Olympic Odds: Each Swimmer’s Probability Of Winning Gold In Tokyo

by SwimSwam 151

February 24th, 2020 International, Tokyo 2020

By Daniel Takata Gomes

In this article, we present each swimmer’s chances of winning the gold medal at the Tokyo Olympic Games.

Statistical methods based on computational simulations were used in order to estimate the probability of winning the gold medal for each swimmer. Results from 2018 were considered in the calculations. The more recent the result is, more impact it has in the probabilities.

The method was determined by observing results from 2014 to 2016 and comparing them to what in fact occurred at the 2016 Olympics, in order to find the most suitable probability distribution.

Some remarks: Adam Peaty has a 97.09% chance of winning the 100 breast. Caeleb Dressel, 93.24% in the 100 fly. Regan Smith, 86.43% in the 200 back. Kristof Milak, 83.54% in the 200 fly. Katie Ledecky, 72.3% in the 800 and 1500 free.

The most disputed races are the women’s 100 free (Simone Manuel 35.48%, Cate Campbell 33.34% and Sarah Sjostrom 21.96%) and the men’s 1500 free (Florian Wellbrock 31.31%, Gregorio Paltrinieri 30.81% and Mykhailo Romanchuk 25.99%).

Of course, these probabilities will change, depending on how swimmers will swim until the Olympics. The probabilities will be updated on a regular basis.

METHODOLOGY EXPLAINED

The approach here is to determine the probabilities in an empirical fashion. If you have a coin and you don’t know the chances of tails and heads, you can toss the coin, let’s say, 1,000 times. If you get 512 tails and 488 heads, the estimated probabilities are 51.2% and 48.8%, respectively.

So we don’t know what’s the chance of, let’s say, Simone Manuel winning the 50 freestyle. Manuel could swim the event 1,000 times, as well as her adversaries, and we could count how many times she would win to estimate her winning probability. Obviously this can’t be done. In this situation, we simulate the possible outcomes in a computer program using a statistical method.

How do we do that? Let’s go back to 2016. Manuel arrived in Rio with a 24.33 from the US Olympic Trials. In Rio, she managed to a 24.09. Cate Campbell came in with a 23.84, and in Rio, she went 24.15. And so on. I conducted the calculations and realized that, comparing to the times registered from 2014 until the Olympics, the times of the top swimmers in the Olympics present a specific pattern of variability, well explained by the so-called normal distribution of probability.

Using the very same pattern of variability, it is possible to simulate the possible outcomes for Tokyo. Manuel has a 23.97 from 2019. So, her time for Tokyo is simulated according to that pattern of variability. In 1,000 trials, let’s say that her simulated times are 24.08, 23.90, 24.18, 24.01, 23.79, 23.89, etc. Her times will float around 23.97 with some variability. We do the same for every other swimmer. Let’s say that, in 1,000 trials, Manuel has the best time of all swimmers in 800, so she has an 8% chance of winning.

The same procedure was conducted in all events, according to the respective pattern of variation. In relays, the sum of the times of the fastest swimmers of each country in each round of simulation was considered.

CURRENT PROBABILITIES

Women’s events

50m freestyle

  1. Sarah Sjostrom (SWE) – 52.31%
  2. Cate Campbell (AUS) – 25.15%
  3. Pernille Blume (DEN) – 9.87%
  4. Simone Manuel (USA) – 8.49%
  5. Liu Xiang (CHN) – 2.32%
  6. Bronte Campbell (AUS) – 0.58%
  7. Emma McKeon (AUS) – 0.48%
  8. Ranomi Kromowidjojo (NED) – 0.30%

100m freestyle

  1. Simone Manuel (USA) – 35.48%
  2. Cate Campbell (AUS) – 33.34%
  3. Sarah Sjostrom (SWE) – 21.96%
  4. Emma McKeon (AUS) – 5.58%
  5. Bronte Campbell (AUS) – 1.86%
  6. Taylor Ruck (CAN) – 0.34%
  7. Pernille Blume (DEN) – 0.24%
  8. Mallory Comerford (USA) – 0.17%

200m freestyle

  1. Federica Pellegrini (ITA) – 33.65%
  2. Ariarne Titmus (AUS) – 23.77%
  3. Sarah Sjostrom (SWE) – 16.55%
  4. Emma McKeon (AUS) – 10.97%
  5. Katie Ledecky (USA) – 4.16%
  6. Siobhan Haughey (HKG) – 3.59%
  7. Yang Junxuan (CHN) – 2.83%
  8. Charlotte Bonnet (FRA) – 1.09%

400m freestyle

  1. Katie Ledecky (USA) – 51.43%
  2. Ariarne Titmus (AUS) – 34.51%
  3. Leah Smith (USA) – 10.25%
  4. Ajna Kesely (HUN) – 2.62%
  5. Wang Jianjiahe (CHN) – 0.41%
  6. Li Bingjie (CHN) – 0.39%
  7. Katinka Hosszu (HUN) – 0.11%
  8. Simona Quadarella (ITA) – 0.09%

800m freestyle

  1. Katie Ledecky (USA) – 72.30%
  2. Simona Quadarella (ITA) – 9.45%
  3. Ariarne Titmus (AUS) – 7.71%
  4. Wang Jianjiahe (CHN) – 4.54%
  5. Leah Smith (USA) – 3.66%
  6. Sarah Koehler (GER) – 1.95%
  7. Kiah Melverton (AUS) – 0.11%
  8. Mireia Belmonte (ESP) – 0.08%

1500m freestyle

  1. Katie Ledecky (USA) – 72.25%
  2. Simona Quadarella (ITA) – 16.21%
  3. Wang Jianjiahe (CHN) – 5.96%
  4. Sarah Koehler (GER) – 3.37%
  5. Delfina Pignatiello (ARG) – 0.75%
  6. Erica Sullivan (USA) – 0.30%
  7. Ashley Twichell (USA) – 0.29%
  8. Ajna Kesely (HUN) – 0.27%

100m backstroke

  1. Regan Smith (USA) – 47.14%
  2. Kylie Masse (CAN) – 30.49%
  3. Minna Atherton (AUS) – 5.81%
  4. Kathleen Baker (USA) – 5.26%
  5. Olivia Smoliga (USA) – 4.25%
  6. Taylor Ruck (CAN) – 2.67%
  7. Phoebe Bacon (USA) – 1.79%
  8. Emily Seebohm (AUS) – 0.89%

200m backstroke

  1. Regan Smith (USA) – 86.43%
  2. Kylie Masse (CAN) – 6.75%
  3. Kaylee McKeown (AUS) – 2.76%
  4. Margherita Panziera (ITA) – 2.26%
  5. Taylor Ruck (CAN) – 0.51%
  6. Katinka Hosszu (HUN) – 0.41%
  7. Minna Atherton (AUS) – 0.40%
  8. Kathleen Baker (USA) – 0.27%

100m breaststroke

  1. Lilly King (USA) – 60.06%
  2. Yuliya Efimova (RUS) – 34.23%
  3. Reona Aoki (JPN) – 1.18%
  4. Martina Carraro (ITA) – 1.17%
  5. Annie Lazor (USA) – 1.01%
  6. Tatjana Schoenmaker (RSA) – 0.43%
  7. Arianna Castiglioni (ITA) – 0.23%
  8. Molly Hannis (USA) – 0.22%

200m breaststroke

  1. Yuliya Efimova (RUS) – 57.62%
  2. Annie Lazor (USA) – 10.62%
  3. Lilly King (USA) – 7.54%
  4. Evgeniia Chikunova (RUS) – 7.52%
  5. Tatjana Schoenmaker (RSA) – 7.07%
  6. Bethany Galat (USA) – 2.57%
  7. Sydney Pickrem (CAN) – 2.27%
  8. Emily Escobedo (USA) – 1.72%

100m butterfly

  1. Maggie Macneil (CAN) – 61.83%
  2. Sarah Sjostrom (SWE) – 25.98%
  3. Emma McKeon (AUS) – 9.02%
  4. Kelsi Worrell (USA) – 1.43%
  5. Marie Wattel (FRA) – 0.39%
  6. Elena Di Liddo (ITA) – 0.35%
  7. Brianna Throssell (AUS) – 0.26%
  8. Louise Hansson (SWE) – 0.22%

200m butterfly

  1. Hali Flickinger (USA) – 31.15%
  2. Boglarka Kapas (HUN) – 16.06%
  3. Katherine Drabot (USA) – 13.79%
  4. Katinka Hosszu (HUN) – 8.70%
  5. Alys Margaret Thomas (GBR) – 7.65%
  6. Franziska Hentke (GER) – 4.06%
  7. Zhang Yufei (CHN) – 2.70%
  8. Regan Smith (USA) – 1.88%

200m ind. medley

  1. Katinka Hosszu (HUN) – 52.63%
  2. Shiho Matsumoto (JPN) – 26.10%
  3. Ye Shiwen (CHN) – 7.50%
  4. Sydney Pickrem (CAN) – 5.33%
  5. Yui Ohashi (JPN) – 3.00%
  6. Rika Omoyo (JPN) – 1.77%
  7. Melanie Margalis (USA) – 1.11%
  8. Alex Walsh (USA) – 0.93%

400m ind. medley

  1. Katinka Hosszu (HUN) – 47.47%
  2. Ye Shiwen (CHN) – 21.10%
  3. Yui Ohashi (JPN) – 18.76%
  4. Shiho Matsumoto (JPN) – 8.62%
  5. Mireia Belmonte (ESP) – 1.60%
  6. Emma Weyant (USA) – 0.48%
  7. Sydney Pickrem (CAN) – 0.47%
  8. Brooke Forde (USA) – 0.29%

4x100m freestyle relay

  1. Australia – 63.87%
  2. United States – 35.24%
  3. Canada – 0.47%
  4. France – 0.17%
  5. Netherlands – 0.08%
  6. Great Britain – 0.05%
  7. Japan – 0.04%
  8. China – 0.04%

4x200m freestyle relay

  1. Australia – 48.16%
  2. United States – 37.67%
  3. China – 8.91%
  4. Canada – 3.02%
  5. Japan – 1.09%
  6. Russia – 0.56%
  7. Italy – 0.40%
  8. Great Britain – 0.08%

4x100m medley relay

  1. United States – 80.31%
  2. Australia – 9.78%
  3. Canada – 8.48%
  4. Russia – 0.67%
  5. Italy – 0.32%
  6. Japan – 0.32%
  7. Sweden – 0.06%
  8. Great Britain – 0.03%

Men’s events

50m freestyle

  1. Caeleb Dressel (USA) – 68.38%
  2. Bruno Fratus (BRA) – 11.76%
  3. Vladimir Morozov (RUS) – 7.41%
  4. Benjamin Proud (GBR) – 6.02%
  5. Kristian Gkolomeev (GRE) – 3.63%
  6. Andrea Vergani (ITA) – 1.22%
  7. Florent Manaudou (FRA) – 0.68%
  8. Michael Andrew (USA) – 0.45%

100m freestyle

  1. Caeleb Dressel (USA) – 41.03%
  2. Kyle Chalmers (AUS) – 39.59%
  3. Vladislav Grinev (RUS) – 8.56%
  4. Ryan Held (USA) – 4.47%
  5. Maxime Rooney (USA) – 1.53%
  6. Marcelo Chierighini (BRA) – 1.20%
  7. Zach Apple (USA) – 1.04%
  8. Vladimir Morozov (RUS) – 0.42%

200m freestyle

  1. Danas Rapsys (LTU) – 33.37%
  2. Duncan Scott (GBR) – 16.10%
  3. Sun Yang (CHN) – 10.85%
  4. Katsuhiro Matsumoto (JPN) – 9.47%
  5. Clyde Lewis (AUS) – 6.81%
  6. Martin Malyutin (RUS) – 6.18%
  7. Kyle Chalmers (AUS) – 2.73%
  8. Ji Xinjie (CHN) – 2.30%

400m freestyle

  1. Sun Yang (CHN) – 37.10%
  2. Mack Horton (AUS) – 24.04%
  3. Gabriele Detti (ITA) – 22.41%
  4. Danas Rapsys (LTU) – 5.99%
  5. Jack McLoughlin (AUS) – 2.64%
  6. Elijah Winnington (AUS) – 1.69%
  7. Marco De Tullio (ITA) – 1.61%
  8. Alexander Krasnykh (RUS) – 0.68%

800m freestyle

  1. Gregorio Paltrinieri (ITA) – 45.87%
  2. Henrik Christiansen (NOR) – 17.98%
  3. Gabriele Detti (ITA) – 10.65%
  4. David Aubry (FRA) – 5.74%
  5. Mykhailo Romanchuk (UCR) – 4.60%
  6. Jack McLoughlin (AUS) – 4.46%
  7. Florian Wellbrock (GER) – 3.62%
  8. Sun Yang (CHN) – 2.84%

1500m freestyle

  1. Florian Wellbrock (GER) – 31.31%
  2. Gregorio Paltrinieri (ITA) – 30.81%
  3. Mykhaulo Romanchuk (UKR) – 25.99%
  4. David Aubry (FRA) – 2.27%
  5. Henrik Christiansen (NOR) – 2.05%
  6. Franko Grgic (CRO) – 1.45%
  7. Daniel Jervis (GBR) – 1.39%
  8. Alexander Norgaard (DEN) – 1.03%

100m backstroke

  1. Evgeny Rylov (RUS) – 43.43%
  2. Xu Jiayu (CHN) – 25.59%
  3. Mitchell Larkin (AUS) – 14.28%
  4. Ryan Murphy (USA) – 11.86%
  5. Matt Grevers (USA) – 1.81%
  6. Ryosuke Irie (JPN) – 0.86%
  7. Shaine Casas (USA) – 0.79%
  8. Kliment Kolesnikov (RUS) – 0.73%

200m backstroke

  1. Evgeny Rylov (RUS) – 54.55%
  2. Ryan Murphy (USA) – 33.90%
  3. Xu Jiayu (CHN) – 5.41%
  4. Mitchell Larkin (AUS) – 2.57%
  5. Ryosuke Irie (JPN) – 1.03%
  6. Luke Greenbank (GBR) – 0.98%
  7. Austin Katz (USA) – 0.35%
  8. Keita Sunama (JPN) – 0.24%

100m breaststroke

  1. Adam Peaty (GBR) – 97.09%
  2. James Wilby (GBR) – 1.02%
  3. Ilya Shymanovich (BLR) – 0.70%
  4. Yan Zibei (CHN) – 0.56%
  5. Arno Kamminga (NED) – 0.22%
  6. Anton Chupkov (RUS) – 0.11%
  7. Nicolo Martinenghi (ITA) – 0.08%
  8. Yasuhiro Koseki (JPN) – 0.05%

200m breaststroke

1. Anton Chupkov (RUS) – 46.71%
2. Matthew Wilson (AUS) – 17.69%
3. Ippei Watanabe (JPN) – 16.62%
4. Zac Stubblety-Cook (AUS) – 3.40%
5. James Wilby (GBR) – 2.04%
6. Marco Koch (GER) – 1.87%
7. Will Licon (USA) – 1.61%
8. Josh Prenot (USA) – 1.39%

100m butterfly

  1. Caeleb Dressel (USA) – 93.24%
  2. Chad Le Clos (RSA) – 2.09%
  3. Andrei Minakov (RUS) – 1.79%
  4. Maxime Rooney (USA) – 1.33%
  5. Mehdy Metella (FRA) – 0.54%
  6. Kristof Milak (HUN) – 0.25%
  7. Jack Conger (USA) – 0.15%
  8. Grant Irvine (AUS) – 0.12%

200m butterfly

  1. Kristof Milak (HUN) – 83.54%
  2. Daiya Seto (JPN) – 13.54%
  3. Tamas Kenderesi (HUN) – 1.32%
  4. Chad Le Clos (RSA) – 1.00%
  5. Luca Urlando (USA) – 0.41%
  6. Nao Horomura (JPN) – 0.06%
  7. Federico Burdisso (ITA) – 0.05%
  8. Denys Kesyl (UKR) – 0.04%

200m ind. medley

  1. Daiya Seto (JPN) – 41.24%
  2. Chase Kalisz (USA) – 19.81%
  3. Mitchell Larkin (AUS) – 15.77%
  4. Wang Shun (CHN) – 7.88%
  5. Jeremy Desplanches (SUI) – 6.61%
  6. Duncan Scott (GBR) – 2.21%
  7. Philip Heintz (GER) – 1.88%
  8. Qin Haiyang (CHN) – 1.73%

400m ind. medley

  1. Daiya Seto (JPN) – 53.21%
  2. Jay Litherland (USA) – 19.05%
  3. Wang Shun (CHN) – 7.04%
  4. Chase Kalisz (USA) – 5.24%
  5. Qin Haiyang (CHN) – 3.80%
  6. Lewis Clareburt (NZL) – 2.55%
  7. Max Litchfield (GBR) – 2.12%
  8. David Verraszto (HUN) – 1.59%

4x100m freestyle relay

  1. United States – 86.00%
  2. Russia – 7.48%
  3. Australia – 4.04%
  4. Brazil – 1.75%
  5. Italy – 0.24%
  6. Japan – 0.23%
  7. Great Britain – 0.13%
  8. China – 0.05%

4x200m freestyle relay

  1. Australia – 43.47%
  2. United States – 27.87%
  3. Russia – 17.77%
  4. Great Britain – 5.69%
  5. China – 4.27%
  6. Brazil – 0.54%
  7. Japan – 0.25%
  8. Italy – 0.09%

4x100m medley relay

  1. United States – 76.70%
  2. Russia – 12.77%
  3. Australia – 3.74%
  4. Great Britain – 3.50%
  5. China – 1.26%
  6. Japan – 1.08%
  7. Italy – 0.47%
  8. Brazil – 0.46%

Mixed Events

4x100m medley relay

  1. United States – 86.61%
  2. Australia – 8.25%
  3. Great Britain – 2.71%
  4. Russia – 1.22%
  5. China – 0.37%
  6. Italy – 0.27%
  7. Japan – 0.27%
  8. Canada – 0.19%

You can keep up to date with the probabilities here.

About Daniel Takata Gomes

Daniel Takata is editor of Swim Channel Magazine from Brazil, has a PhD in Statistics and is a college professor. He also works as a swimming TV commentator on SporTV and holds a website dedicated to sports analytics, Esportístico (www.esportistico.com.br).

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Swimdood

Really fun article!

AuggieBuschFan

I think the biggest eh in this is the Katie Ledecky 200m free chances…..

Silver at worlds in 2017, no medals in 2019 (sick at Worlds in 2019 of course), bronze at Pan Pacs in 2018. Hasn’t been a 1:53 since Rio.

I do think it’s a little low, but not egregiously so. The two biggest factors that I think the data doesn’t account for:

1) Being sick at Worlds in 2019
2) I don’t think Sjostrom will race it in Tokyo.

So, pull out those two things, and you probably see her bump up to 15-20%, which sounds about right to me.

All this to say, if a bookmaker were laying 4.16% (which is the implied probability of about 21/1 payout), I would put money on that all day.

AuggieBuschFan

Agreed!

Yozhik

Not being 1:53 since Rio. What kind of argument is that. It is the same as saying that Katie wasn’t under 8:05 since Rio. People may not understand that 1:53.61 of Allison Schmitt in London Olympics and 1:53.73 of Katie Ledecky in Rio Olympics are outstanding and the only under 1:54 results in the history of this event. That they were achieved by unique swimmers at the best by far seasons of their careers. Nobody will repeat that in Tokyo.

AuggieBuschFan

I mean I see your point but at the end of the day Ledecky has way more competition in the 200 free than the 800 free… She could go 1:53 and lose to Sjostrom or Federica. But if she goes 8:05 shes not gonna lose…. That’s not opinion that’s fact. Sjostrom has been 1:54.0 and Federica has been 1:52. Obviously in 2009 but has still been 1:54 low since. Ledecky goes 1:53 one time 4 years ago (only beating Sjostrom by .3 btw) and you think all these 1:54s which have happened recently dont matter. fool.

Yozhik

I won’t argue with you because neither you nor me know what will happen in Tokyo. But I’m ready to bet that nobody will go under 1:54. Even more, i’m ready to bet that neither Sjostrom nor Pellegrini nor Titmus nor McKeon nor Ledecky will beat their personal best. Who of them will win gold medal depends on many factors. That is the race if you understand what it means.

AuggieBuschFan

I appreciate your strong sense of wisdom and understanding here to mediate the discussion, very enlightening

Jeff

I don’t think it’s even guaranteed to be one of them 5. So many other names in the mix that we can’t rule out yet – Ruck, Haughey, Yang, Anderson(if she can improve enough) – the point is that it will literally depend on who turns up in the best form on that final of the 200 free.

swimfast

i think the women’s 200 free is simply a wide open event generally speaking. i know this is a statistical odds analysis; but as a swim fan i’ll more unofficially say it’s equal odds for all the favorites. a 1:53.5 could as easily win as a 1:55.0, right? i wouldn’t be shocked if either of those times is the winner, and any of these ladies are sincerely capable of those times. it’s just going to be a dog fight, and ledecky is no less likely, in my mind, to win or lose than any of the other girls

YOZHIK, who is more qualified than anyone on earth to make predictions, is calling his shot: 1:54 wins the 200 free in Tokyo.

Book it.

Yozhik

I like it when you type Yozhik in upper case and the Earth in low case. It makes me feel Universely significant 😀 But if you intelligence got offended I am ready to listen who of active swimmers are of same greatness as Allison and Katie to go 1:53 in your opinion. I won’t be surprised if you have none. And if it is so then booking my February opinion maybe a wise thing to do I would think about Ledecky and Titmus only. Ledecky – because I just want her to do so. And my opinion about her chances will form as soon as I see her two in-season 100. Titmus – because of her progress curve in wide… Read more »

AuggieBuschFan

I mean Pellegrini went 1:54.2 this past summer and if I remember correctly won the last 2 World Championships. If you wanna know what she’s up to its greatness. I just think its funny that you ignore this fact when shes been the fastest time since 2016 and it was just this past year. But to give your statement a response, 1:53 probably just looks less than .3 faster than what Pellegrini went last summer…….

AuggieBuschFan

Braden I really think we should lay off him. He’s an expert in capitalizing words therefore, he proves he has the credentials to make his claims about….. swimming…..

UpstateCoach

!RemindMe 6 Months from now to check up on this….

Jim C

The men’s prediction for the 400 free already seems unlikely….

Superfan

Adding the 150o might be a factor and big of lineup she can handle. The mile is “surer” gold than 200 by a lot.

Swedishswimfan

Sarah wont swim.

Pvdh

I think it’s Murph in the 100

Sir Swimsalot

He kinda rotates on and off years. One good, one bad, and so on. I believe he’ll be firing on all cylinders this year

Sean S

If he’s not on a trials he could lose out to Grevers and Casas.

Drama King

Whole Murphy , Plummer & Grevers situation will happen again. Hope Grevers will survive this time.

Steve

Manaudou 0.6% is pretty low too

Jeff

I think it’s mainly on the basis that the only international championships since Rio he has done is last years European SC champs so there isn’t much data to go on.

Steve Nolan

Agreed, though I’d prolly bump everyone ahead of him down a point or two and put him b/w 5-10%, if I’m just talking about what numbers I *feel*.

Dbswims

I like the idea of this. However, some of these are a little shakey. For example, i dont think sjostrom’s chances of winning gold in the 1 fly are that low. I also find it interesting how some events have more than 2 americans (like 4 women in the 2 breast, 4 women in the 1 back, 3 women in the 1500, 3 women in the 1 breast, 3 women in the 2 fly, 4 men in the 1 free, 3 men in the 1 back, and 3 men in the 1 fly). It shows how important the us trials is going to be.