Very low computer elo.. game bug?

[gsd972]

When i start a single game against computer this is the elo is see and it seems completely off..

Scholar - 1456
Professional - 1481
Master - 1501
World Master - 1428
Grandmaster - 1386

Is anyone else seeing this?

Why is Grandmaster be lower than World master and master? And GM should be around 2400+

[Mattchess]

The elo ratings are recalculated after every game based on opponent ELO. My guess is more low rated players are cheating against the grandmaster level engine (following moves from a UCI engine on their PC or phone) to get the achievement for beating various engine levels and this has dragged down its ELO. Alternatively, the engine level may have a glitch in its opening book that some players have learned to exploit. For example, the amateur level always plays the french against me and seems to have difficulty with the exchange variation (with c4) making some poor piece trades :P I'd like to see a more diverse opening book.

It may have been wise to restrict ELO adjustment against the computer to the results of 5 minute blitz games, where a player has less time to consult an engine or let it get to any depth and not count longer time controls against AI for the purpose of rating adjustment.

[Ripstone]

Each AI level has a set difficulty rating, so Amateur will play at the same level every time. BUT, Amateur's ELO will change depending on how the community is performing against that specific level. So if more players are losing to Amateur than winning, the ELO will increase. This explains why for example, the rating for Amateur could show temporarily higher than Expert for example.

The difficulty of each set AI level does not change, but the ELO rating is currently showing how it is performing against the community. We're experimenting with this at the moment to see whether it levels out or not, as we understand it can be a little confusing.

[Mattchess]

One suggestion is to limit the number of rated games someone can play against each engine level in a given period of time. That would not mitigate elo deflation from people going after achievements with engine assistance but it would limit elo deflation from repeated wins against the engines. You could couple that with a rating floor for each AI level. Allow ELO variation but don't allow the rating to drop below a floor. Between those two adjustments, things should level out. People would not be able to abuse the floor to inflate their own ELO because of the rated game limit.

[gsd972]

I thought it would have something to do with the opponents ELO and in that case yes if many people cheat against it, it would drop but is the strength of the engine preserved or does it degrate as the elo decreases?

I was playing against the "World Master" difficulty and it has started making random blunders sacraficing pieces to the point of no longer offering any challenge.. plus it always plays the same opening

It does seem a little strange how in single player mode, the engine's elo would be affected by others..