Gurowake

Trivia bits

Recommended Posts

There are very roughly 150 torikumi per day.  The probability of getting 9 in a row on the same side, not caring which side, is one in 2^8, which is only 256.  Getting 9 in a row at some point during the day should happen roughly every other day.

  • Like 1

Share this post


Link to post
Share on other sites
1 hour ago, Gurowake said:

There are very roughly 150 torikumi per day.  The probability of getting 9 in a row on the same side, not caring which side, is one in 2^8, which is only 256.  Getting 9 in a row at some point during the day should happen roughly every other day.

That's not exactly correct since each "try" (i.e. streak of one side winning, or RNG flips for 1/256) take up a different number of bouts (up to 9). By my calculation (by that I mean my python script) it's about 24.7% for 150 bouts.

 

from collections import defaultdict

p = defaultdict(int)
p[9] = 1/256
for m in range(10,151):
  chance = 1/256
  for n in range(1,9):
    chance += 0.5**(n) * p[m-n]
  p[m] = chance

 

Edited by Kamitsuumi
mistake in script
  • Like 3

Share this post


Link to post
Share on other sites
6 minutes ago, Kamitsuumi said:

That's not exactly correct since each "try" (i.e. streak of one side winning, or RNG flips for 1/256) take up a different number of bouts (up to 9). By my calculation (by that I mean my python script) it's about 26.3% for 150 bouts.

I didn't think it would be correct, but it's more or less the right order of magnitude

  • Haha 1

Share this post


Link to post
Share on other sites
5 hours ago, Kamitsuumi said:

That's not exactly correct since each "try" (i.e. streak of one side winning, or RNG flips for 1/256) take up a different number of bouts (up to 9). By my calculation (by that I mean my python script) it's about 24.7% for 150 bouts.

I'm no one to validate your code, especially as my Python knowledge is null, but everything's invented now that they have internet in computers and damn it, I'll take advantage of it being as lazy as I am.

This web allows you to calculate the number of (exactly/at least/at most) heads in a row in X tries.

image.png.8421846f8720deb7197f69f5ad5b777e.png

So it should be around 26.29% for 150 bouts if we don't mind from which side the winning strike comes from, which is quite close to your result but I'm a picky arsehole.

Right now I'm way too sleepy to check everything and maybe I'm wrong and your code is right but if it helps somebody in some way, so be it.

 

5 hours ago, Gurowake said:

I didn't think it would be correct, but it's more or less the right order of magnitude

This one made me chuckle.

 

EDIT: I just noticed your previous calculation was 26.3% as it appears like that in Gurowake's quote. Why wasn't it correct though?

Edited by Oskanohana
Clarifications

Share this post


Link to post
Share on other sites
53 minutes ago, Oskanohana said:

I'm no one to validate your code, especially as my Python knowledge is null, but everything's invented now that they have internet in computers and damn it, I'll take advantage of it being as lazy as I am.

This web allows you to calculate the number of (exactly/at least/at most) heads in a row in X tries.

image.png.8421846f8720deb7197f69f5ad5b777e.png

So it should be around 26.29% for 150 bouts if we don't mind from which side the winning strike comes from, which is quite close to your result but I'm a picky arsehole.

Right now I'm way too sleepy to check everything and maybe I'm wrong and your code is right but if it helps somebody in some way, so be it.

 

This one made me chuckle.

 

EDIT: I just noticed your previous calculation was 26.3% as it appears like that in Gurowake's quote. Why wasn't it correct though?


The issue with the above is that you can't just multiple by 2 to get the answer:

By inclusion-exclusion:
{Probability of 9 consecutive heads or tails in 150} = {Probability of 9 consecutive heads in 150} + {Probability of 9 consecutive tails in 150} - {Probability of 9 consecutive heads and 9 consecutive tails in 150}

Since the third term on the right hand size is non-zero, {Probability of 9 consecutive heads or tails in 150} < 2*{Probability of 9 consecutive heads in 150}

Originally, in the nested for loop I had "range(1,10)" instead of "range(1,9)" (range is inclusive on the first parameter and exclusive on the second). This meant that I had an extra 1/512*P_{m-n} in each sum.

  • Like 1

Share this post


Link to post
Share on other sites
22 minutes ago, Kamitsuumi said:

The issue with the above is that you can't just multiple by 2 to get the answer:
 

Thanks for putting me in my place(Bow...)

I'm so fucking long gone from my marginal statistics studies...oh, boy.

Share this post


Link to post
Share on other sites

Oki was only the second Ms13 in the 6 basho era to fight in Juryo. The other was Shiraneyama in 1977.05.

In the 6 basho era, only 5 rikishi ranked lower on the banzuke, were allowed to fight in Juryo. Ms14 Wakahikari (1968.11), Ms14 Kotogaume (1983.11), Ms15 Kotonosato (1977.11), Ms16 Yoshinotani (1975.11) and Ms19 Naniwaryu (1975.03).

But opposed to Oki, they weren't there as fillers. All were 6-0 and fought for the yusho and only Kotogaume didn't manage to go 7-0.

Speaking of double digit Ms fighting Juryo (only 17 since 6 basho), the most notable should be Ms10 Gagamaru (2009.09 Y) and Ms10 Chiyonofuji (1974.09 Y), making Chiyonofuji the only double digit Ms to fight Juryo, take the yusho and eventually become Yokozuna. 

  • Thanks 2

Share this post


Link to post
Share on other sites

Since his rise to yokozuna, Terunofuji was 6-0 against ozeki.

Until yesterday happened...and then today. He choked big time. He's really cursed in Nagoya.

Sumodb query

Share this post


Link to post
Share on other sites
4 minutes ago, Oskanohana said:

He's really cursed in Nagoya.

Funny you should mention it, but on that note, his one July basho win wasn't in Nagoya.

Edited by Seiyashi

Share this post


Link to post
Share on other sites
7 minutes ago, Seiyashi said:

Funny you should mention it, but on that note, his one July basho win wasn't in Nagoya.

I was too lazy to look for the thread where it was mentioned, somebody analyzing the "Yusho Grand Slams" and the correction that he won a yusho in July but the year it wasn't in Nagoya because covid.

Share this post


Link to post
Share on other sites
3 minutes ago, Oskanohana said:

I was too lazy to look for the thread where it was mentioned, somebody analyzing the "Yusho Grand Slams" and the correction that he won a yusho in July but the year it wasn't in Nagoya because covid.

Guess who pointed it out. B-)

Share this post


Link to post
Share on other sites
3 minutes ago, Seiyashi said:

Guess who pointed it out. B-)

Had you said "you" referring to me, it would have been incorrect. Your correct answer would be "me" referring to you.

image.png.604cba5a8ed2d96e3769a19f4dcc8c1b.png

  • Like 1
  • Haha 4

Share this post


Link to post
Share on other sites

Only the second time in the 6bpy era that three consecutive Makuuchi yusho were achieved with 12 or less wins. The first one was in the period of 1972.01-05 with 11, 12 and 12 wins, respectively.

Fascinatingly, the 1972.01 tournament was won by M5 Tochiazuma I. without a playoff (6 guys ended up at 10-5, two of whom lost in regulation on the final day). Note that Makuuchi consisted of 36 members in those day, in contrast to today's 42. FWIW.

 

This is another indicator of transition times. 1972.05 saw Wajima's first yusho (from Sekiwake rank), while it was also Kitanoumi's Makuuchi debut basho (9-6).

Edited by yorikiried by fate
One more thought.

Share this post


Link to post
Share on other sites
12 minutes ago, yorikiried by fate said:

Fascinatingly, the 1972.01 tournament was won by M5 Tochiazuma I. without a playoff (6 guys ended up at 10-5, two of whom lost in regulation on the final day). Note that Makuuchi consited of 36 members in those day, in contrast to today's 42. FWIW.

Regarding that basho, what the hell is THIS?

Why did they get the fabulous idea of pairing a yokozuna and an ozeki on shonichi and immediately discarded it afterwards? I would be all for it, really. Is there any explanation?

Edited by Oskanohana
Questions
  • Confused 1

Share this post


Link to post
Share on other sites
8 minutes ago, Oskanohana said:

Regarding that basho, what the hell is THIS?

Why did they get the fabulous idea of pairing a yokozuna and an ozeki on shonichi and immediately discarded it afterwards? I would be all for it, really. Is there any explanation?

Royal visit, maybe?

Share this post


Link to post
Share on other sites
2 hours ago, Oskanohana said:

Regarding that basho, what the hell is THIS?

Why did they get the fabulous idea of pairing a yokozuna and an ozeki on shonichi and immediately discarded it afterwards? I would be all for it, really. Is there any explanation?

I wonder if it was simply to freshen things up a bit as Kitanofuji was a lone yokozuna who had won the previous two tournaments and was a heavy favorite for the yusho again. 

Share this post


Link to post
Share on other sites

Nishikifuji got 3 wins by fusen on the same basho for the first time in history in makuuchi. As a master of the technique, he should've been awarded the gino-sho.

Query

He equalled ma boy Kasuganishiki, but "The shopkeeper" only made it in juryo. Weak. I wonder if the feat did cost him some kesho-mawashi back then.

Edited by Jakusotsu
streamlined the query
  • Haha 3

Share this post


Link to post
Share on other sites

Rikishi (15-bout era) who started their sekitori career with at least 9 wins in each of their first two tournaments and never reached makuuchi:

Rikishi Debut Debut Rk Records After Rk High Rk J Basho
Wakatsubaki 1952.09 J17w 10-5 ➝ 9-6 J8e J2w 9
Chikugoyama 1954.03 J21e 13-2 D ➝ 10-5 J4e J2e 14
Sakunobori 1957.09 J22w 9-6 ➝ 9-6 J14w J6w 27
Nishinaka 1958.07 J23e 9-6 ➝ 9-6 J13e J7w 9
Tamanoura 1958.09 J22w 10-5 ➝ 10-5 J7e J7e 10
Suiryu 1977.07 J13w 9-6 ➝ 9-6 J3w J2e 22
Hakuryu 1979.05 J13w 9-6 ➝ 9-6 J4e J1w 47
Dairaido 2005.09 J14e 9-6 ➝ 10-5 J2e J2e 6
Kotokuni 2009.01 J14w 9-6 ➝ 9-6 J4w J4w 4
Asanowaka 2021.11 J13e 10-5 ➝ 9-6 J4e (J4e) (5)


Full list of 9 ➝ 9 starters in juryo, plus those who made makuuchi after one basho.

Edited by Asashosakari
  • Like 3

Share this post


Link to post
Share on other sites

Asanowaka will eventually leave this list. I am less confident about Dairaido though.

  • Haha 1

Share this post


Link to post
Share on other sites

I don't know if there is any way to prove this by scraping the DB, but i'm sure, Kawazoe is the first and only rikishi to face an ex-Ozeki in his debut bout. And again i'm pretty sure, that this is a "record" for eternity.

Share this post


Link to post
Share on other sites
37 minutes ago, Benihana said:

I don't know if there is any way to prove this by scraping the DB, but i'm sure, Kawazoe is the first and only rikishi to face an ex-Ozeki in his debut bout. And again i'm pretty sure, that this is a "record" for eternity.

If I'm not mistaken, Terunofuji has been the only other former Ozeki competing below Juryo, and it's easy to check that he didn't meet any tsukedashi there.

Edited by Jakusotsu

Share this post


Link to post
Share on other sites

First, thanks to Gurowake and others on the basho discussion thread for mentioning this tidbit... the extreme rarity of lower rank 1-0 vs 0-1 rikishi getting matched on the torikumi.  Now I finally got some time to try the db query and confirm.  I'm very unskilled when it comes to the query, so welcome others to amend this trivia bit.

   The only two other 1-0 vs 0-1 makushita matchups were:
Nagoya 1988 Day 4: Ms33e Shinshi (1-0) vs Ms31w Tochimusashi (0-1) and
Kyushu 1974 Day 3: Ms11w Yokoyama (1-0) vs Ms13e Shironishiki (0-1)  
   During this basho, the  Ms2w Yago (1-0) vs Ms2e Tomokaze (0-1) match on day four was the first time ever that the 0-1 rikishi won.  makushita 1-1 after the bout.

  I did a check of the other divisions' matches and 0-1 winners:
Sandanme:   3 matchups with 2 of the 0-1ers winning.
Jonidan:        4 matchups with NONE of the 0-1ers winning.
Jonokuchi:   74 matchups with 25 of the 0-1ers winning including twice in the 1997 Nagoya basho!
 

Other than Jonokuchi, very rare.

Share this post


Link to post
Share on other sites

In doing the above queries, I also found this rarity:
2-0 vs 0-2 in the lower ranks.  1998 Hatsu: Jk46e Kiyohara (2-0) vs Jk46w Fukushimoa (0-2)

and the occasional....

 

Share this post


Link to post
Share on other sites
4 hours ago, shimodahito said:

In doing the above queries, I also found this rarity:
2-0 vs 0-2 in the lower ranks.  1998 Hatsu: Jk46e Kiyohara (2-0) vs Jk46w Fukushimoa (0-2)

and the occasional....

 

I wish I had been there to see the legendary bout that settled the Triangle Bragging Rights.(Firstprize...)

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now