Question: Title question, basically: do engines have a larger advantage over a human at long or short time controls? Have any studies been done on this?
Context for the question: On a reddit thread yesterday someone pointed out that Andrew Tang beat Leela in an ultrabullet game around four years ago. I was astounded by this -- I would not have thought this possible. (Leela was rated around 3250 on Lichess at the time, so she had been trained quite a bit there) I mentioned this to a buddy of mine, and his contention was that humans will perform better against engines at shorter time control. I thought that was flat out wrong, but set out to prove that point.
Unfortunately, I was not able to find much in the way of hard data. This best I could find was this experiment done by the folks (guy?) who runs FGRL that compares search depth against time. It seems that doubling the amount of thinking time approximately increases the search-depth by 2-ply. I have no idea how search-depth corresponds to playing strength -- the best I could find was this paper from 2013 that suggests that an increase in search depth of 2-ply is an increase in playing strength of approximately 120 rating points.
So, my best guess at this point is that doubling the amount of thinking time increases the engines rating by around 120 rating points. When I made the argument that engines have a bigger advantage at shorter time controls, I did not expect a 2-ply increase in search depth to increase the playing strength by 120 rating points, I expected it to be considerably lower.
Grandmasters also play exceptionally well at short time controls. How much do they gain by doubling the time. Is it 120 rating points? I don't know. Do you? This is what made me doubt my initial conclusion, and prompted this question.
Is the 120 rating point increase in computer playing strength by doubling its thinking time a reasonable conclusion?