Chess (#977)

Professor Aprad Elo invented his rating system to normalise results across eras to compare players, who never met. Unfortunately, that is not possible. There is inflation as the pool of rated players grows.

Elo is, however, used to calculate everything from title awards to seeding and tie breaks. The rating difference predicts likely result (expectancy). For example, if a 2500 player meets a 2600 player, the 2600 should score about 61 per cent. The expectancy is 75:25 with a 200-point difference.

Fischer’s lifetime high, 2785, was the record until Garry Kasparov surpassed it. Only Kasparov, Kramnik, Anand, Topalov, Carlsen and Aronyan have ever crossed 2800 with Kasparov peaking at a record 2851 in July 1999. Judit Polgar, who peaked at 2735, is the only woman to cross 2700.

Tournament rating performances (TPR) of 2900-plus are quite rare. Magnus Carlsen’s recent victory at Bilbao was at a TPR of 2842. However, two 2900-plus TPRs have been recorded by women. In 1989, Zsofia Polgar (the middle Polgar sister) won the Rome Open, scoring 8.5 points from 9, with wins against six GMs. Zsofia was an untitled 14-year-old rated at 2295. Her TPR was 2930 against a field averaging 2503.

The other 2900 TPR is work-in-progress. At the Nalchik women’s GP, Zhao Xue leads with 9.5 points from 10 games. Her nearest rival in the 12-player round robin is Ju Wenjun, who has scored just 6, ensuring Xue's already won by a distance. At an average of 2506, Xue (seeded 8, Elo of 2497) is at a TPR of 2975.

Oddly, another 2900 TPR has just been recorded. Alexander Morozevich continued his fantastic run this year by winning the Saratov Governor’s Cup from a very strong field. Moro scored 8.5 from 11 in a 12-player RR. At the 2707 average, this is worth 2917. Evgeny Tomashevsky was second with 7, Leko third with 6, ahead of Alekseev, Shirov, Ponomariov, etc. Kramnik is also leading the Hoogeven RR with 3 points from 4 games and a TPR of 2905 but he needs 2/2 to stay 2900-plus.

The Diagram, WHITE TO PLAY, (Morozevich Vs Eljanov. Saratov 2011) was the setting for an incredible 34.Qc4!! Qd6 Black refused to enter 34.--Bxe1 35. d6+ Kh8 36. Nf7+ Kg8 37. d7! Bxf2+ 38. Kxf2 Rb8 39. d8=Q+ Rxd8 40. Nxd8+ Kh8 (40. - Kf8 41. Ne6+ Ke7 42. Nxc5) 41. Nf7+ Kg8 42. Ng5+ Kh8 43. Qe6! Qxe6 44. Nxe6 axb3 45. axb3. After this very deep combination, white must see he’s winning a materially inferior endgame, due to the stranded Kh8. White can pick up c5-d4 and push the b-pawn

Play continued 35.Re2 axb3 36.axb3 Ne7 37.Qb5 Bb4 38.Nc4 Qd8 39.d6 Nc6 40.Ne5 Nxe5 41.fxe5 (1–0).

Devangshu Datta is an internationally rated chess and correspondence chess player