Q: which ratings would you beat if you recieve an extra P/K/B/R/Q?

Things that go *bump* overnight :)

Ive made a graph using the information from this thread. It's a bit difficult to read what it says, but I hope I can explain a bit.

I have dont a couple things:

1) Made a table with everyone's estimates ("My rating" - P.rating - N/B.rating - R.rating - Q.rating)
E.g.:

2) Then a table with the piece's worth in rating (=own rating - estimated rating that they would beat per piece) 

E.g.:

3) I normalised all values to the pawn ((N/B)/3, R/5, Q/9)

E.g.:

So what do we get? Well... its hard to get an easy read. Im at work and have to go coffeedrinking. Ill be back in an hour or so to tell a bit more about the graph.

This one is easier to read:

This is the graph of the table after the 2nd step:

2) Then a table with the piece's worth in rating (=own rating - estimated rating that they would beat per piece) 

E.g.:

In this case I thought I could take on a 1200 player with an extra pawn. So 1200-1150 = 50. I estimated the pawns worth 50 ratingpoints. The knight/bisshop 125, rook 150 and Queen + 300 points.

Samplesize is to small, and two people around 1500 have to high estimates (or I took the wrong personal rating).

This experiment would get interesting if 1000s of people would enter their estimates. Especially if their estimates where based on multiple tries of games with different piece odds. So even better: computers using the results of many handicapped games!

That is because in Economy Chess players can play a handicap in two ways: by recieving starting money or by having cheaper prizes to buy a piece ($$$ or % discount). The player gets an economical advantage and it is up to him how efficiently he uses it. A bad player would buy double rows of pawns, good players buy what they need and when they need it.

pellik wrote:

Im gonna check that out, could be usefull as well!

Being frustrated not being able to defeat the Mephisto London chess computer (at any level) I resorted to removing its' f7 pawn and I won every time with ease.  How relevent chess engines are to the dicussion is another question.  With a piece advantage I would rather face an engine than Paul Morphy. 

I've an old book published in the 1800's detailing openings for odds games.  the various odds were

1. f7 pawn,

2. f7 pawn + extra move (ie white has 2 moves)

3. exchange odds ie., N for R.  I feel this is the most interesting as the rook is slow to come into the game while the knight is very fast.

4. N etc etc.  

 Handicapping is not all that straight forward as the odds giver often gets some compensation.  In the case of conceding a pawn you get open lines and if conceding a rook (usually the queen rook) your opponent  must survive the opening to be able to get his extra rook into play.

Which book?

I'd say 2) is a greater handicap than 3). 3) doesn't really come into play until the late middlegame, and the weaker player may already be well on his way to losing by then anyway. 2), on the other hand, would be crippling.

As regards open lines for a pawn, it depends which pawn. If it's the f7 pawn, I think the weakness created in the kingside far outweighs that. It would be more true for a7 or h7 pawns.

I would say  

rating:1865

pawn:+1000

minor piece:bishop+6555/knight+6550

rook:+8500

queen:10,000

all pieces:+199,999