Totally useless information

[Bealzbob]

Did you know that not a single rikishi in the current makuuchi banzuke was born in the month of December.

You probably didn't know, and probably didn't want to know :)

Teenagers in the makuuchi & juryo ? Just the 1 : 18 year old Wakanoho @ Juryo 13 East. Youngest makuuchi rikishi is Tochiozan @ 20 yrs old. He is 8 months younger than Kisenosato who is also 20.

Oldest rikishi in makuuchi & juryo ? Otsukasa @ 36 yrs old followed by Kitazakura, Tamakasuga & Tosanoumi (all 35).

The 4 tallest rikishi in makuuchi & juryo are all European. Kotooshu (203cm), Baruto (197cm), Roho (195cm) & Wakanoho (195cm). Next come 2 Mongolians in Hakuho & Kyokutenho (192 & 191cm respectively). The tallest Japanese rikishi is Bushuyama (191cm) @ juryo 12 west. New sanyaku rikishi Toyonoshima is the shortest rikishi in all of makuuchi & juryo @ 168cm (5 foot 6 inches).

The 3 heaviest rikishi are all Japanese. Miyabiyama @ 182kg, Iwakiyama @ 178kg & Kaio @ 175kg. Baruto is next @ 174kg. Only 2 rikishi are less than 120kg - Hakuba (J8e) @ 119kg and the lightest is Satoyama (M12W) @ 117kg.

Anyone else any useless info, feel free. I'm done for now (Shaking head...)

[Sokkenaiyama]

Nicely done. How'd you manage to photoshop MK and SF2 in the same image?

[philafuji]

I didn't find the information useless at all.

As a matter of fact, it was very useful for me. For instance,

I here the comentator's mentioning the height of Toyonoshima in terms of small, but I don't recall them saying what is exact height is.

Maybe you could post more of these every so often.

Thanks

Philafuji

[Bealzbob]

Nicely done. How'd you manage to photoshop MK and SF2 in the same image?

I didn't. I googled E.Honda and noticed someone had done him with Raiden so as both have Sumo links it seemed the perfect avatar :)

[kaiguma]

The 3 heaviest rikishi are all Japanese. Miyabiyama @ 182kg, Iwakiyama @ 178kg & Kaio @ 175kg. Baruto is next @ 174kg. Only 2 rikishi are less than 120kg - Hakuba (J8e) @ 119kg and the lightest is Satoyama (M12W) @ 117kg.

Anyone else any useless info, feel free. I'm done for now (Shaking head...)

This stuff is not useless at all, very interesting post. Or maybe I'm just obsessed with useless knowledge?

Whenever you post a stat list like this though, it's bound to be nitpicked - sorry it has to be me. For the "3 heaviest rikishi" portion, I'm almost sure you mean "3 heaviest sekitori"? I know it could be inferred from the context that you were talking about sekitori for all of the previous figures, but it's confusing not to mention it there. Same goes for "Only 2 rikishi are less than 120kg."

Heaviest of all rikishi is Orora, right? Next heaviest, if I recall, are Japanese Mankajo and Kainowaka. All three are in Sandanme with very little hope of stabilizing in Makushita. In fact, they may be the only rikishi over 200 kg.

The December birthdays thingy is very strange indeed. It loojs like only Kitazakura and Kyokunankai have December birthdays in all of Juryo. So only Kitazakura could break the cycle after this basho, now ranked at J2E. If Kyokunankia is demoted, Kitazakura will be the only Decmeberbaby of all Sekitori! What are the odds?

[kaiguma]

Heaviest of all rikishi is Orora, right? Next heaviest, if I recall, are Japanese Mankajo and Kainowaka. All three are in Sandanme with very little hope of stabilizing in Makushita. In fact, they may be the only rikishi over 200 kg.

Isn't Yamatoyama over 200?

Right you are. About 25 kilo under Orora and 10 over Mankajo. I think they are the only 4 then.

[Bealzbob]

Sorry, I should have mentioned that in all the stats I posted, they were all only for makuuchi & juryo. I didn't go into the depths of makushita/jonidan etc as I don't have a banzuke with hyperlinks to sumo.goo to add them to my spreadsheet :) But I would if I could !! hint hint ;)

[Hashira]

The December birthdays thingy is very strange indeed. It loojs like only Kitazakura and Kyokunankai have December birthdays in all of Juryo. So only Kitazakura could break the cycle after this basho, now ranked at J2E. If Kyokunankia is demoted, Kitazakura will be the only Decmeberbaby of all Sekitori! What are the odds?

For the odds of having no December babies in a 42-man makuuchi field, I get 2.4%. How's that for totally useless?

[Doitsuyama]

The December birthdays thingy is very strange indeed. It loojs like only Kitazakura and Kyokunankai have December birthdays in all of Juryo. So only Kitazakura could break the cycle after this basho, now ranked at J2E. If Kyokunankia is demoted, Kitazakura will be the only Decmeberbaby of all Sekitori! What are the odds?

For the odds of having no December babies in a 42-man makuuchi field, I get 2.4%. How's that for totally useless?

Ok, I feel compelled to chime in a bit. Firstly I get a probability of 2.6%. But the useless part of all this talk is that December is meaningless - ANY month without a birthday would have gotten Kaiguma's attention. While I'm too lazy now to calculate the probability of that, my guess is that it's over 50% probability that at least a month has no birthday in a field of 42 people.

[Sokkenaiyama]

I got 2.404% myself, using the 365 days per year model. Taking leap years into account, I got 2.411%. So please explain your methods, because you made me rather curious.

Edit: I was bored so I thought I'd calculate that probability you were too lazy to at the time. I got 31.238%. Not quite 50%.

Second edit: for some strange reason, I counted 14 months in a year. I updated the correct result.

Edited May 2, 2007 by Sokkenaiyama

[eciq]

The December birthdays thingy is very strange indeed. It loojs like only Kitazakura and Kyokunankai have December birthdays in all of Juryo. So only Kitazakura could break the cycle after this basho, now ranked at J2E. If Kyokunankia is demoted, Kitazakura will be the only Decmeberbaby of all Sekitori! What are the odds?

For the odds of having no December babies in a 42-man makuuchi field, I get 2.4%. How's that for totally useless?

Ok, I feel compelled to chime in a bit. Firstly I get a probability of 2.6%. But the useless part of all this talk is that December is meaningless - ANY month without a birthday would have gotten Kaiguma's attention. While I'm too lazy now to calculate the probability of that, my guess is that it's over 50% probability that at least a month has no birthday in a field of 42 people.

me lazy too...but if december probality is 2.6% that should be the same for all other months so that would make 12x2.6=31.2% probality (not 50) that at least a month has no birthd......

anyway fun with useless info (Laughing...)

cium cium eciq

[Sasanishiki]

In my experience there are a great many more people I know with birthdays in April than in any other month. I'd say weather, and the fact many people get married in summer are reasons women become pregnant around September.

My gf read something out to me just last night that the most prolific month for births is August - not sure if that is in a particular country (like NZ or US) or worldwide.

[Fay]

(Geburten - births, Sterbef

[Bealzbob]

I find it interesting and healthy for sumo that the top half of the makuuchi banzuke (top 21 wrestlers) are on average more than 3 years younger than the bottom 21 wrestlers in makuuchi (26.28 v 29.6).

Having said that, taking the top 2 divisions as a 70 rikishi league, the top 35 and bottom 35 are almost identical and the makuuchi banzuke and juryo banzuke are almost identical in average age too (just under 28).

[Stephanoshima]

I got 2.404% myself, using the 365 days per year model. Taking leap years into account, I got 2.411%. So please explain your methods, because you made me rather curious.

Edit: I was bored so I thought I'd calculate that probability you were too lazy to at the time. I got 36.691%. Not quite 50%, but close.

2.411% is correct, (1-31/365.25)^42=0.02411 :-P

But I wonder how you calculated the 36.691%. :-D

[Hashira]

hey, sorry for the late reply

i used 365.25 days in a year, and people born on 334.25 days not in December, then exponentisized that to 42 rikishi

sorry, don't know/remember the real math terms to use

[Sokkenaiyama]

I got 2.404% myself, using the 365 days per year model. Taking leap years into account, I got 2.411%. So please explain your methods, because you made me rather curious.

Edit: I was bored so I thought I'd calculate that probability you were too lazy to at the time. I got 36.691%. Not quite 50%, but close.

2.411% is correct, (1-31/365.25)^42=0.02411 :-P

But I wonder how you calculated the 36.691%. :-D

In a similar way. The probability that there is some month with no birth in a given group of 42 people is the given by the classic probability definition: no. of favorable cases / total no. of cases. The total number of cases is, of course, 365 to the 42. The number of favorable cases is the sum of the numbers for individual months, i.e. 7 times the number for a 31 day month, 4 times the one for 30 a day month and one for february, numbers that are given in the post above. The final formula:

7*(334/365)^42 + 4*(335/365)^42 + (337/365)^42

Of course, this model isn't taking leap years into account. The result will vary slightly taking that into consideration.

As an aside, I'm still waiting for Doitsuyama's method that yielded 2.6% for the 31 day months.

P.S. Are any of you guys watching snooker? Shaun Murphy pulled of an incredible comeback against Matthew Stevens earlier today. He came back from 11-5 down to win 13-12. WOW!

Edit: OOPS. I seem to know my math well, but I don't know how many 30-day months there are in a year.

Edited May 2, 2007 by Sokkenaiyama

[Fay]

P.S. Are any of you guys watching snooker? Shaun Murphy pulled of an incredible comeback against Matthew Stevens earlier today. He came back from 11-5 down to win 13-12. WOW!

Hmmmm,just told us in Eurosport that they want to show us the highlights of the match later, now that I know the result my eagerness is gone ... :-P Now I'm waiting for Ronnie to do the same :-D

[Sokkenaiyama]

Sorry.

[Fay]

Sorry.

no problem, I'm going to dry my tears, cause Ronnie lost in the moment ..... :-D

Edited May 2, 2007 by Fay

[Stephanoshima]

But I wonder how you calculated the 36.691%. :-D

In a similar way. The probability that there is some month with no birth in a given group of 42 people is the given by the classic probability definition: no. of favorable cases / total no. of cases. The total number of cases is, of course, 365 to the 42. The number of favorable cases is the sum of the numbers for individual months, i.e. 7 times the number for a 31 day month, 4 times the one for 30 a day month and one for february, numbers that are given in the post above. The final formula:

7*(334/365)^42 + 4*(335/365)^42 + (337/365)^42

Of course, this model isn't taking leap years into account. The result will vary slightly taking that into consideration.

As an aside, I'm still waiting for Doitsuyama's method that yielded 2.6% for the 31 day months.

P.S. Are any of you guys watching snooker? Shaun Murphy pulled of an incredible comeback against Matthew Stevens earlier today. He came back from 11-5 down to win 13-12. WOW!

Edit: OOPS. I seem to know my math well, but I don't know how many 30-day months there are in a year.

I was thinking along the lines of:

p(at least one zero-birthday month)=1-p(no ZBM)

p(no ZBM)=p(no ZB January)*p(no ZB February)*...*p(no ZB December)

p(no ZBM)=p(no ZB 31-day month)^7*p(no ZB 30-day month)^4*p(no ZB 28.25-day month)^1

p(no ZBM)=(1-0.02411)^7*(1-0.02733)^4*(1-0.03401)

p(no ZBM)=0.72884

p(at least one zero-birthday month)=1-p(no ZBM)=1-0.72884=0.27116

The strange thing is that I've run a little simulation for this, and its result is ~28.4% over enough runs to be sure that it's not just some random deviation from 27,1%, but a significant discrepancy. :-P.

After some thinking, I have come to the conclusion that the simulation is correct because the formula is based on all those probabilities being perfectly independent of each other, which they aren't.

Let's assume for a moment that there are only 11 rikishi. According to the formula, the probability of at least one ZBM is 99.7% (just believe me). However, since there are 11 birthdays and 12 months, it is intuitively clear that there always has to be at least one ZBM, hence the probability is exactly 100%.

Edited May 2, 2007 by Stephanoshima

[Sokkenaiyama]

Well, I used the definition so it can't go wrong. Anyway, like Bob the Lord of Flies said, all this stuff is useless (even if it's fun for those who like math). Maybe others might join in to set the record straight.

[kaiguma]

Very useless information everyone has been generating on my account . . . Good work blokes!

The irony is, my exact quote "what are the odds?" was in reference to:

only one Decemberbaby in all of sekitori rikishi.

That's 1 in 68, not 0/42. Of course my query was completely rhetorical - I didn't dream anyone would actually start crunching numbers. What was I thinking? Where am I? OF COURSE YOU WOULD!! I love it here . . .

Carry on. (Wearing a paperbag...)

EDIT: has someone scripted the SF platform to automatically correct "c-h-a-p-s" to "blokes?" Does this only happen to me? Do I have something to worry about, similar to Fujisan's earlier computer problems?

Edited May 4, 2007 by kaiguma

[kaiguma]

blokes

Haha. I get the same. Wow that's odd.

Someone's got to come up with a good conspiracy theory for this one! What is going on with IP.Board?

Test: chapstick

EDIT: useless it may be but I din't mean to take this (Wearing a paperbag...)

If anyone has a theory for the "blokes" phenom., I'm putting a post in feedback forum. We should discuss there.

Edited May 4, 2007 by kaiguma

[Stephanoshima]

Very useless information everyone has been generating on my account . . . Good work blokes!

The irony is, my exact quote "what are the odds?" was in reference to:

only one Decemberbaby in all of sekitori rikishi.

That's 1 in 68, not 0/42.

Ummm, right. Then the result should be:

68*(31/365.25)*(1-31/365.25)^67=1.515% (Laughing...)