Chess Engines and Elo Ratings

Question

I don't know if this question has already been asked. Pardon me if it was.

1. What is the difference between a human player of approximately 1600 ELO rating and a competent chess engine like Stockfish 7 set to ELO 1600 (in Fritz you have such an option under Training > Rated Game)?

[Don't know if my second question is particularly connected to the first, but here it is:]

2. Is it possible to determine the ratings of players by the PGNs of their games? I'd rather play with a computer and wanted to know what my Elo is. Is it possible through Fritz or any software?

[This is more of a side question]

3. Is there any site that explains what is Elo in lucid terms?

Answer 1

1. What is the difference between a human player of approximately 1600 ELO rating and a competent chess engine like Stockfish 7 set to ELO 1600 ?

The main difference is in the way each chooses their moves.

The human player will predominantly use pattern recognition combined with some form of plan recall. So, I recognize that this position is winning for white and this is the winning plan. This might involve specific moves for a tactical plan and more general aims for a strategic one.

The computer will predominantly use brute force calculation with an element of pattern recognition for position evaluation

2. Is it possible to determine the ratings of players with the pgns of their games?

In theory, yes. Both FIDE and certain online chess providers have looked at tools for detecting cheating which essentially do this although without producing a rating. They look at moves which are not opening book / standard theory moves and calculate the percentage of moves which are engine 1st, 2nd, 3rd choices etc. In principle this work could be extended to develop a way of rating pgns but it would be a lot of hard work.

I'd play with the computer and wanted to know what is my ELO. Is it possible through Fritz or any software?

No. Too much work to develop such a system for too little reward.

3. Is there any site that explains what is ELO in lucid terms?

Since you appear to know what ELO is (an internationally recognized rating system) presumably what you are really asking is whether there exist explanations for the mathematics and statistics behind ELO.

The killer part of your question is "in lucid terms". Of course such explanations exist which are lucid for mathematical and statistical experts but just as clearly if you lack the expertise they will not be lucid for you.

Answer 2

I think you should ask three questions at chess.stackexchange.com instead of asking three times in a single question

What is the difference between a human player of approximately 1600 ELO rating and a competent chess engine like Stockfish 7 set to ELO 1600 (in Fritz you have such an option under Training > Rated Game)?

I don't know about this setting. I think the only way to weaken Stockfish is limiting its search depth, so I guess that's what Fritz does, but I don't know.

Maybe this question and Student T reply can help you.

Is it possible to determine the ratings of players with the PGNs of their games? Rather, I'd play with the computer and wanted to know what is my ELO. Is it possible through Fritz or any software?

There have been several attempts to calculate player's ELO from the difference between the played moves and the best moves (as calculated by a chess engine). There's an obvious correlation between both values. You can find some information at Computers choose: who was the strongest player?, Computer analysis of world champions or Determining the Strength of Chess Players Based on Actual Play

Is there any site that explains what is ELO in lucid terms?

The Wikipedia article on Elo Rating System is rather good. There's an interesting statistical studio by Sonas The Sonas Rating Formula – Better than Elo?