	6.71	47.08
Avg. Diff	2.26	1.53

If you ignore the last 3 rows, it looks as if white really should be better with having one less blunder, mistake and inaccuracy. Now I will show the game itself (with the engine analysis):

I know I was playing far from the optimal moves, but having lost my castling rights early after my opponent sacrificed his bishop, I just wanted to play the most solid chess I can (especially when he loses a rook for no reason too) and not go on potentially reckless attacks. By the end of the game, white is completely lost. It does bring up the question though, what defines what is a blunder or a mistake? I assume an inaccuracy is just things like mixing up the move order or not putting a piece on its optimal square.

Also, how are missed mates categorized?

Martin_Stahl

Dec 25, 2016

I don't know how they are defined here, but each category is associated to a specific change in engine evaluation.

So, an inaccuracy may be a drop of 0.30-0.60 in evaluation, a mistake might be 0.61-1.0 and a blunder could be any larger evaluation change.