Mathematical Way to Choose a Toilet - Numberphile

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Toilets at musical festivals are notorious - but how many should you check before committing!?
EXTENDED MATH ENDING: • Choosing Toilets (math...
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Animation: Pete McPartlan
Featuring Dr Ria Symonds from the University of Nottingham.
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25 июн 2014

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Комментарии : 919

@FlorianHassanen 10 лет назад

if you happen to attend a maths festival instead, you just pick the first toilet no matter what, since it will be in pristine condition, because every other attendee will skip it due to this video

@neplatnyudaj110 5 лет назад

The mathematicians will shuffle the toilets before they pick for exactly this.

@katphisH11 5 лет назад

The mathematicians will all follow this logic, which will defeat this assumption and change the Nash equilibrium

@leobozkir5425 4 года назад

😂

@alex_zetsu 4 года назад

A lot of these very interesting math problems (and riddles) have solid math, sometimes in complex pretty ways. But the framing devices are usually pretty bad. For example, in a maths festival, the first toilet is pristine. In a different festival, the toilets will be degrading in quality over time, while the premise and the 37% rule assumes that the quality will be unchanged.

@seankauder9721 4 года назад

The order of selection isn't the same for everyone. Your first toilet and other's first toilets may be different

@SebTsch 8 лет назад

Instructions unclear, I pissed myself.

@SebTsch 8 лет назад

Liam Swearengin Are you alright? :)

@puct9 8 лет назад

Instructions unclear, found myself in a large hadron collider.

@RapManJak 7 лет назад

SpudShroom Spud it's still better than the worst toilet in Scottland.

@JakeCakeful 10 лет назад

I always have a more psychological approach to picking a toilet, rather than the mathematic. Always pick one of the toilets facing out towards the road, people are much more unlikely to use those toilets. So even though it's a little shameful to walk out to people staring, those toilets are almost perfectly clean because people want to use those facing away from staring people. Just some good advice. Pretty much choose the toilet that seems the most awkward from the outside, since it will be the nicest from the inside.

@thatoneguy9582 6 лет назад

Jacob Kofoed Until lots of other people try that

@Thebiggestgordon 4 года назад

That One Guy yeah he shouldn’t have commented it, know we know and will this

@jasondeng7677 4 года назад

'nobody cares about me' so let's use that to my advantage!!! no but really, to you, i am 2 sentances, we most likely will never see each other ever again, and to you, on the surface, i am not a human like the people around you, simply an image of a chicken followed by text.

@elishahar6669 8 лет назад

years of learning mathematics put to the ultimate test HOW TO CHOOSE A TOILET

@dexterovski 8 лет назад

I mean, who can say that math is useless after this?

@crabstickz 10 лет назад

What are the chances of me pissing my pants by time I've done the maths?...oh wait. Never mind.

@Zekomaru 6 лет назад

crabstickz 37%

@kblewis3331 11 месяцев назад

100%, because who/s got time to wait out the queue to 37 toilets

@robertyang4365 9 лет назад

0:33 Professor J Grime James Grime LOL

@vircaprae3060 7 лет назад

@fuseteam 7 лет назад

LOL

@nihilist1680 8 лет назад

What if I told you that not a single toilet in festival area is clean

@rockwitharms7455 8 лет назад

Paska juttu

@Galdring 8 лет назад

What? You really saying the legendary chandeliered ladies' room is a mere myth?

@spork4464 8 лет назад

+HarbourOfMarbles XD

@lazaruslong697 8 лет назад

+HarbourOfMarbles I have seen something hanging from the ceiling on those toilets, but i am pretty sure that weren't brown chandeliers. :D

@astrogod_ 7 лет назад

+Nihilist So observe the first 37% of the first toilets you encounter. Afterwards, make a comparison between the next toilets to the previous 37% of observed toilets. As you continue looking and no toilets are cleaner than the previous toilets you've observed and if you reach the last toilet and realize that all the toilets are dirty, unfortunately, you would have to choose the last toilet. Because remember, there are a line of people behind you who are also waiting to use a toilet. You can't go back to the least dirtiest toilet. *RIP* ;>

@ChessNetwork 10 лет назад

Q: How to determine which video to watch from your subscriptions? A: 'Choose' the one with 'toilet' in the title.

@pjoden 6 лет назад

Nice to see you here, Jerry!

@AR-jt2ux 6 лет назад

Wtf. How did I run into you here?

@matanrubin8726 6 лет назад

Fancy seeing you here, Jerry

@anujmalhotra8543 5 лет назад

I wasn’t expecting to see you here !

@AyrtonTwigg 5 лет назад

I thought I was on the wrong channel when I saw you.

@minmax5 9 лет назад

This is assuming there are any clean toilets of course lol

@Mister_NO. 8 лет назад

+Comrade Max There is a whole lot of "assuming" in this video to be honest (and extremely polite)... These kind of a Statistics only work in theory.. Imagine a city where there are only 3 people. One has 3 cars, others have nothing.. Statistically speaking, each man has a car... That's "statistics" for you...

@PaulMagnusSrensenClark 8 лет назад

+Comrade Max They are only talking about relative best of the available sample. Even if all are bad there will still some that are better than the others.

@minmax5 8 лет назад

Paul Magnus Sørensen-Clark I know, i was just joking.

@numberphile 10 лет назад

A twist on the secretary problem for Glastonbury... Help support our animations by buying brown papers or artwork from this video: bit.ly/brownpapers Next week: We meet math legend Ron Graham

@GirGir183 8 лет назад

+Numberphile Is this also a twist on The Monty Hall problem? I'm not half way through the video yet.

@NoriMori1992 8 лет назад

+Selinor578 No, it isn't.

@NoriMori1992 8 лет назад

+Tom Delorme Then you get a shitty toilet. (Pun intended.) It's not a perfect system, it just has the best chance of working.

@MegaMGstudios 8 лет назад

#PortyProblem

@hamfan1355 6 лет назад

Also known as the wedding problem. Know for it’s elegant solution in analysis.

@Fifth_Ace 8 лет назад

the problem is, that in real life all the toilets look like 3. Hence that is the best option, hence your real chance of picking the best one is 100%.

@PawlOwl 10 лет назад

lol, i have to date 37% of all women in the world before i can settle down?

@numberphile 10 лет назад

no, more than that.. you have date 37% of them and then keep dating more until you date one who is better than everyone that came before.... that might take a while.... More realistically, say you plan to date a certain number of people in your life... this is saying that after the 37% point, you should stay with the first person who is best so far --- that gives you the best chance of having settled with "the right one" from your smaller sample! :) Good luck

@PawlOwl 10 лет назад

Thats great advice. I'll get right on it!

@DPortain 10 лет назад

***** The biggest constraint is usually distance, followed by age. Most people don't want a relationship with a person living more than 50 kilometers away from them, which constrains the dating pool by a factor of 1000 to 50000.

@atomicmrpelly 9 лет назад

PawlOwl I love the combination of using probabilities and statistics to determine how to find an ideal partner, with the phrase "the person you are supposed to be with for the rest of your life", as if somebody who believes in soul mates is going to devise a mathematical solution to help them find theirs!

@ktrifon 8 лет назад

+Michael Nguyen hahaha! the smartest comment!

@lauren_e_s 8 лет назад

Reverse psychology: Now I know to go to the first toilets because everyone will go to the later ones. Reverse reverse psychology: People will probably choose the first toilets knowing that everyone else will choose the later toilets, so I should choose the later toilets.

@ricardoalves9605 8 лет назад

well but then everyone else would do the same as you

@lauren_e_s 8 лет назад

+Ricardo alves. Then use reverse reverse reverse psychology.

@friggingbomb88 8 лет назад

+Løgan Schlick i would just pee my pants and down a few shots to forget about the embarassment

@ObjectsInMotion 7 лет назад

Løgan Schlick That's not what reverse psychology means. You're just being intentionally idiotic.

@robintaylor3713 6 лет назад

do one pass by all of them before you badly need to go to assess a couple favourites. Then go back half an hour later when you do need to go.

@kodyonthekeys 10 лет назад

Anyone else see Prof. J Grime graffitied on bathroom 4's wall? Great attention to detail. haha

@TheGrooseIsLoose 8 лет назад

So if I take the world population of women in my age range, plus some random polling results about how many women are single, I find that I have to date 42 million women, then marry the first one that's better than the previous 42 million, or the last one. What an interesting breakup line: "It isn't you; it's the fact that you're only number 39,863,264. I haven't hit 37% yet!"

@7James77 5 лет назад

Technically I believe the 37% is of 100. The higher the number the lower the percentage.

@ashantraveler 5 лет назад

@@7James77 actually, it is not. It is 1/e %

@rahulkanchangaikwad 9 лет назад

bring your own toilet belore it's toolet

@candycorncrafts5207 8 лет назад

If the first one looks like 1 or 2, don't waste your time and take it!

@7James77 5 лет назад

I know, right? They are like "you gots to do 37% first" no, no I do not. If it gotta clean hole I'm a going in there

@AlanKey86 10 лет назад

Ooh... this video got a bit Meta. We get to *choose* which video we watch - continue with video 1 or switch to video 2??? It's like a maths problem in and of itself!

@pmcpartlan 10 лет назад

Should've made 100 videos.

@origamigek 8 лет назад

Reject the first, choose the second.

@SkyrimHod 10 лет назад

So I should date at least 1-2 billion people before settling down? ;)

@TommiHimberg 10 лет назад

No wonder the toilet queues at festivals are so long - it's a bunch of Numberphiles optimising their experience! :p

@Guywithcrazyideas 10 лет назад

Realism vs. math / theory do not match when dealing with this subject. Trust me.

@ARP2wefightforyou 8 лет назад

+R3Testa imaginary numbers are very real. If you learn quantum mechanics, you'll run into imaginary numbers.

@Joaking91 8 лет назад

+Levi Quickburger5000 “When will we want wantons” Dude you don't even have to go that deep... AC current analysis uses imaginary numbers.

@TechnoRaabe 4 года назад

Or everybody is a mathematician

@neilkauffman1075 3 года назад

@@ARP2wefightforyou Well, technically, imaginary numbers aren't actually "real", per se, but imaginary.

@guilemaigre14 10 лет назад

the funny part,,is that in less than one hour I will be on my way for the Graspop Metal Meeting festival, so thanks you, this is very accurate for the moment !!

@numberphile 10 лет назад

hope it is useful!

@llgla 8 лет назад

By the time I looked through 33 toilets, I would have peed myself (>.

@PaulMagnusSrensenClark 8 лет назад

+llgla If there is more toilets than you have the time to check you must set N to the maximum of toilets you are willing to check. F.ex. there are 100 toilets, so N=100. But you are only willing to check 20 toilets because you really have to pee, or you have friends waiting, etc. So you reduce N to N=20. 0.37*20=7.4, so you check and reject the first 7 toilets, then you select one among the remaining 13.

@chandir7752 8 лет назад

You don't have to check the first 37 toilets, but the first 37% of all toilets. That means that if there are only 8 toilets, you only have to chack the first three toilets (37% * 8 = 2.96 ≈ 3) and then take the next toilet that is better then all the toilets you've already checked

@jameshiggins-thomas9617 5 лет назад

Is there a variation of this when the number of "toilets" is unknown? Although I've (luckily) not needed to job search often, but when I have I noted that there is a challenge - from both sides of the desk: how to choose the "best" fit given that you have a limited time to say yeah/nay to each possible. For example, as the employer, when you find a possible fit, do you go ahead and extend an offer or keep looking for a better fit (risking the former moving on)? As a job seeker, do you accept an offer or keep looking for a better package (risking either a poorer later option or none at all)?

@kkme7 7 лет назад

Had to laugh out loud at 0:32! That Prof. J. Grime sure knows how to use a toilet!

@captainpsychedelic3910 8 лет назад

Hahaha 0:43 Dr. J Grime tagged on the wall in the nasty portable (the redhead mathman)

@SomeRandomFellow 9 лет назад

I just realised 0:35 ish says "Prof J Grime" on the nasty toilet

@donkeyk578 10 лет назад

OMG look at all the THINGS in Brady's house!

@Laittth 4 года назад

Or just choose the one with a freaking chandelier in it when you see it

@SONOFAZOMBIE2025 10 лет назад

What happens if you find a toilet that _isn't_ smeared with poo, and soaked in urine, and is perfectly acceptable on your first door? Should one theoretically keep looking?

@shichengrao5314 4 года назад

Son of a Zombie I guess no

@Intermetheus 10 лет назад

So great to have Ria back. She is one of my favourites. ^__^

@MikeSpinak 8 лет назад

That seems like a solution with toilets and secretaries, where you can determine the total number of candidates - but can this even be applied to choosing a partner? In regard to dating, you're supposed to date 37% of the set of candidates, then choose the next one that's better than any that came before? Besides the fact that there's a fair chance you'll go through all the candidates without finding any in the last 63% that are better than the best in the first 37%, it also doesn't seem to have a practical application if you don't know in advance the size of the set of candidates.

@insanimal2 2 года назад

Well there's 7.7 billion people on the planet, so... this might take a while

@andrewwong7617 2 года назад

Assume your peak sexual market value lasts about 5 years. After 5 years your own likelihood of scoring “better” decreases drastically. That will be the total time box. Next, begin dating and rejecting prospective partners until you get an average rate of how many dates you get per year. Let’s say it’s 1 date per month. The total sample size is 60 prospective partners, so you should reject the first 22.2 dates before choosing the next best.

@bvedant 2 года назад

Exactly what I was thinking

@TheBaseballfreak95 8 лет назад

I tried this on a stretch of road in New Jersey. On this particular stretch of road there are 13 gas stations. My goal was the find the cheapest gas per gallon. So like we learned in the video I passed by the first 36% of gas stations (about 4 gas stations). I took note that the cheapest gas was $1.65 per gallon. So the theory in the video says to take the next best one after that, so anything less than $1.65 per gallon. I passed 2 gas stations that were $1.65 or greater and then the next one was $1.55 per gallon. This actually ended up being the Chester gas along that stretch of road.

@PaulMagnusSrensenClark 8 лет назад

+Kevin Hayes Awesome! That's a brilliant real life example of this actually working!

@fearlesscrusader 7 лет назад

Kevin, most of the time I'm on a road trip I'll being going home via the same route, so I keep track of the cheapest gas and stop at that station on my way back.

@Madoc_EU 10 лет назад

Awesome idea to let the viewer choose between the short and the complete version.

@alemutasa6189 7 лет назад

I like factorial numbers... It's like they're announcing themselves in a nice and enthusiastic way. "I'm 6 :D, solve the equation that features me!"

@SquirrelASMR 2 года назад

The best toilet is always the one in the abandoned corridor of the school or on a different floor at your office job.

@James196007 8 лет назад

It strikes me that the best option is to pick the toilet that is the hardest to get to and use that. Unless all the toilets are constantly in use, that is the one that will receive the least use and therefore probably be the cleanest.

@GeoCaptTerror 10 лет назад

Love the Prof J. Grime easter egg :)

@stapler942 4 года назад

Combine the toilet problem with Hilbert's Hotel and Last Light, and you find yourself searching 37% of an infinite set of toilets to find a clean one, then trying to turn off the lights of every single one before an infinite bus of guests shows up to occupy even more toilets.

@achaaaab 8 лет назад

Such an interesting and non-trivial problem with many practical applications ! Also, Dr. Wiseman has a very pleasant voice to listen :)

@Evija3000 8 лет назад

I was hoping it would be closer to life, like take into account which ones people actually use most (maybe the ones on the ends of the line or sth), but nop.

@fullyverified7491 8 лет назад

yeah

@NoriMori1992 7 лет назад

Evija3000 It's just demonstrating an algorithm. It's not supposed to be realistic.

@Evija3000 7 лет назад

I guess. I was just more interested in the issue presented in the demonstration than the algorhythm itself =P

@piratemeow 9 лет назад

My friend brings hand sanitizer, toilet paper, wipes and air freshener and finds a secluded place in the grass and takes a dump.

@isavedtheuniverse 7 лет назад

I liked seeing all the non-Grey approved stuff in your house. I have been catching up on old HI episodes and old Numberphile episodes.

@kkira22 9 лет назад

I'm studying for the GRE right now and strangely enough this video is a very relevant and helpful review. Thanks!

@Oh-pl8xe 8 лет назад

My solution - using psychology 101. For the 4 toilets: between 1 and 4, 90% of people choose 3. So the 3rd toilet will be the most visited, therefore the dirtiest. -After a time, people will keep going to the 3rd one, and then realize it's dirty, so they will choose to go to the nearest one. The 2nd and the 4th. -Given that most people are right handed, they will prefer the 4th. So the toilets 1 and 2 are the cleanest ;)

@fishmamma4846 8 лет назад

According to The Mythbusters, the second toilet is always the dirtiest

@blazejecar 10 лет назад

So you're saying that before you choose your soulmate you have to date 37% of the prefered gender population? seems credible xD

@himeatashi8035 9 лет назад

blazejecar Or 37% of prefered gender population that A) You know. And B) You would have xxx with. (If you are Asexual ignore B.)

@mrhappy192 8 лет назад

+blazejecar To be more realistic, you'd probably want to put in more criteria. For example, you'd date 37% of all women that live in your city, that like the same genre of music, that watch Numberphile, that are single. Then you'd get a more possible dateable number of women :P

@Joaking91 8 лет назад

+blazejecar Nope, only 37% of those who would be interested in you.

@robintaylor3713 6 лет назад

I think its 37% of the number of dates you could go on in a lifetime. So going with my current statistics and rounding up I need to go on 1 date.

@bentonstacy6315 6 лет назад

blazejecar when your crush happens to be in the first 37%...

@Kmno444 10 лет назад

Two of my favourite things Brady! Maths and Toilets. Great video. Thanks for the extended ending! Kate

@Nyuffykah Год назад

🤣🤣🤎

@nowonmetube 5 лет назад

The sound effects are really a reason what makes those videos great 😂

@osobliwynick 10 лет назад

But what if there is no better toilet than all of 37% that I've checked? Why if the best toilet is in that 37%? I will check all 100% toilets and finally left with nothing.

@garyweibel1372 6 лет назад

That's what I was asking

@theodorberza9933 9 лет назад

Go to the most isolated one. Most people pick what's closer to them so very few would have gone to these.

@Acer010203 10 лет назад

I love this! Keep this up :)

@gabesonic 10 лет назад

With a title like that this should be a good enough video to watch while I'm eating lunch.

@supiskibaimawesome 10 лет назад

Love the James Grime graffiti.

@spottedstar1123 8 лет назад

or just go to the one thats the furthesr from the line

@sharpphilip 9 месяцев назад

I love this whole video, but especially the watercolor art is brilliant this time round. I wish the rocket-propelled toilets bit around 4:50 or so were available as a print 😅

@davidsweeney111 10 лет назад

Great video, really enjoyed it and learned something new as well, now on to the maths .....

@xDAZZE 7 лет назад

And what if there's no "best option" in the last 63%? That is, the best is within the first 37/100, and none after fair better than all the first 37%? Do you just take the last one?

@minerscale 4 года назад

yep! no matter how bad it is

@sdfksdjbfuvygvyisdvcgvucgyvgy 8 лет назад

This is just overthinking, I just choose the first available toilet, dirty or not. That's what sinks are for.

@elonmusk501 3 года назад

Imagine mastering all math and got a chance to make videos on toilet.

@BunniBuu 10 лет назад

This is very useful for a game that I used to play! They would offer you 10 items, one at a time. If you accepted an item, you got it. If you rejected it, you would be shown the next item and you couldn't go back. I would have totally liked to use this back then! I could have declined the first four items, then looked for the next best over the better of the 3rd and 4th items :O

@Asharon 3 года назад

it would be interesting to know, how often you select a toilet that is above average using this, not only the first one.

@eomoran Год назад

You have a 1/e chance of choosing the best toilet by using this method. Coincidentally number of toilets (100) over e is the amount of toilets you have to go through to before making this decision. I believe it’s related to the rate of change of e to any power being equal to e to that same power at any instant (that is d/dx e^x = e^x)

@ahorrell 10 лет назад

Yeah, I'm not going to view and reject 37 toilets before I start ACTUALLY choosing. I'm going to keep looking until I see one that meets a subjective standard.

@donmoore7785 4 года назад

The animations are absolutely awesome! This was a lot of fun in 7 minutes... gotta go. Get it?

@Becky_Cooling 4 дня назад

i went to a festival last week and i used this maths to choose a toilet, but by the end of the week all of them stank so badly and there were so many flies that they were all about equal.

@THEQueeferSutherland 7 лет назад

There's a way better solution actually, don't go to music festivals. Seems like a nightmare to me.

@groinBlaster31 5 лет назад

Wow bro the millennium prize foundation will mail you your price shortly

@BodywiseMustard 4 года назад

All the better then, music festivals aren't made for people like you!

@gamechanger5432 Год назад

Here After Astroworld concert.

@NoriMori1992 6 месяцев назад

This "solution" fails for people who like music festivals. Which is presumably most people you find at music festivals, because otherwise why would they be there.

@deadasfak 10 лет назад

Trying to get viral again, Brady? :D

@Bistromathematic 10 лет назад

Great animations!

@Qermaq 10 лет назад

Hey Dr. Symonds is back! Yay!

@alexyanci7974 10 лет назад

Maths and pretty women. Ain't nothing better.

@xXxBladeStormxXx 10 лет назад

First toilet says: Prof. J(ames) Grime!! HAHAHAHA XD Anybody else noticed?

@alfredomarquez1916 10 лет назад

It's nice that you gave an option for people who are in a hurry, considering the subject matter.

@GraveUypo 7 лет назад

@ 2:30 how do you not know it's the best? it's all pink and has a freaking chandelier in it!

@alexyang6484 8 лет назад

How did I get here

@VoldieFromTheHerd 10 лет назад

Did anyone else notice the "Prof. J Grime" on the inside of that one toilet? It's obviously not important to the problem, but I thought it was kind of funny. (:

@zsmb13 10 лет назад

I think this has a great chance of going viral, Brady.

@yuvraj7214 7 лет назад

3:56 4th toilet has the name prof. J. Grime

@NeverInterpreter 10 лет назад

After checking 37% of the toilets you might not need a toilet anymore... P.S. Dr. Ria Symonds is incredibly charming

@RitzyRay 8 лет назад

i am so confused on why this was in my recommended

@iden01 8 лет назад

same Is youtube trying to tell us something

@the_blind_chick 8 лет назад

+Unidentiviable Yes! All our mathematical knowledge & years of schooling are going down the toilet! LOL

@saboienterprises 8 лет назад

This is a really cool concept. It was also showcased in Things to do and Make in the fourth dimension.

@SantiagoArizti 4 года назад

I remembered this video now I am playing Animal Crossong: New Horizons, for the Turnip game. So I will listen to the first 37% of the week, and then take the first better offer I get from the rakoons. This turns out to be around Tuesday AFTERNOON (after checking all previous days, of course)

@enbycharlie6287 4 года назад

I came for the same thing. Thanks for giving the answer in your comment

@DanielBeecham 10 лет назад

What if I am allowed to go back (which is usually the case)?

@AskiFin 10 лет назад

that case check every toilet and you always get the best one.. or interview everyone and hire the best Whats the problem here? This mathematical problem requires no-backsies, if you can go back you'll always get the best

@DanielBeecham 10 лет назад

AskiFin; Yeah, you are right in that the problem needs to be better specified. Perhaps I want to optimize for time (trials).

@Omni315 10 лет назад

If you check the first x toilets out of y total toilets the probability of the best toilet being one you've checked is x/y

@rilesmcgiles3493 10 лет назад

Daniel Beecham There's a problem with that too, if you want to optimize for time then you just pick the first toilet you open. If you can go back to any toilet then you have to decide between time and accuracy. I guess you would have to judge it based on how bad you have to go to the toilet or how soon you need a secretary.

@nnoose 10 лет назад

check all and go to best...

@Duncanated 10 лет назад

Warning: don't be drinking while watching this video.

@sean999ification 10 лет назад

Good video. I like the option break.

@rootvalue 6 лет назад

Okay... the flying 4th toilet animation... this is why I love Numberphile. This specific reason.

@RedBar3D 10 лет назад

Has anyone else's youtube layout on the iPhone app changed?

@nuclearminecraft9338 10 лет назад

Yes.

@jkennedy299 10 лет назад

Yea it's shit

@QuantumFracture 10 лет назад

The power of Math, bitches!

@MaverickSteffen 5 лет назад

Great explanation!

@mieszkomazurek3033 2 месяца назад

Yesterday I ran a half marathon and before the start there were 20 toilets in a row. I reminded myself this rule so I looked directly at the 7th toilet, then I looked 4 more to find the one better than the one before. It was fairly clean, there was still some paper. It smelted bad but that's fine. I didn't have time to look at all of them. Thank you for this video.

@mapu1 10 лет назад

Or you can just go to bathroom before the festival. Or get a bottle or jar.

@jalle88 10 лет назад

Most festivals last for days. Good luck with that!

@giggitygoebbels3612 10 лет назад

Or wear diapers

@mapu1 10 лет назад

jalle88 Go to hotel/wherever you are staying, use bathroom, go back. Bam. That's why I said the part about jar/bottle.

@cbernier3 10 лет назад

***** People camp out at music festivals, the toilets there aren't any better. And if they are staying off site at a hotel, this still isn't practical. How much time would this waste? Think about it. The people don't want to miss any music, loss their spot up front near the stage, or even wait that long to go. Plus don't forget that people are often drinking and/or doing drugs at these things, which only complicates the matter. Their plans to get back to a hotel would be a long walk, or sharing a taxi. That isn't something they can do multiple times a day.

@Matt-pr1xv 10 лет назад

"You might come across the problem that there's always lots of toilets to choose from." - Taken out of context, this positively *screams* #firstworldproblems.

@TheD1ddler 10 лет назад

Great! Now I know how to cut a cake, and pick a toilet after I am done eating it! Life skills from Numberphile :P

@DragoniteSpam 10 лет назад

And this is why math is the best thing ever.

@hummanuhblubberrumma 10 лет назад

4:01 AM.

@hummanuhblubberrumma 10 лет назад

liek srsly?

@lindybeige 2 года назад

But if the single very best loo is one of the first 37% you looked at, then you will have to look at all of the rest, and you will never find a better one.

@s4623 10 лет назад

A tiny problem with this algorithm is that the number of UNOCCUPIED toilets has to be known in advance..... With some large number of toilets, how do you determine that number of unoccupied toilets? (It's not like you can count before you can start opening doors because they don't have huge flags for you to see from far away if it is occupied) the secretary problem doesn't have this problem because the occupied ones simply don't show up so you can easily count them.

@VincentFarrugia 4 года назад

0:33 Prof J. Grime subtle reference is subtle :)

@PUMPADOUR 8 лет назад

It is not as much as mathematical problem, but a cultural one.

@Joaking91 8 лет назад

+PUMPA DOUR Im really interested in knowing how it is a cultural one. I mean you can replace the toilets with papers with a random number printed on the side facing the table, and asked to pick the largest number under the same circumstances.. and the math would work, with no culture involved in it whatsoever.

@PUMPADOUR 8 лет назад

Joaking Some cultures have more dirty toialets than others. A fact. Compare India to Singapore in hygiene - preaty amazing. UK people are on the dirty side too...

@Joaking91 8 лет назад

Uhm... well yeah that's correct but its just the set up man. If a person wanted the dirtiest toilet of the bunch, under the same rules, the strategy would apply, and the strategy is derived using math, not sociology.

@MichaelSacchi 8 лет назад

+Joaking Sometimes people miss the point. Sometime the point actively goes after them, but they duck and avoid it so they are missed. And that is a cultural problem :)

@fergochan 8 лет назад

+Michael Sacchi (signaleleven) I see people missing the point in so many of these videos. People both can't imagine using the technique for anything other than precisely the situation described, and try to poke holes in it by describing slightly different situations that they've experienced. It's kind of sad actually.

@jejez2424 8 лет назад

what happens if the cleanest toilet is in the first 37%

@Joaking91 8 лет назад

+jejez2424 This problem is statistical in nature, it can fail, but you're assured the best chances of finding the best toilet. I would myself settle with the first acceptable toilet i can find and forfeit the best one.

@stevenbee3301 8 лет назад

+jejez2424 i'm thinking about this too. So we must look at the rest of the toilet and take the last toilet?

@NetAndyCz 8 лет назад

+jejez2424 you go back in the line and hope the person who got in did not make too much mess in there. +Steven Bee Yes, but there is only about 37% chance the best toilet was there, so you have 63% chance you will encounter better toilet sooner than that.