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In 2010, Diogo R. Ferreira participated on a chess ratings competition offered by [https://en.wikipedia.org/wiki/Kaggle Kaggle] <ref>[http://www.kaggle.com/c/chess Chess ratings - Elo versus the Rest of the World - Kaggle]</ref> and made it to 4th place <ref>[http://blog.kaggle.com/2010/11/30/how-i-did-it-diogo-ferreira-on-4th-place-in-elo-chess-ratings-competition/ How I did it: Diogo Ferreira on 4th place in Elo chess ratings competition | no free hunch]</ref> . His approach is based on the [https://en.wikipedia.org/wiki/Pairwise_comparison Bradley-Terry model], but with a slightly different interpretation of what the [[Playing Strength|strength]] of a player is, and with a custom procedure for estimating that strength <ref>[[Diogo R. Ferreira]] ('''2010'''). ''[http://web.ist.utl.pt/diogo.ferreira/chess/ Predicting the Outcome of Chess Games based on Historical Data]''. [https://en.wikipedia.org/wiki/Instituto_Superior_T%C3%A9cnico IST] - [https://en.wikipedia.org/wiki/Technical_University_of_Lisbon Technical University of Lisbon]</ref> . In his [[ICGA Journal]] paper, ''Determining the Strength of Chess Players based on actual Play'' <ref>[[Diogo R. Ferreira]] ('''2012'''). ''Determining the Strength of Chess Players based on actual Play''. [[ICGA Journal#35_1|ICGA Journal, Vol. 35, No. 1]]</ref> , Ferreira elaborates on strength estimation based on a per move basis with the help of a strong chess program and distribution of gain. A gain was defined by the [[Score|score]] difference of [[Houdini|Houdini's 1.5]] fixed depth 20 ply search of all consecutive positions along the game-record, alternating assigned to the player who made the move. Four algorithms for different purposes were defined:

Ratings of various chess players and programs were estimated based on the distribution of gains from various games, [https://en.wikipedia.org/wiki/The_Game_of_the_Century_%28chess%29 The Game of the Century] between [https://en.wikipedia.org/wiki/Donald_Byrne Donald Byrne] and the 13 year old [https://en.wikipedia.org/wiki/Bobby_Fischer Bobby Fischer] was given as sample for algorithm 1 with game score differences, yielding in a rating difference of 113 points in favor to Fischer. The [https://en.wikipedia.org/wiki/London_Chess_Classic#2011_Classic:_3-12_December London Chess Classic 2011] <ref>[http://www.chess.co.uk/twic/chessnews/events/london-chess-classic-2011 London Chess Classic 2011] | [https://en.wikipedia.org/wiki/The_Week_in_Chess The Week in Chess]</ref> <ref>[http://www.chessbase.com/newsdetail.asp?newsid=7754 London R9: Vlad All Over], [[ChessBase|ChessBase News]], December 13, 2011</ref> was used as sample for algorithm 2 and 3, while algorithm 4 was applied for [[Kasparov versus Deep Blue 1997]], which, despite [https://en.wikipedia.org/wiki/Garry_Kasparov [Garry Kasparov]] lost the match, did result in a higher rating for him - 2754 versus 2741 for [[Deep Blue]].

* <span id="Impact"></span>[[Diogo R. Ferreira]] ('''2013'''). ''The Impact of the Search Depth on Chess Playing Strength''. [[ICGA Journal#36_2|ICGA Journal, Vol. 36, No. 2]] » [[Depth]], [[Depth#DiminishingReturns|Diminishing Returns]], [[Match Statistics]], [[Playing Strength]], [[Houdini]]<ref>[https://www.hiarcs.net/forums/viewtopic.php?t=10004 Ply versus ELO] by Greg, [[Computer Chess Forums|HIARCS Forum]], May 30, 2020</ref>