2008 Beijing Olympic Games, Swimming Results by the Numbers:

Final Mathematical Analysis

The Olympic men’s swimming events were fast. Nine out of the 13 individual events recorded mean times for the eight finalists that were more than two standard deviations from the predicted values we generated based on previous performances at the Olympics dating back into the 1960s. In several cases the performances were in excess of 5 standard deviations of the projected mean. To put this in context, in the last Olympic Games, 2004 in Athens, the swimmers swam within our predicted range in all events. And, keep in mind, twenty-one world records were set in Beijing as compared to nearly one fifth that many in Athens. No men’s events were slower in 2008 when compared to 2004. The least different event was the 1500 m freestyle.

In the women’s events seven, a little more than half, were two standard deviations or more beyond our predicted values. Nearly all events were faster than in 2004 when compared to 2008 which was not true when the 2004 Games were compared with 2000 in Sydney. The single exception for the women is the 100 breaststroke as times were nearly identical to those recorded in 2004, being only a few hundredths of a second different.

The results of the swimming competition are, in general, exceptionally fast and do not fit the expectations of our mathematical modeling. It would appear that one or more bias has been introduced into the swim competition that did not play a role in determining the performances of the athletes until now. We would conclude that this bias has had a dominant role in enhancing performance in a manner inconsistent with the natural progression of swim performance that has been observed over the last half century.

Men's Events Analyisis

50 m freestyle
The 2008 Beijing Games’ average time for the top eight finalists for the men’s 50 freestyle was 21.57 seconds. This was fast, by any established measure at 4.08 standard deviations faster than our predicted mean time of 22.00 seconds. When compared with the previous 2004 Athens Olympic Games, the 2008 performances were, on average, 0.54 seconds faster (or 2.46%). The gold medalist, Cesar Cielo (21.30 sec, OR, Brazil), had not performed within our confidence interval prior to the Olympic Games and thus (in our opinion) was not expected to have a high probability of winning the gold medal. Both the silver and bronze medalists (silver; Amaury Leveaux, FRA, 21.45 sec; bronze; Alain Bernard, FRA, 21.49 sec) had previously performed within the window of probability we determined and thus were expected to be competitive for a medal. By comparison, the time improvement in swim performance in this event for the finalists between the 2000 and 2004 Games was 0.07 seconds or 0.33%.


100 m freestyle
The 2008 Beijing Olympic Games’ average time for the eight finalists for the men’s 100 freestyle was 47.77 seconds. This average time was 5.38 standard deviations faster than our predicted time of 48.79 seconds and much faster than the expected. When compared to the performances at the previous 2004 Athens Olympic Games, the swimmers at the 2008 Games were, on average, 1.03 seconds faster (2.11%). Three of the four medalists (there was a tie for bronze) had previously swum within our confidence interval with the exception being Cielo. ( Gold: Alain Bernard, FRA, 47.21 sec, Silver: Eamon Sullivan, AUS, 47.32 sec, Bronze: Jason Lezak, USA; Cesar Cielo, BRA, 47.67sec). By comparison, the time improvement in swim performance in this event for the finalists between the 2000 and 2004 Games was 0.14 sec or 0.30%.

200 Freestyle
The 2008 Olympic Games’ average time for the eight finalists of the men’s 200 freestyle was 1:45.81 seconds. This time was 1.25 standard deviations faster than our predicted time of 1:46.61 seconds. When compared with the previous 2004 Athens Olympic Games, the final heat of swimmers in 2008 were, on average, 0.68 seconds faster. Phelps (gold: 1:42.96 sec) and Vanderkaay (bronze: 1:45.14 sec) were expected to contend and had performed within the established confidence interval but South Korea’s Park (silver: 1:44.85 sec) had not. By comparison, the time improvement in swim performance in this event for the finalists between the 2000 and 2004 Games was 0.94 sec or 0.88%.

400 meter Freestyle
The 2008 Beijing Olympic Games’ average time for the eight finalists in the men’s 400 freestyle was 3:43.72 seconds. This was 1.11 standard deviations faster than our predicted time of 3:45.09 seconds. When compared with the previous 2004 Olympic Games, 2008 the finalists were, on average, 2.20 seconds faster. None of the medalists (Gold: Taehwan Park, KOR, 3:41.86 sec; Silver: Lin Zhang, CHN, 3:42.44 sec) had previously performed within our established confidence interval although Larsen Jensen (bronze: 3:42.78 sec AR) finished fourth in this event in Athens. We should note here that not “all previous performances” may be available in the public domain. It is an assumption, on our part, that we are able to obtain all performances on record worldwide. By comparison, the time improvement in swim performance in this event for the finalists between the 2000 and 2004 Games was 0.30 sec or 0.13%.

1500 m freestyle
The 2008 Beijing Olympic Games’ average time for the eight finalists of the men’s 1500 m freestyle was 14:48.61 seconds. This was 0.76 standard deviations faster than our predicted mean time of 14:54.18 seconds. When compared with the previous Olympic Games, 2008teh performances were, on average, 9.44 seconds faster. Hackett (Silver: AUS, 14:41.53 sec) was predicted to be the lone contender and finished with a silver medal. Mellouli (gold TUN, 14:40.84 sec) and Cochrane (bronze, CAN, 14:42.69 sec) were not previously known to have performed within our confidence interval. By comparison, the time improvement in swim performance in this event for the finalists between the 2000 and 2004 Games was 3.62 sec or 0.40%.

100 m Backstroke
The 2008 Beijing Olympic Games’ average time for the men’s eight finalists in the 100 backstroke was 53.28 seconds. This was 3.21 standard deviations faster than our predicted time of 54.50 seconds. When compared with the previous 2004 Athens Olympic Games, 2008 was, on average, 1.24 seconds faster. All three medalists (Gold: Aaron Peirsol, USA, 52.54; Silver: Matt Grevers, USA, 53.11; Bronze: Arkady Vyatchanin, RUS and Hayden Stoeckel, AUS, 53.18) were predicted to contend for medals. By comparison, the time improvement in swim performance in this event for the finalists between the 2000 and 2004 Games was 0.33 sec or 0.60%.

200 m Backstroke
The 2008 Beijing Olympic Games’ average time for the eight men’s finalists in the 200 backstroke was1:55.54 seconds. This time was 3.22 standard deviations faster than our predicted average time of 1:58.31 seconds. When compared with the previous Olympic Games, the swimmers in 2008 were, on average, 2.44 seconds faster. All three medalists were predicted to contend. (Gold: Ryan Lochte, USA, 1:53.94 sec,(WR), Silver: Aaron Peirsol, USA, 1:54.33 sec, Bronze: Arkady Vyatchanin, 1:54.93 sec). By comparison, the time improvement in swim performance in this event for the finalists between the 2000 and 2004 Games was 0.44 sec or 0.38 %.

100 m breastroke
The 2008 Beijing Olympic average time for the eight men’s finalists in the 100 breaststroke was 59.64 seconds. This was 4.70 standard deviations faster than our predicted time of 1:00.91 seconds. When compared with the previous Olympic Games, 2008 was, on average, 1.51 seconds faster. All three medalists were expected to contend. (Gold: Kosuke Kitajima, JPN, 58.91 sec, Silver: Dael Oen, NOR, 59.20 sec, Bronze: Hugues DuBoscq, FRA, 59.37 sec). By comparison, the time improvement in swim performance in this event for the finalists between the 2000 and 2004 Games was 0.11 sec or 0.18%.

200 m breastroke
The 2008 Beijing Olympic average time for the eight men’s finalists in the 200 breaststroke was 2:09.44 seconds. This was 2.13 standard deviations faster than our predicted time of 2:11.34 seconds. When compared with the previous 2004 Athens Olympic Games, 2008 was, on average, 1.70 seconds faster. Kitajima was predicted to be the lone contender and finished with gold. Rickard (silver) and Dubosq (bronze) were not previously within our confidence interval. (Gold: Kosuke Kitajima, JPN, 2:07.64 sec (OR), Silver: Brenton Rickard, AUS, 2:08.88 sec, Bronze: Hugues DuBoscq, FRA, 2:08.94 sec). By comparison, the time improvement in swim performance in this event for the finalists between the 2000 and 2004 Games was 1.71 sec or 1.29%.

100 m butterfly
The 2008 Beijing Olympic average time for the eight men’s finalists in the 100 butterfly was 51.23 seconds. This was 3.03 standard deviations faster than our predicted time of 52.38 seconds. When compared with the previous Olympic Games, 2008 was, on average, 0.75 seconds faster. Cavic (silver, SRB, 50.59 sec) was not previously within our confidence interval. (Gold: Michael Phelps, USA, 50.58 sec (OR), Bronze: Andrew Lauterstein, AUS, 51.12 sec). By comparison, the time improvement in swim performance in this event for the finalists between the 2000 and 2004 Games was 0.55 sec or 1.05%.

200 m butterfly
The 2008 Beijing Olympic average time for the eight men’s finalists 200 butterfly was 1:53.86 seconds. This was 3.21 standard deviations faster than our predicted time of 1:56.33 seconds. When compared with the previous Olympic Games, 2008 was, on average, 2.03 seconds faster. Lazslo Cseh (silver) was not previously within our confidence interval. (Gold: Michael Phelps, USA, 1:52.03 sec (WR), Silver: Laszlo Cseh, HUN, 1:52.70 sec, Bronze: Takeshi Matsuda, JPN, 1:52.97 sec. By comparison, the time improvement in swim performance in this event for the finalists between the 2000 and 2004 Games was 0.08 sec or 0.68%.

200 m Individual Medley
The 2008 Beijing Olympic average time for the eight men’s finalists in the 200 individual medley was 1:57.88 seconds. This was 4.55 standard deviations faster than our predicted time of 2:00.02 seconds. When compared with the previous Olympic Games, 2008 was, on average, 1.83 seconds faster. All three medalists were expected to contend (Gold: Michael Phelps, USA, 1:54.23 sec, (WR), Silver: Laszlo Cseh, HUN, 1:56.52 sec, Bronze: Ryan Lochte, USA, 1:56.53). By comparison, the time improvement in swim performance in this event for the finalists between the 2000 and 2004 Games was 1.41 sec or 1.17%.

400 m Individual Medley
The 2008 Beijing Olympic average time for the eight men’s finalists in the 400 individual medley was 4:10.54 seconds. This was 5.23 standard deviations faster than our predicted time of 4:13.99 seconds. When compared with the previous 2004 Olympic Games, finalists in the 2008 Games were, on average, 4.17 seconds faster. All three medalists were expected to contend (Gold: Michael Phelps, USA, 4:03.84 (WR), Silver: Laszlo Cseh, HUN, 4:06.16, Bronze: Ryan Lochte, USA, 4:08.09). By comparison, the time improvement in swim performance in this event for the finalists between the 2000 and 2004 Games was 2.03 sec or 0.79%.


Women’s Events Analysis

50 m freestyle
The 2008 Beijing Olympic Games’ average time for the eight finalists in the women’s 50 m freestyle was 24.36 seconds. This was 4.78 standard deviations faster than our predicted time of 24.79 seconds. When compared with the previous 2004 Athens Olympic Games, 2008 was, on average, 0.60 seconds faster. All three medalists (Gold: Britta Steffen, GER, 24.06 sec (OR); Silver: Dara Torres, USA, 24.07 sec (AR); Bronze: Cate Campbell, AUS, 24.17 sec) were expected to contend by our estimates. By comparison, the time improvement in swim performance in this event for the finalists between the 2000 and 2004 Games was 0.05 sec or 0.21%.

100 m freestyle
The 2008 Beijing Olympic Games’ average time for the eight finalists in the women’s 100 freestyle was 53.80 seconds. This was 2.20 standard deviations faster than our predicted time of 54.46 seconds. When compared with the previous Olympic Games, 2008 was, on average, 0.78 seconds faster. All three medalists (Gold: Britta Steffen, GER, 53.12 sec (OR); Silver: Libby Trickett, AUS, 53.16 sec; Bronze: Natalie Coughlin, USA, 53.39 sec (AR) ) were expected to contend. By comparison, the time improvement in swim performance in this event for the finalists between the 2000 and 2004 Games was 0.18 sec or 0.33%.

200 m freestyle
The 2008 Beijing Olympic Games’ average time for the eight finalists in the women’s 200 freestyle was 1:56.35 seconds. This was 2.98 standard deviations faster than our predicted time of 1:58.08 seconds. When compared with the previous Olympic Games, 2008 was, on average, 2.34 seconds faster. Isakovic (silver) and Pang (bronze) were not previously within our confidence interval. (Gold: Federica Pellegrini, ITA, 1:54.82 sec. (WR) Silver: Sara Isakovic, SLO, 1:54.97 sec; Bronze: Jiaying Pang, CHN, 1:55.05 sec.) By comparison, the time improvement in swim performance in this event for the finalists between the 2000 and 2004 Games was 0.23 sec or 0.19%.

400 m freestyle
The 2008 Beijing Olympic Games’ average time for the eight finalists in the women’s 400 freestyle was 4:04.90 seconds. This was 1.28 standard deviations faster than our predicted time of 4:07.02 seconds. When compared with the previous Olympic Games, the 2008 finalists were, on average, 3.15 seconds faster. Adlington (gold, GBR, 4:03.22 sec) and Jackson (bronze, GBR, 4:03.52 sec) were not previously within our confidence interval. Silver: Katie Hoff, USA, 4:03.29 sec, however, was. By comparison, the time improvement in swim performance in this event for the finalists between the Sydney 2000 and Athens 2004 Games was 1.41 sec or 0.57%.

800 m freestyle
This year’s average of the women’s 800 freestyle was 8:24.42 seconds. This was 0.46 standard deviations faster than our predicted time of 8:25.93 seconds. When compared with the previous Olympic Games, 2008 was, on average, 4.64 seconds faster. Fris (bronze) was not previously within our confidence interval. Gold: Rebecca Adlington, GBR, 8:14.10 sec (WR) and Silver: Alessia Filippi, ITA, 8:20.23 sec, however, were.
By comparison, the time decrease in swim performance in this event for the finalists between the 2000 and 2004 Games was (actually negative or slower than 2000) -1.24 sec or -0.24%.

100 m backstroke
The 2008 Beijing Olympic Games’ average time for the eight finalists in the women’s 100 backstroke was 59.53 seconds. This was 3.83 standard deviations faster than our predicted time of 1:00.87 seconds. When compared with the previous Olympic Games, 2008 was, on average, 1.54 seconds faster. All three medalists (Gold: Natalie Coughlin, USA, 58.96 sec; Silver: Kirsty Coventry, ZIM, 59.19 sec; and Bronze: Margaret Hoelzer, USA, 59.34) were expected to contend. By comparison, the time improvement in swim performance in this event for the finalists between the 2000 and 2004 Games was 0.05 sec or 0.08%.

200 m backstroke
The 2008 Beijing Olympic Games’ average time for the eight finalists in the women’s 200 backstroke was 2:07.77 seconds. This was 2.10 standard deviations faster than our predicted time of 2:09.91 seconds. When compared with the previous Olympic Games, 2008 was, on average, 2.92 seconds faster. Nakamura (bronze; JPN, 2:07.13 sec) was not previously within our confidence interval. Gold: Kirsty Coventry, ZIM, 2:05.24 sec (WR) and Silver: Margaret Hoelzer, USA, 2:06.23 were supposed to contend. By comparison, the time improvement in swim performance in this event for the finalists between the 2000 and 2004 Games was 1.02 sec or 0.77%.

100 m breastroke
The 2008 Beijing Olympic Games’ average time for the eight finalists in the women’s 100 breaststroke was 1:07.30 seconds. This was 0.06 standard deviations faster than our predicted time of 1:07.32 seconds. When compared with the previous Olympic Games, 2008 was, on average, 0.09 seconds faster. Soni (silver; USA, 1:06.73 sec) and Jukic (bronze; AUT, 1:07.34) were not previously within our confidence interval. Gold: Leisel Jones, AUS, 1:05.17 however, was. By comparison, the time improvement in swim performance in this event for the finalists between the 2000 and 2004 Games was 0.78 sec or 1.15%.

200 m breastroke
The 2008 Beijing Olympic Games’ average time for the eight finalists in the women’s 200 breaststroke was 2:23.30 seconds. This was 1.44 standard deviations faster than our predicted time of 2:24.51 seconds. When compared with the previous Olympic Games, 2008 was, on average, 2.19 seconds faster. Nordenstam (bronze, NOR, 2:23.02 sec) was not previously within our confidence interval. Gold: Rebecca Soni, USA, 2:20.22 sec (WR) and Silver: Leisel Jones AUS, 2:22.05 sec, however, were. By comparison, the time improvement in swim performance in this event for the finalists between the 2000 and 2004 Games was 0.15 sec or 0.11%.

100 m butterfly
The 2008 Beijing Olympic Games’ average time for the eight finalists in the women’s 100 butterfly was 57.70 seconds. This was 1.81 standard deviations faster than our predicted time of 58.57 seconds. When compared with the previous Olympic Games, 2008 was, on average, 0.84 seconds faster. All three medalists (Gold: Lisbeth Trickett, AUS, 56.73 sec; Silver: Christine Magnuson, USA, 57.10 sec. Bronze: Jessica Schipper, AUS, 57.25 sec were expected to contend. By comparison, the time improvement in swim performance in this event for the finalists between the 2000 and 2004 Games was - 0.06 sec or -0.11% ( slower than 2000).

200 m butterfly
The 2008 Beijing Olympic Games’ average time for the eight finalists in the women’s 200 butterfly was 2:06.58 seconds. This was 2.21 standard deviations faster than our predicted time of 2:08.15 seconds. When compared with the previous Olympic Games, 2008 was, on average, 2.00 seconds faster. Liu (gold, CHN, 2:04.18 sec (WR)) and Jiao (silver, CHN, 2:04.72 sec) were not previously within our confidence interval. Bronze: Jessicah Schipper, AUS, 2:06.26, however, was. By comparison, the time improvement in swim performance in this event for the finalists between the 2000 and 2004 Games was 0.39 sec or 0.31% (slower than 2000).

200 m Individual Medley
The 2008 Beijing Olympic Games’ average time for the eight finalists in the women’s 200 individual medley was 2:10.86 seconds. This was 4.48 standard deviations faster than our predicted time of 2:12.74 seconds. When compared with the previous Olympic Games, 2008 was, on average, 2.38 seconds faster. All three medalists were expected to contend (Gold: Stephanie Rice, AUS, 2:08.45 (WR), Silver: Kirsty Coventry, ZIM, 2:08.59 sec, Bronze: Natalie Coughlin, USA, 2:10.34 sec). By comparison, the time improvement in swim performance in this event for the finalists between the 2000 and 2004 Games was 0.26 sec or 0.20%.

400 m Individual medley
The 2008 Beijing Olympic Games’ average time for the eight finalists in the women’s 400 individual medley was 4:35.16 seconds. This was 1.14 standard deviations faster than our predicted time of 4:37.97 seconds. When compared with the previous Olympic Games, 2008 was, on average, 5.84 seconds faster. Coventry (silver; ZIM, 4:29.89 sec) was not previously within our confidence interval. Gold: Stephanie Rice, AUS, 4:29.45 sec (WR) and Bronze: Katie Hoff, USA, 4:31.71sec, however, were. By comparison, the time improvement in swim performance in this event for the finalists between the 2000 and 2004 Games was -0.16 sec or 0.06%.