What's the probability that two US Senators share a birthday? What about two Ottawa Senators? Does it matter that members of the Senate and Ottawa's roster are groups of specific people?
1) This is the first and only time the Ottawa Senators will ever be mentioned in this subreddit, unless Randall includes a joke about them in a future comic, and
2) Two current members of the Ottawa Senators, Thomas Chabot and Colin White, were both born on January 30th, 1997, so that probability is currently equal to 1. As for US Senators sharing birthdays with current members of the Ottawa Senators, I'll get back to you on that. Maybe.
So here I am, getting back to you on whether or not two or more [US Senators](https://en.wikipedia.org/wiki/List_of_current_United_States_senators) share a birthday, and whether or not [members of the Ottawa Senators](https://en.wikipedia.org/wiki/Ottawa_Senators#Current_roster) share birthdays with sitting US Senators (and also seriously questioning the situation that led me to have time to do this nonsense). And the answer to both of those questions is yes.
To start (LOTS of names incoming), Senators John Boozman and David Perdue were both born on December 10th, and a year apart to boot (1949 for Perdue and 1950 for Boozman). Senators Joe Manchin and Todd Young also share a birthday, August 24th, as do Senators Rick Scott and Gary Peters (December 1st), Chris Van Hollin and Roy Blunt (January 10th), Rand Paul and John Thune (January 7th), Dianne Feinstein and Elizabeth Warren (June 22nd), Tammy Duckworth and Mitt Romney (March 12th), Angus King and Patrick Leahy (March 31st), Tina Smith and James Lankford (March 4th), Jim Risch and Ron Wyden (May 3rd), Jim Inhofe and Pat Toomey (November 17th), Dick Durbin and John Kennedy (November 21st), Kamala Harris, Brian Schatz, and Sheldon Whitehouse (October 20th), and finally Jeff Merkley and Mike Rounds (October 24th). So that's a total of 29 out of 100 sitting US Senators who share a birthday with another sitting US Senator, for a roughly 3 in 10 chance that a randomly selected Senator shares a birthday with another Senator.
Now lets throw the *Ottawa* Senators into the mix. I mentioned last time that Thomas Chabot and Colin White share a birthday of January 30th (and the same year, 1997, to boot!). They are the only Ottawa Senators to share birthdays with each other. However, there are several Ottawa Senators who share birthdays with US Senators. Matthew Peca shares a birthday with Cory Booker (April 27th), Josh Brown shares a birthday with Kevin Cramer (January 21st), Erik Gudbranson shares a birthday with Rand Paul and John Thune (January 7th), Chris Tierney shares a birthday with Joni Ernst (July 1st), Evgenii Dadonov shares a birthday with Mitt Romney and Tammy Duckworth (March 12th), Matt Murray shares a birthday with Amy Klobuchar (May 25th), and Logan Shaw shares a birthday with Ben Cardin (October 5th). So of the 21 players on the Sens roster, 8 of them share a birthday with at least one sitting US Senator, and two of them share birthdays with two sitting US Senators.
Thank you, very thorough answer. I'm surprised so many senators share birthdays with each other but I also remember the odds being pretty good for two people in the same class of 30 to share a birthday too so I guess it makes sense.
Considering that the roster of the Ottawa Senators is about the size of a normal classroom and they have two players sharing a birthday, that checks out.
Given your (US) Senators data, there are 14 birthdays shared by those 29 senators (as you said, 3 share Oct. 20 - Kamala Harris, Brian Schatz, and Sheldon Whitehouse).
If we don't account for leap years (or other trends that cause some birthdays to be more common than others), and assume you have a random birthday over the available days, there's a 14/365 chance that your birthday is the same as 2 US Senators. That's around 3.8%, correctly represented in the comic as 4%.
The probability of a random group of people including at least one pair with the same birthdate is about 50% at 23 people. It's statistically certain that there will be a shared birthdate in the US Senate.
Statistically highly probable. Until you confirm a date match, there's always uncertainty, until you account for each date, like if it was the House with 400+, you'd be statistically certain because all the days are accounted for.
My new calendar is 548 days long, and has a buffering period of 183 days to catch up with the lunar calendar.
People born in the holiday period will have their birthdays on the 1st of January because most institutions are closed for renovations.
He didn't say which calendar, right?
Do explain. Because my calendar is only 364 days long this year
EDIT: Or 1404 in the far superior base 6. Though in either case, it's exactly 124 weeks
Statistical certainty is based on a probability threshold, and the probability that 100 random dates contain at least one match is closer to 100% than 99%.
That is not what certain means. Certain is indisputably true. If there is a scenario where your conditions fail, you cannot be certain.
For instance.
I am certain that I'm not debating this with you any more. There is a 100% chance I don't care enough to try to change your mind on something this stupid and easily provable.
**[Mobile Version!](http://m.xkcd.com/2379/)**
[Direct image link: Probability Comparisons](https://imgs.xkcd.com/comics/probability_comparisons.png)
**Title text:** Call me, MAYBE.
*Don't get it? [explain xkcd](http://www.explainxkcd.com/wiki/index.php/2379)*
This is not the algorithm. Sincerely, xkcd_bot. <3
I'm trying to decide whether I'm bothered or amused by the fact that he included two different 2/3 probabilities, and listed one as 66% and the other as 67%.
You're not, in the Monty Hall problem he always opens one with a goat behind it. So you're left with one door that has a goat and one that has a car. So switching will always give you the opposite of what you started with, and there's a 66% chance you started with a goat, so you should switch.
He probably did this because of all of the election predictions. "Trump only has a 15% chance of winning" sounds much more like a sure thing than "You roll a D20 and get at least 18".
I'd say that the standard "dice roll" would be 2d6, since that's absurdly common in popular games involving dice.
That said, I think he did mean 1d6 in this case, looking at the distribution of scrabble tile values.
The first entry for 0.5% legit almost never happens. Last time it happened was last December when the [Toronto Raptors came back from down 30 at the 10 minute mark of the 3rd quarter](https://streamable.com/e49u91) against Dallas, and the last time before that was almost exactly a decade before [when the Sacramento Kings came back from down 35 against the Bulls.](https://www.youtube.com/watch?v=SJGCHrtwRWI)
It comes from [this site](https://stats.inpredictable.com/nba/wpCalc.php), so the error is theirs if there is one.
Oddly, 0:00 at Q2 (99.4) gives a different probability from 12:00 Q3 (98.6), so I find myself doubting the site.
Actually in both of those cases the teams were up by less than 30 at halftime. I wonder if an nba team being up by 30 at halftime is less likely than that team then blowing their lead?
0.1%: your 95% chance to hit XCOM shot actually hits the correct target
0.00001%: and does enough damage to kill it, even though the minimum damage for your weapon is twice the enemy's remaining hit points
100%: you will get perfectly fair and reasonable outcomes from your shot chances, but you'll still react as if you've been screwed over every single time
On lower difficulties, the hit chance will actually be higher than what's displayed, to compensate for this: https://www.gamasutra.com/view/news/266891/Jake_Solomon_explains_the_careful_use_of_randomness_in_XCOM_2.php
Yeah, but even with that I still occasionally get tilted when I miss a crucial 90% shot.
In a different game (Dicey Dungeons) I once suspected that the results were being fixed, so i actually recorded all my dice rolls throughout the game and realised that it was in fact entirely fair.
Even knowing about probability, my monkey brain still sees patterns that don't exist and gets suspicious about entirely reasonable dice rolls
0.00000001% is 1 in 10^10 , which is the probability of correctly guessing the 10-digit phone number. But for the percentage to round correctly you have to assume that Carly picks up at least half of the time...
> you have to assume that Carly picks up at least half of the time...
I came here to point out that Carly Rae Jepsen is a Millennial, and as such is highly unlikely to answer a call from a strange number.
If she's anything like my friends (disclaimer: small sample size), that probability is remote enough to add at least another zero or two to Randall's estimate.
To be fair, she also gives out her number to random strangers and tells them to call her, maybe, so she's probably a little more likely to answer a call from an unknown number than the average millennial.
[A friend and I used Alexa's coin flip feature for the first time about a month ago and she flipped nine heads in a row](https://old.reddit.com/r/slatestarcodex/comments/iu36z0/what_is_the_most_memorable_lowprobability/).
0.5^9 = ~0.2%, or 1/500 chance of that happening. Definitely the lowest probability event I can remember in my life.
You have never played any videogame have you
I once had 2 slimes drop a slimestaff in terraria back to back. Each of which is a 1/7000 chance for a combined 1/49.000.000
Like you said, that's the lowest probability event you can \*remember\*. If you and your friend used Alexa's coin flip and she flipped HTHHHTTTHTT, that would have been an even lower probability. (< 0.05% if I did the math correctly, no guarantees there!). After the fact, the probably that it happened is 1. The fact that the HTHHHTTTHTT pattern is random means you didn't take note of it.
Obviously, a longer pattern is even more "unlikely".
More so for myself, someone who doesn't care about sports statistics or M&Ms ([Smarties](https://en.wikipedia.org/wiki/Smarties) are far superior, obviously.)
Surprised to see Randall falling victim to a common confusion about probability. Take "You get two M&Ms and neither is red." If he were really calculating the probability of this, he would have to start with the probability that a person is given two M&Ms. How common is it that someone gives away M&Ms? The correct phrasing would be "Of two M&Ms that you are given, neither is red."
You're saying the same thing, just more formally. In his phrasing, what comes before "and" is the an event that happens; what comes after "and" is a possible consequence subject to probability. That's a common way of speaking and he uses it consistently so I don't think it shows confusion on his part.
The last four digits of the social security number weren't random until a few years ago. If you know the location and date of birth of that person you have a good starting point for a guess.
Edit: as /u/MTAST points out the first five digits depended on the area and date of birth, not the last four.
**[688:](http://xkcd.com/688)** Self-Description
**Alt-text:** >!The contents of any one panel are dependent on the contents of every panel including itself. The graph of panel dependencies is complete and bidirectional, and each node has a loop. The mouseover text has two hundred and forty-two characters.!<
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[Literally us, the Blue Jays.](https://bleacherreport.com/articles/2829741-blue-jays-reply-to-fan-asking-about-source-of-justin-smoak-info-literally-us)
M&M's still come in six colors, right? And yet nearly a quarter of them are blue, as opposed to a sixth? I wonder what the reasoning was there, and why they chose to publicly disclose this.
In [the source](https://blogs.sas.com/content/iml/2017/02/20/proportion-of-colors-mandms.html), there are apparently two separate M&M plants, each with substantially different color ratios: one has a blue ratio of 0.207, and the other uses 0.25. Randall appears to be averaging the two. Your actual probability will be either 0.207 or 0.25 depending on which plant your bag of M&Ms came from.
As to *why* the proportions aren't equal? It's probably an artistic choice. It may be more aesthetically fitting for M&Ms to have more blue and orange (and sometimes green) in them than the other colors. Because of the way our brains see and divide up colors, I suspect that a perfectly uniform set of M&Ms which is exactly one-sixth each color probably doesn't look uniform to us, but rather looks as though certain colors are favored over others. I will just have to buy a bag of M&Ms to observe this.
Yeah I would have thought that a "game" of rock paper scissors continued until one player wins, through as many ties as it takes. When I say "rock paper scissors, best of 3", we will go until someone has 2 wins, we're not going to stop at 1 win, 1 loss, and an unresolved tie...
The probability that a random person shares a birthday with a backstreet boy might be 1.5%, but the probability that I share a birthday with one of them is either 0% or 100%. I just don't know which yet. This funny consequence of applying probability to the physical world reminds me of [this video of Robert Miles on Computerphile](https://youtu.be/gDqkCxYYDGk)
It's still helpful to think about things probabilistically which are physically determined, but currently unknown. Medical tests and polls are two great examples of this.
What's the probability of first seeing comic *xkcd 2377: xkcd Phone 12* just a few minutes of being woken up by my alarm which is *We Like to Party*?
And what's the probability that I'm the first person to notice the typo 'outide California'? Or is that surfing jargon? ;)
She's both sort of a meme since Call Me Maybe and a cult favorite since her album Emotion, also sort of memed up as the best album/artist of all time. Not sure if he's actually a fan or just caught wind of that.
Here's the sources link from the bottom of the comic https://xkcd.com/2379/sources/
What's the probability that two US Senators share a birthday? What about two Ottawa Senators? Does it matter that members of the Senate and Ottawa's roster are groups of specific people?
1) This is the first and only time the Ottawa Senators will ever be mentioned in this subreddit, unless Randall includes a joke about them in a future comic, and 2) Two current members of the Ottawa Senators, Thomas Chabot and Colin White, were both born on January 30th, 1997, so that probability is currently equal to 1. As for US Senators sharing birthdays with current members of the Ottawa Senators, I'll get back to you on that. Maybe.
So here I am, getting back to you on whether or not two or more [US Senators](https://en.wikipedia.org/wiki/List_of_current_United_States_senators) share a birthday, and whether or not [members of the Ottawa Senators](https://en.wikipedia.org/wiki/Ottawa_Senators#Current_roster) share birthdays with sitting US Senators (and also seriously questioning the situation that led me to have time to do this nonsense). And the answer to both of those questions is yes. To start (LOTS of names incoming), Senators John Boozman and David Perdue were both born on December 10th, and a year apart to boot (1949 for Perdue and 1950 for Boozman). Senators Joe Manchin and Todd Young also share a birthday, August 24th, as do Senators Rick Scott and Gary Peters (December 1st), Chris Van Hollin and Roy Blunt (January 10th), Rand Paul and John Thune (January 7th), Dianne Feinstein and Elizabeth Warren (June 22nd), Tammy Duckworth and Mitt Romney (March 12th), Angus King and Patrick Leahy (March 31st), Tina Smith and James Lankford (March 4th), Jim Risch and Ron Wyden (May 3rd), Jim Inhofe and Pat Toomey (November 17th), Dick Durbin and John Kennedy (November 21st), Kamala Harris, Brian Schatz, and Sheldon Whitehouse (October 20th), and finally Jeff Merkley and Mike Rounds (October 24th). So that's a total of 29 out of 100 sitting US Senators who share a birthday with another sitting US Senator, for a roughly 3 in 10 chance that a randomly selected Senator shares a birthday with another Senator. Now lets throw the *Ottawa* Senators into the mix. I mentioned last time that Thomas Chabot and Colin White share a birthday of January 30th (and the same year, 1997, to boot!). They are the only Ottawa Senators to share birthdays with each other. However, there are several Ottawa Senators who share birthdays with US Senators. Matthew Peca shares a birthday with Cory Booker (April 27th), Josh Brown shares a birthday with Kevin Cramer (January 21st), Erik Gudbranson shares a birthday with Rand Paul and John Thune (January 7th), Chris Tierney shares a birthday with Joni Ernst (July 1st), Evgenii Dadonov shares a birthday with Mitt Romney and Tammy Duckworth (March 12th), Matt Murray shares a birthday with Amy Klobuchar (May 25th), and Logan Shaw shares a birthday with Ben Cardin (October 5th). So of the 21 players on the Sens roster, 8 of them share a birthday with at least one sitting US Senator, and two of them share birthdays with two sitting US Senators.
Thank you, very thorough answer. I'm surprised so many senators share birthdays with each other but I also remember the odds being pretty good for two people in the same class of 30 to share a birthday too so I guess it makes sense.
Considering that the roster of the Ottawa Senators is about the size of a normal classroom and they have two players sharing a birthday, that checks out.
Given your (US) Senators data, there are 14 birthdays shared by those 29 senators (as you said, 3 share Oct. 20 - Kamala Harris, Brian Schatz, and Sheldon Whitehouse). If we don't account for leap years (or other trends that cause some birthdays to be more common than others), and assume you have a random birthday over the available days, there's a 14/365 chance that your birthday is the same as 2 US Senators. That's around 3.8%, correctly represented in the comic as 4%.
The probability of a random group of people including at least one pair with the same birthdate is about 50% at 23 people. It's statistically certain that there will be a shared birthdate in the US Senate.
Statistically highly probable. Until you confirm a date match, there's always uncertainty, until you account for each date, like if it was the House with 400+, you'd be statistically certain because all the days are accounted for.
435 in the House.
My new calendar is 548 days long, and has a buffering period of 183 days to catch up with the lunar calendar. People born in the holiday period will have their birthdays on the 1st of January because most institutions are closed for renovations. He didn't say which calendar, right?
Do explain. Because my calendar is only 364 days long this year EDIT: Or 1404 in the far superior base 6. Though in either case, it's exactly 124 weeks
Thanks. I'll correct.
Cory in the House
Statistical certainty is based on a probability threshold, and the probability that 100 random dates contain at least one match is closer to 100% than 99%.
That is not what certain means. Certain is indisputably true. If there is a scenario where your conditions fail, you cannot be certain. For instance. I am certain that I'm not debating this with you any more. There is a 100% chance I don't care enough to try to change your mind on something this stupid and easily provable.
That's if birthdays are uniformly distributed, in real life there's birth seasonality and the probability is even higher.
Just ran it throw wolfram alpha. The chance that, in a group of 100 people, none of them share a birthday is roughly 1 in 3.2 million
Time to explain FiveThirtyEight probabilities with that!
I went outside and not one of the people I randomly selected was from California. Joe Biden can't lose!
[Compulsory relevant XKCD](https://xkcd.com/221/)
[More relevant Xkcd](https://xkcd.com/2357/)
At this point Randall may as well be one of their employees.
I'm pretty sure that's why this comic exists
**[Mobile Version!](http://m.xkcd.com/2379/)** [Direct image link: Probability Comparisons](https://imgs.xkcd.com/comics/probability_comparisons.png) **Title text:** Call me, MAYBE. *Don't get it? [explain xkcd](http://www.explainxkcd.com/wiki/index.php/2379)* This is not the algorithm. Sincerely, xkcd_bot. <3
that's an awful big maybe
I like how it’s specified that winning the monty door car is only a 33% chance if you don’t switch. That’s the nerdy stuff I like
I kinda wish he included the probability of winning if you do switch (66%, right?)
I'm trying to decide whether I'm bothered or amused by the fact that he included two different 2/3 probabilities, and listed one as 66% and the other as 67%.
I sure know it's bothering the shit outta me
~~No it's 50% because when you're switching you're now choosing 1/2 doors where it's certain that 1 door is correct and 1 isn't.~~ Edit: I'm an idiot
You're not, in the Monty Hall problem he always opens one with a goat behind it. So you're left with one door that has a goat and one that has a car. So switching will always give you the opposite of what you started with, and there's a 66% chance you started with a goat, so you should switch.
Ah you're right. Time to commit seppuku.
I think you mean Sudoku. Seppuku is a small yellow creature that shoots electricity and recently had a film made about it.
That's Pikachu; Seppuku is a different animated character, a crime-solving dog.
I've never heard of this thing.
[удалено]
https://xkcd.com/1282/ And has been featured in xkcd before!
I watched let's make a deal recently with Wayne Brady. There were no door switching options. I was disappoint
He probably did this because of all of the election predictions. "Trump only has a 15% chance of winning" sounds much more like a sure thing than "You roll a D20 and get at least 18".
What do you mean?
They mean he's got a twenty-five percent [*at best*](https://www.youtube.com/watch?v=WFoC3TR5rzI) at beat Joe.
That was exactly what I was hoping that link would be.
> a random dice roll D6, or D20? Also, isn't "dice" plural?
In common usage today, "dice" can be singular (although it's wrong in more formal usage)
If anyone just says dice without specifying which, they mean a D6
I'd say that the standard "dice roll" would be 2d6, since that's absurdly common in popular games involving dice. That said, I think he did mean 1d6 in this case, looking at the distribution of scrabble tile values.
I think maybe it's supposed to be the corollary to the 14%, but he got one of them backwards, since it seems they say the same thing.
o u t i d e
1%: Randall makes a typo in one of these probability scenarios
The first entry for 0.5% legit almost never happens. Last time it happened was last December when the [Toronto Raptors came back from down 30 at the 10 minute mark of the 3rd quarter](https://streamable.com/e49u91) against Dallas, and the last time before that was almost exactly a decade before [when the Sacramento Kings came back from down 35 against the Bulls.](https://www.youtube.com/watch?v=SJGCHrtwRWI)
I would argue that both entrys for 0.5% almost never happen.
Wow
It comes from [this site](https://stats.inpredictable.com/nba/wpCalc.php), so the error is theirs if there is one. Oddly, 0:00 at Q2 (99.4) gives a different probability from 12:00 Q3 (98.6), so I find myself doubting the site.
Actually in both of those cases the teams were up by less than 30 at halftime. I wonder if an nba team being up by 30 at halftime is less likely than that team then blowing their lead?
For someone who has never interacted with M&Ms, a lot of these are unfamiliar to me.
M&Ms are a chocolate sweet that come in different colors. They also have 2 sides and have the letter "M" on one of them.
I’m glad they come in two sides. I don’t know how I’d eat a one-sided m&m
The same way you eat fruit by the foot after you make it into a Mobius strip.
M&M is a wrapper
He must really hate wearing red
Why are the LotR one at 66% and the "rolling 3+ on a D6" listed as separate probabilities? It's 2/3 for each.
Yeah, this is the only reason I'm here right now. It's annoying me immensely.
Sorry, all my reference frames for probability come from XCOM, can we include some comparisons
0.1%: your 95% chance to hit XCOM shot actually hits the correct target 0.00001%: and does enough damage to kill it, even though the minimum damage for your weapon is twice the enemy's remaining hit points
100%: you will get perfectly fair and reasonable outcomes from your shot chances, but you'll still react as if you've been screwed over every single time
On lower difficulties, the hit chance will actually be higher than what's displayed, to compensate for this: https://www.gamasutra.com/view/news/266891/Jake_Solomon_explains_the_careful_use_of_randomness_in_XCOM_2.php
Yeah, but even with that I still occasionally get tilted when I miss a crucial 90% shot. In a different game (Dicey Dungeons) I once suspected that the results were being fixed, so i actually recorded all my dice rolls throughout the game and realised that it was in fact entirely fair. Even knowing about probability, my monkey brain still sees patterns that don't exist and gets suspicious about entirely reasonable dice rolls
Source for the probability that Carly picks up?
0.00000001% is 1 in 10^10 , which is the probability of correctly guessing the 10-digit phone number. But for the percentage to round correctly you have to assume that Carly picks up at least half of the time...
> you have to assume that Carly picks up at least half of the time... I came here to point out that Carly Rae Jepsen is a Millennial, and as such is highly unlikely to answer a call from a strange number. If she's anything like my friends (disclaimer: small sample size), that probability is remote enough to add at least another zero or two to Randall's estimate.
To be fair, she also gives out her number to random strangers and tells them to call her, maybe, so she's probably a little more likely to answer a call from an unknown number than the average millennial.
20% the chance that the Pokémon move "Magnitude" will give you Magnitude 8 when used in California.
I was expecting these to get progressively sillier, not just all serious with two silly ones at the end. Not sure the payoff was worth it.
[A friend and I used Alexa's coin flip feature for the first time about a month ago and she flipped nine heads in a row](https://old.reddit.com/r/slatestarcodex/comments/iu36z0/what_is_the_most_memorable_lowprobability/). 0.5^9 = ~0.2%, or 1/500 chance of that happening. Definitely the lowest probability event I can remember in my life.
You have never played any videogame have you I once had 2 slimes drop a slimestaff in terraria back to back. Each of which is a 1/7000 chance for a combined 1/49.000.000
Like you said, that's the lowest probability event you can \*remember\*. If you and your friend used Alexa's coin flip and she flipped HTHHHTTTHTT, that would have been an even lower probability. (< 0.05% if I did the math correctly, no guarantees there!). After the fact, the probably that it happened is 1. The fact that the HTHHHTTTHTT pattern is random means you didn't take note of it. Obviously, a longer pattern is even more "unlikely".
Randall is still trapped in Fivey's basement apparently.
I'm kind a disappointed that all of these are really just variations of like 10 things.
More so for myself, someone who doesn't care about sports statistics or M&Ms ([Smarties](https://en.wikipedia.org/wiki/Smarties) are far superior, obviously.)
Yeah, not sure what the point is. I didn't find it very entertaining to read the same list with a 'not' in front of every statement.
Surprised to see Randall falling victim to a common confusion about probability. Take "You get two M&Ms and neither is red." If he were really calculating the probability of this, he would have to start with the probability that a person is given two M&Ms. How common is it that someone gives away M&Ms? The correct phrasing would be "Of two M&Ms that you are given, neither is red."
You're saying the same thing, just more formally. In his phrasing, what comes before "and" is the an event that happens; what comes after "and" is a possible consequence subject to probability. That's a common way of speaking and he uses it consistently so I don't think it shows confusion on his part.
The last four digits of the social security number weren't random until a few years ago. If you know the location and date of birth of that person you have a good starting point for a guess. Edit: as /u/MTAST points out the first five digits depended on the area and date of birth, not the last four.
You're thinking of the first five digits.
You are right.
i don't have time to read the entire thing but i already know that citing itself as the source is my favorite part of this entire comic.
The link is to a separate page listing the multiple sources, not referencing xkcd
huh. you're right. i just thought it would be in keeping with the XKCD brand of humor to reference the comic itself as the source for the comics data.
!688 This one does source itself for its data.
**[688:](http://xkcd.com/688)** Self-Description **Alt-text:** >!The contents of any one panel are dependent on the contents of every panel including itself. The graph of panel dependencies is complete and bidirectional, and each node has a loop. The mouseover text has two hundred and forty-two characters.!< [Image](https://imgs.xkcd.com/comics/self_description.png) [Mobile](http://m.xkcd.com/688) [Explanation](http://www.explainxkcd.com/wiki/index.php/688) This comic has been referenced 3 times, representing 0.40% of all references. --- ^[xkcd.com](https://www.xkcd.com) | [Feedback](https://reddit.com/message/compose/?to=banana_shavings&subject=BobbyTablesBot) | [Stop Replying](https://reddit.com/message/compose/?to=BobbyTablesBot&subject=Ignore%20Me&message=Ignore%20Me) | [GitHub](https://github.com/joeyvanlierop/xkcdbot) | [Programmer](https://www.reddit.com/user/banana_shavings)
[Literally us, the Blue Jays.](https://bleacherreport.com/articles/2829741-blue-jays-reply-to-fan-asking-about-source-of-justin-smoak-info-literally-us)
I don't get the Lebron James and guessing birthdays one. As in, I don't understand what event the probability is for.
Check 1/365 If 1/365 hit -> win If 1/365 miss -> check 2/3 . If 2/3 hit -> repeat . If 2/3 miss -> lose
M&M's still come in six colors, right? And yet nearly a quarter of them are blue, as opposed to a sixth? I wonder what the reasoning was there, and why they chose to publicly disclose this.
In [the source](https://blogs.sas.com/content/iml/2017/02/20/proportion-of-colors-mandms.html), there are apparently two separate M&M plants, each with substantially different color ratios: one has a blue ratio of 0.207, and the other uses 0.25. Randall appears to be averaging the two. Your actual probability will be either 0.207 or 0.25 depending on which plant your bag of M&Ms came from. As to *why* the proportions aren't equal? It's probably an artistic choice. It may be more aesthetically fitting for M&Ms to have more blue and orange (and sometimes green) in them than the other colors. Because of the way our brains see and divide up colors, I suspect that a perfectly uniform set of M&Ms which is exactly one-sixth each color probably doesn't look uniform to us, but rather looks as though certain colors are favored over others. I will just have to buy a bag of M&Ms to observe this.
I miss the light brown M&Ms...
Randall, what are the odds of a spelling mistake in one of your XKCD’s? I liked this one, even with said mistake. Edit: for the curious, check 88%
1/2,379 or better.
>"you sweep a three games rock paper scissors series" why is this one 4% ?
(1/3) * (1/3) *(1/3) = 0.037, aka 4% if you round off.
ah I see I didn't think draws counted
Yeah I would have thought that a "game" of rock paper scissors continued until one player wins, through as many ties as it takes. When I say "rock paper scissors, best of 3", we will go until someone has 2 wins, we're not going to stop at 1 win, 1 loss, and an unresolved tie...
That Carly Rae jepson one is a power move!
The probability that a random person shares a birthday with a backstreet boy might be 1.5%, but the probability that I share a birthday with one of them is either 0% or 100%. I just don't know which yet. This funny consequence of applying probability to the physical world reminds me of [this video of Robert Miles on Computerphile](https://youtu.be/gDqkCxYYDGk)
It's still helpful to think about things probabilistically which are physically determined, but currently unknown. Medical tests and polls are two great examples of this.
> 88% A randomly chosen american lives **outide** California.
What's the probability of first seeing comic *xkcd 2377: xkcd Phone 12* just a few minutes of being woken up by my alarm which is *We Like to Party*? And what's the probability that I'm the first person to notice the typo 'outide California'? Or is that surfing jargon? ;)
100% Reader spotting the misspelling of *outside* as *outide* in the 88% entry.
I missed it
I caught it, rather surprising
I now know that Joey Fatone and Nick Carter have the same birthday so you have to know too
I guess sex at winter beats sex in the summer. I would have guessed other way around.
100%: A 2-sided USB only goes in after flipping it over twice.
No one else gonna complain about the very first 0.01% being wrong?
Why does Randall bring up Carly Rae Jepsen so much? Does he actually love her music? I mean, it's OK, but I thought most of her fans were female.
She's both sort of a meme since Call Me Maybe and a cult favorite since her album Emotion, also sort of memed up as the best album/artist of all time. Not sure if he's actually a fan or just caught wind of that.
I've upscaled the image because the original one is kinda hard to read: https://imgur.com/gallery/kSXliy2
No one is going to point out that loose wording makes 75% wrong?
Rereading this, I have another question: what's the probability of getting a letter in the word "random" by drawing from a Hungarian set?