explain xkcd - User contributions [en]

217: e to the pi Minus pi

2020-11-18T00:29:43Z

172.69.63.203: /* Explanation */ added link

{{comic
| number = 217
| date = January 31, 2007
| title = e to the pi Minus pi
| image = e_to_the_pi_minus_pi.png
| titletext = Also, I hear the 4th root of (9^2 + 19^2/22) is pi.
}}

==Explanation==

''e'' is a mathematical constant roughly equal to 2.71828182846. ''π'' is another, roughly equal to 3.14159265359. Both are {{w|transcendental number}}s.

The first panel discusses {{w|Gelfond's constant|''e''''π''}} − ''π'', which is around 19.999099979 — very close to 20. [[Black Hat]] explains how he tricked a programming team into believing that ''e''''π'' − ''π'' really equals 20 — instead of just being weirdly close — thus that any noticeable deviation from 20 results from errors in the code. This made them waste a lot of time trying to find a nonexistent bug until they realized that Black Hat was lying (clearly they had not known him for very long, and clearly they weren't very knowledgeable in mathematics).

{{w|Floating point}} numbers are how computers store non-integer real numbers as decimals — or rather, in most cases, approximate them: infinite amounts of data would be required to represent most numbers in decimal form (exceptions are {{w|integers}} and {{w|terminating decimal}}s). The "floating-point handlers" would be the code performing the ''e''''π'' − ''π'' calculation.

ACM is the {{w|Association for Computing Machinery}}, sponsoring the {{w|ACM International Collegiate Programming Contest|International Collegiate Programming Contest}}. It is likely that it was this competition, in which Black Hat wasted his teams time, for which he got kicked out.

Some random facts about the math here:

* ''e''''π'' − ''π'' is an irrational number, but this is not a trivial fact. It was proven by {{w|Yuri Valentinovich Nesterenko}} in the late 20th century.
* The mysterious almost-equation is believed to be a {{w|mathematical coincidence}}, or a numerical relationship that "just happens" with no satisfactory explanation. It can be rearranged to (π + 20)i ≈ −1, so cos(ln(π + 20)) ≈ −1. Piling on a few more cosines gives cos(π cos(π cos(ln(π + 20)))) ≈ −1, which is off by less than 10−35!

The title text pokes fun at another coincidence: ∜(9² + 19²/22) ≈ 3.1415926525, close to ''π'' (deviating only in the 9th decimal place). The humor comes from the fact that ''π'' is {{w|transcendental number|transcendental}}. Transcendental numbers are numbers that cannot be expressed through basic arithmetic with integers; one cannot end up with the exact value for any transcendental number (including ''π'') by adding, subtracting, multiplying, dividing, exponentiating, and/or taking the nth root of any rational number, meaning the title text cannot possibly be true.

A much later comic, [[1047: Approximations]], puts forth quite a few more mathematical coincidences.

==Transcript==
:Cueball: Hey, check it out: eπ − π is 19.999099979. That's weird.
:Black Hat: Yeah. That's how I got kicked out of the ACM in college.
:Cueball: ...what?
:Black Hat: During a competition, I told the programmers on our team that eπ − π was a standard test of floating-point handlers -- it would come out to 20 unless they had rounding errors.
:Cueball: That's awful.
:Black Hat: Yeah, they dug through half their algorithms looking for the bug before they figured it out.

{{comic discussion}}
[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Black Hat]]
[[Category:Math]]
[[Category:Programming]]

Talk:2345: Wish on a Shooting Star

2020-08-14T18:18:10Z

172.69.63.203:

The other title text references:
https://meteoritecar.com/
https://alabamanewscenter.com/2017/11/30/on-this-day-in-alabama-history-meteorite-struck-oak-groves-ann-hodges/
https://en.wikipedia.org/wiki/Chelyabinsk_meteor
https://en.wikipedia.org/wiki/Tunguska_event

I often wish for cool lights in the sky tho...
: Not a bad wish to have. [[Special:Contributions/108.162.238.39|108.162.238.39]] 21:58, 12 August 2020 (UTC)
:: Though someone could think of wanting that, it wouldn't be anyone's first most important choice if you told them they could have a wish granted, unlike the things listed in the wish part of this diagram.--[[Special:Contributions/172.68.38.52|172.68.38.52]] 05:57, 13 August 2020 (UTC)

Am I the only person who wishes for radio noise? [[User:GreatWyrmGold|GreatWyrmGold]] ([[User talk:GreatWyrmGold|talk]]) 21:53, 12 August 2020 (UTC)
: Enough radio noise on the right frequencies could drown out talk radio, so ... you're not the only one wishing. [[Special:Contributions/108.162.238.39|108.162.238.39]] 21:58, 12 August 2020 (UTC)

Hams (and others) using meteor burst communications wish for ionized gas in the upper atmosphere. Now all we need somebody who wishes for infrasound so we get a proper subset.[[Special:Contributions/172.69.63.203|172.69.63.203]] 18:18, 14 August 2020 (UTC)

Meteors relative speed to Earth is surely high. However, note that Earth's orbital speed is 29.78 km/s, while the average orbital speed of meteoroids is 20km/s. In many cases it's therefore Earth which hits the meteors with it's high orbital speed ... -- [[User:Hkmaly|Hkmaly]] ([[User talk:Hkmaly|talk]]) 00:37, 13 August 2020 (UTC)
: A laughable claim, Mister Bond, perpetuated by overzealous teachers of science.
: (The unsigned comment above looked to be continued in the unsigned comment below, until I came here to day something and saw they were separate. Hey, people...) It would help if you could say "average at 20km/s ''whilst crossing Earth's orbit''...", because averaged across its entire track might include a lot of drifting around 'out there' and maybe zooming by (or not) during the perihelion segment. And then you only need to worry about retrograde ones (20+29.78, for a palpably mutual hit) and all kinds of other directions of cross, not just ones obviously aphelioning at 1AU in a relatively recently induced orbit that is about to end. Someone must have a table of (known/calculated) closing speeds, as well as directional components defined to Earth's frame-of-reference. [[Special:Contributions/141.101.98.132|141.101.98.132]] 04:08, 13 August 2020 (UTC)

With the valuable minerals contained within meteorites, it's reasonable that shooting stars could cause money/power. And to astrogeologists, there's success right there!
: If someone makes money off of selling a meteor they found, it's because they are a rare curiosity or of scientific value, not due to the minerals being of high value if they didn't come from a meteor. Though there are some historical cases of people without the technology to forge iron normally making iron tools from a meteor. However, someone finding the meteor on the ground later is a little different than the direct results of it falling (as the chart says things caused by "shooting stars" not "meteor rocks")--[[Special:Contributions/172.68.38.52|172.68.38.52]] 05:57, 13 August 2020 (UTC)

Gee, and here I thought he was making a pun to do with assassinating celebrities. -- [[Special:Contributions/172.69.68.157|172.69.68.157]]

Why did somebody write "Of course, as the title text makes clear, meteorites don't really land according to our designs and schedules"? It's equally valid to interpret it as meteorites being very precise and capricious on their revenge-wish-granting. -- Anonymous

There should be a reference to https://xkcd.com/1337/ as well. -- Myon

2342: Exposure Notification

2020-08-07T15:49:32Z

172.69.63.203: /* Explanation */ alternate "dark mode" explanation

{{comic
| number = 2342
| date = August 5, 2020
| title = Exposure Notification
| image = exposure_notification.png
| titletext = I don't see why everyone is so hungry for BAD news, but fine, I'll give in to feedback and add a dark mode.
}}

==Explanation==
{{incomplete|Created by a BOT THAT RECENTLY HAD CLOSE CONTACT WITH SOMEONE WHO HAS NOT TESTED POSITIVE FOR COVID. Do NOT delete this tag too soon.}}

During the coronavirus pandemic, several apps were developed to implement {{w|digital contact tracing}} by using one's location along with the location of others, or locationless device proximity detection, to notify someone if they had been potentially exposed to COVID-19. Participation is completely voluntary as data is self-reported, so such apps become more useful as more people use them. This normally only works in retrospect, as infected people are isolated, and the contacts notified after the positive test result. In this comic, a different type of app has been developed. Instead of notifying someone if they have been exposed to someone with COVID-19, the app produces notifications if they have been exposed to someone who has '''not''' tested positive. (Perhaps it also notifies the user if they have been exposed to a person who has tested positive, but if this is the case, it hasn't happened to the user in question yet.) This is much less useful because it is not possible to tell whether anyone has actually been near anyone who was infected, but rather annoys the user with excessive notifications. Also, being exposed to someone who has not tested positive is not good news, because it is still possible that the person might have COVID-19; it is simply less bad than being exposed to someone who has tested positive, but still worse than not being exposed to anyone.

Socially and psychologically, people being close to each other normally is a positive behavior. For a typical person, it could be considered a sad sign of our times if you needed an app to tell you whether you did right in social interactions and compliment you. (For [[:Category:Social_interactions|socially awkward people]], on the other hand, this could be a welcome development.)

[[File:GNOME Shell, GNOME Clocks, Evince, gThumb, GNOME Files at version 3.30 (2018-09) in Dark theme.png|thumb|right|The GNOME desktop environment in dark mode]]
{{w|Light-on-dark color scheme| Dark mode}} is a common feature in apps which allows users the options to have a darker user interface. The title text may refer to dark mode not in the sense of the color scheme but rather that receiving notifications bearing the bad news that you have been exposed to COVID-19 is "dark." Because nobody likes his current app, Randall decides to give in and create a dark mode, which would make his app much more desirable for users. Alternatively, it may just be that the developer is completely misunderstanding the user's actual needs. This would be consistent with creating an app that alerts the way this one did in the first place.

Randall has published similar "useless useful apps" in [[937: TornadoGuard]] (a tornado-alert app that has lots of great features, except it doesn't actually alert the user about tornadoes) and [[2236|2236: Is it Christmas?]] (a web page that correctly identifies most days as "not Christmas", but then fails to identify Christmas Day as Christmas, for a >99% "accuracy").

==Transcript==
:[Cueball standing, holding out his chiming smartphone to review alerts it has received.]

:Alert 1:43 PM
:'''Good news:''' You recently had close contact with someone who has not tested positive for COVID.
:Alert 1:38 PM
:'''Good news:''' You recently had close contact with someone who has not tested positive for COVID.
:Alert 1:36 PM
:'''Good news:''' You recently had close contact with someone who has not tested positive for COVID.
:Alert 1:31 PM
:'''Good news:''' You recently had close contact with someone who has not tested positive for COVID.
:[Caption below the panel:]
:No one likes my new COVID exposure notification app.

{{comic discussion}}
[[Category:COVID-19]]
[[Category:Comics featuring Cueball]]
[[Category:Smartphones]]

Talk:2342: Exposure Notification

2020-08-07T15:47:14Z

172.69.63.203: dark mode?

Is it dark mode as in low light UI or dark mode as in depressing? Or both [[Special:Contributions/198.41.238.106|198.41.238.106]] 21:24, 5 August 2020 (UTC)

I think the title text is using the term "dark mode" not in the sense of UI design but rather that COVID-19 is "dark" and if the app were to have a mode that did what other apps did and gave notifications for potential exposures (bad news) that would be a "dark mode." I have refrained from putting this in the explanation for now as I am curious if there are other interpretations.[[User:Nk1406|Nk1406]] ([[User talk:Nk1406|talk]]) 21:27, 5 August 2020 (UTC)

I see we were thinking the same thing. I will add it.[[User:Nk1406|Nk1406]] ([[User talk:Nk1406|talk]]) 21:27, 5 August 2020 (UTC)
: Actually I don't think that's what he meant at all. That would mean the developer was listening to user feedback. It seems more XKCD-like (and funnier) if the developer completely misunderstood the request and decided to spend a bunch of time adding a dark mode instead of what the user actually wanted. I'll add that as a possibility. [[Special:Contributions/172.69.63.203|172.69.63.203]] 15:47, 7 August 2020 (UTC)

Sheesh, why dance around the point, say it loud and proud— ‘’dark humor’’ --[[User:WurmWoode|WurmWoode]] ([[User talk:WurmWoode|talk]]) 21:59, 5 August 2020 (UTC)

reminds me of people who would freak out when a financial audit report included the standard wording "We find no evidence of fraud ...." [[User:Cellocgw|Cellocgw]] ([[User talk:Cellocgw|talk]]) 12:31, 6 August 2020 (UTC)

What's this about Stack Overflow? A link to an explanation of what happened to alienate users might be useful. [[User:LtPowers|LtPowers]] ([[User talk:LtPowers|talk]]) 12:36, 6 August 2020 (UTC)
:@LtPowers probably the mess when they tossed a moderator after she asked for clarification on some "don't be offensive" rule. (really, SO allowed groups dedicated to discussing the, ummm, finer points of interpreting religions, and then where "shocked, shocked, I tell you" to find that zealots had hissy fits) [[User:Cellocgw|Cellocgw]] ([[User talk:Cellocgw|talk]]) 13:29, 6 August 2020 (UTC)
::Huh. I thought SO was only for narrowly-tailored programming questions. Still, a link would be useful ''in the explanation'', in case I wasn't clear. [[User:LtPowers|LtPowers]] ([[User talk:LtPowers|talk]]) 13:42, 6 August 2020 (UTC)
::: @LtPowers The Stack Overflow website is part of a broader collection of sites in the Stack Exchange Network, which has many sites dedicated to various topics related both to technology and other topics.[[User:Nk1406|Nk1406]] ([[User talk:Nk1406|talk]]) 21:39, 6 August 2020 (UTC)
::I removed that bit, as it just seems like random trivia. [[Special:Contributions/172.69.34.144|172.69.34.144]] 20:49, 6 August 2020 (UTC)
:::I agree that it doesn't really belong in the explanation because it is quite a stretch to make a connection.[[User:Nk1406|Nk1406]] ([[User talk:Nk1406|talk]]) 21:39, 6 August 2020 (UTC)

There is no indication that the app is accessing any medical records, so I removed that section. The same self-reporting techniques that work in a normal contact tracing app would still work in this app.[[User:Nk1406|Nk1406]] ([[User talk:Nk1406|talk]]) 21:45, 6 August 2020 (UTC)

The dark mode comment could be about the actual dark mode, making a joke about how programmers don't actually respond to the user's wishes and also a joke about the fact that every app / OS nowadays needs a dark mode to be fancy. [[Special:Contributions/141.101.69.139|141.101.69.139]]

Should there be a Category for "useless useful apps"? [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 15:36, 7 August 2020 (UTC)

2336: Campfire Habitable Zone

2020-08-03T04:08:17Z

172.69.63.203: /* Explanation */

{{comic
| number = 2336
| date = July 22, 2020
| title = Campfire Habitable Zone
| image = campfire_habitable_zone.png
| titletext = Oh no, my marshmallow became tidally locked!
}}

{{incomplete|Created by a FIRE-PROOF ORBITING SMORE-MAKING ROBOT. Please mention here why this explanation isn't complete. Do NOT delete this tag too soon.}}

==Explanation==
This comic plays on the concept of the astronomic "habitable zone" applied at the scale of people sitting around a campfire.

The {{w|Circumstellar habitable zone|habitable zone}} for a star is the range of distances in which a planet might support liquid water, and hence life in the only form that we currently know of. Too close, and the amount of stellar radiation would be too great, causing water to boil. Too far, and the water would freeze. As an allusion to the "not too hot, not too cold, but ''just right''" of the {{w|Goldilocks_and_the_Three_Bears|children's story}}, although the varying quality invoked in that is as likely to be saltiness/sweetness as temperature, it is also commonly known as the "Goldilocks Zone".

For liquid water to actually exist, the planet itself must also have the right mass (in order to maintain a life-compatible atmosphere) and meet other requirements. For our sun, the habitable zone is estimated to range from about 0.38 to 10 astronomical units, where 1.0 is the distance from the sun to the Earth.

{{w|Marshmallow#Toasted_marshmallows|Marshmallow toasting}} is a popular camping activity in which people place a marshmallow (a soft, sugary blob made of gelatin and covered in corn starch) on a stick near a fire. As it cooks, the middle becomes gooey while the outside becomes crispy and perhaps slightly charred (maybe even burned), making it tastier via {{w|caramelization}} and the {{w|Maillard reaction}}.

In the context of the campfire, a similar "habitable zone" is posited to exist: close enough to the fire that the person can comfortably toast marshmallows, presumably on a stick of reasonable length - the ones shown seem to be about 1.5 times an arm's normal reach; yet far enough that the person is not uncomfortably hot, or even burnt by either direct contact with the flames, or by exposure to the radiant heat of the fire.

In the comic, Ponytail is sitting in the left habitable zone (marked in green), and appears to be enjoyably toasting a marshmallow. Cueball is sitting half outside the right habitable zone, too close to the fire, and appears to be getting scorched on his arm due to this. Fires [https://enjoythewild.com/how-hot-does-a-campfire-get/ can really get hot (2012 degrees F / 1100 degrees C) at times]! Megan is well outside the habitable zone on the right cool side. She is waving a marshmallow on a stick in vain, but presumably it will not toast, as it is too far from the fire, even farther from the fire than Cueball.

The title text introduces the concept of {{w|tidal locking}}. This is when one astronomical body synchronizes its rotation with its orbit around another, such that one side always faces the other body. The joke here is that if a marshmallow became tidally locked to the fire, then one side would become more and more cooked, perhaps burnt, while the other side never became toasted at all. This happens in real life, as in the case of Earth's moon, which always presents the same face to the Earth. The joke here may allude to the case of a marshmallow that has begun melting more than you realized and dripped down too far, so that it no longer responds when you rotate the roasting stick, and you'd better cut your losses and pull it out now before it drops into the fire pit.

==Transcript==
:[A campfire is in the middle of the panel in a white area with two areas shaded green to the left and right of the fire. There are also two white areas outside of these green areas. Ponytail is sitting normally on the ground to the left of the fire, with her body fully inside the left green area. She is facing the fire and is holding a stick in both hands. The stick has a marshmallow on the tip and she is holding it over the top of the flames of the fire. Cueball is sitting to the right near the fire, only half inside the green are. He is sitting sideways leaning away from the fire, holding one hand to his head, while his other hand seems to be ready to support him as he is leaning further away from the fire. The arm closest to the fire and his head seems to be very hot as three small smoke-like lines rises from Cueball. Megan is crouching to the right of Cueball, far from the fire outside the right green area. She is supporting herself on one knee and one foot. She is also holding a stick in both hands with a marshmallow on it. She is holding the stick inside the green area to the right of Cueball far from the fire. Four small lines above and below indicates that she is waving the stick up and down. The camp fire is built up of several logs on top of each other, with big flames above it, with smaller flames hanging loose in the air above the main flames. A small dead tree is to the far left and small rocks/stones lie along the ground all the way from left to right interspersed with grass tufts. Below the scene there is a label from which two curved arrows point to the two green areas.]
:Label: Habitable zone

:[Caption below panel:]
:Astronomers define the Campfire Habitable Zone as the region where you're far enough not to be burned but close enough to roast marshmallows.

{{comic discussion}}

[[Category:Comics with color]]
[[Category:Comics featuring Ponytail]]
[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Megan]]
[[Category:Astronomy]]
[[Category:Food]]

2322: ISO Paper Size Golden Spiral

2020-06-21T17:48:06Z

172.69.63.203:

{{comic
| number = 2322
| date = June 19, 2020
| title = ISO Paper Size Golden Spiral
| image = iso_paper_size_golden_spiral.png
| titletext = The ISO 216 standard ratio is cos(45°), but American letter paper is 8.5x11 because it uses radians, and 11/8.5 = pi/4.
}}

==Explanation==
{{incomplete|Created by a GRAPHICS DESIGNER. Please mention here why this explanation isn't complete. Do NOT delete this tag too soon.}}

This comic strip is about how to annoy graphics designers and mathematicians, much like [[590: Papyrus]] and [[1015: Kerning]].

An easy way to annoy many mathematicians is to make fanciful claims about the {{w|Golden Ratio}}. It's been claimed, with varying levels of credibility, to be detectable in many natural and humanmade situations, often with the dubious subjective claim that using the ratio in some particular way makes an image more "beautiful". The {{w|Golden Spiral}} is a spiral whose growth factor is this ratio; a common (though slightly geometrically inaccurate) way to illustrate the spiral is to draw curves through a set of squares whose side lengths shrink according to the Golden Ratio. The result looks rather like Randall's drawing here.

However, Randall hasn't used the Golden Ratio at all; he's just drawn a spiral (''not'' the Golden Spiral) through a common diagram showing the {{w|Paper_size#A_series|A Series}} of standard paper sizes, but in horizontal instead of portrait (this diagram is commonly drawn in portrait). These papers aren't squares at all, but rectangles whose side lengths shrink by a factor of the square root of 2. Additionally, the paper sizes shrink by a factor of one half instead of 2**-0.5, so the paper sizes should all be either even or odd. By mistaking the A Series for something connected with the Golden Ratio, ''and'' perpetuating the tradition of making dubious claims about the Golden Ratio, Randall has successfully annoyed both graphics designers and mathematicians.

===Title text===

The title text is a similarly themed joke, based partly on the fact that the US uses imperial units while much of the rest of the world uses SI units. The 11/8.5 ratio is the length/width ratio of {{w|Letter (paper size)|US Letter}} paper, which is 11 inches by 8.5 inches (another common size in the United States is US Legal, which is 14" by 8.5"). The value of pi/4 radians is indeed equal to 45 degrees, although Randall takes the cosine in one case and uses the raw angle in the other case in order to get a close coincidence of values. The width/length ratio of A Series paper ({{w|ISO 216}}) is exactly cos(45°), which is 1/sqrt(2). As for US Letter paper, 11/8.5 is not in fact close to pi/4, but it’s possible that Randall meant to write 8.5/11 instead of 11/8.5. To 4 decimal places, 8.5/11 = 0.7727 and pi/4 = 0.7854.

In reality, the usage of radians vs. degrees is not a geographic or political decision, but generally is delineated by profession. Most engineering and science fields measure angles in degrees or fractions of degrees (arcseconds, or even milliarcseconds in fields like astronomy), while mathematicians and physicists generally use radians. Civil engineers may refer to the slope of a road by its {{w|Grade (slope)|grade}}, which is commonly expressed in terms of the tangent of the angle to the horizontal (either as a percentage or a ratio); for angles up to ~10 degrees, this is close to the value of the angle in radians.

==Supplementary maths==
The difference between the "real" Golden Spiral squares and Randall's version is approximately either .2038 (for sqrt(2)-1.6180etc) or .08907 ((1/sqrt(2))-1.6180etc), depending on which way you're counting. Either way, the difference would be very noticeable.)

The spiral shown is a logarithmic spiral with a growth factor of sqrt(2), and if the center of the spiral is at the origin, it may be graphed with r = C*2^(θ/π), for any positive constant C.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

:[Caption inside panel:]
:The golden ratio is everywhere!

:[Picture of the ISO standard paper sizes (i.e. A1, A2, etc.) placed so that they fit together perfectly, overlaid with a spiral resembling that of the golden ratio]

:[Caption below panel:] 
:How to annoy both graphic designers and mathematicians

{{comic discussion}}
[[Category:Math]]
[[Category:Comics with color]]

Talk:1784: Bad Map Projection: Liquid Resize

2020-06-11T16:40:28Z

172.69.63.203:

I'm not too experienced with PhotoShop, but I think that the tool is a selective delete that he used on water bodies, so removing most of the water while maintaining relative shapes and sizes?
:Mostly just from the fact that India looks desiccated.
[[Special:Contributions/162.158.166.197|162.158.166.197]] 05:06, 11 January 2017 (UTC)Girish
::Australia is pretty mutilated, so I think the tool was used on land too [[Special:Contributions/162.158.178.111|162.158.178.111]] 05:55, 11 January 2017 (UTC)

Where are Laos and Cambodia missing? [[Special:Contributions/108.162.246.11|108.162.246.11]] 06:14, 11 January 2017 (UTC)
:It seems that Laos and Burma have been merged into one big county, as well as Cambodia and Thailand. Maybe they are just unnecessary details according to this map projection. [[Special:Contributions/162.158.238.22|162.158.238.22]] 16:39, 11 January 2017 (UTC)

The tool removes spaces of uniform color automagically. If you have big countries like India or Australia, they get caught by the algorithm as well. [[Special:Contributions/162.158.69.9|162.158.69.9]] 06:16, 11 January 2017 (UTC)

Can anybody figure out the projection before the application of the tool? [[Special:Contributions/108.162.219.232|108.162.219.232]] 06:58, 11 January 2017 (UTC)
:I think it is a Mercator projection that got mutilated. [[Special:Contributions/141.101.104.239|141.101.104.239]] 07:50, 11 January 2017 (UTC)
::I agree, it looks like a Mercator that Freddy Kruger got at.
Girish, [[Special:Contributions/162.158.166.197|162.158.166.197]] 09:02, 11 January 2017 (UTC)
:::I think if it was a Mercator, the bottom of Antarctica would be flat. To me, it looks like Winkel Tripel, with the odd angles in Alaska and the Russian Far East. [[User:Schroduck|Schroduck]] ([[User talk:Schroduck|talk]]) 15:02, 11 January 2017 (UTC)

I feel like there is some part of sarcasm in "unused blank spaces", as if it was Randall saying "You're right, why would anyone care about the oceans? There, I have removed them, problem solved.". Can anyone tie this to a recent event? Or maybe the joke is about improperly handling data, where you use a tool just because it's known to work well and for the sake of processing data, even if using in a given context doesn't make much sense. [[Special:Contributions/141.101.69.213|141.101.69.213]] 10:14, 11 January 2017 (UTC)
:I'm not sure about recent events, but "removing oceans" features prominently in one of Randall's [https://what-if.xkcd.com/53/ What If?] articles. {{unsigned ip|108.162.241.130}}

This map proves, once again, that it's good to be an archipelago. Philippines, FTW! [[Special:Contributions/172.68.54.58|172.68.54.58]] 13:59, 11 January 2017 (UTC)
:Hold your patriotic horses there, where did Palawan go? --[[Special:Contributions/162.158.138.10|162.158.138.10]] 12:24, 12 January 2017 (UTC)

Comics like these make me wonder how Randall preserves the XKCD visual style when working with content that is clearly not hand-drawn. [[User talk:AgentMuffin|~AgentMuffin]]

"This is a play on the common advice to young children to refrain from "running with scissors" to avoid physical accidents." <-- Does anyone else thing this is a bit of a stretch? {{unsigned ip|108.162.245.130}}
:Yes, I do :) [[User:Luckykaa|Luckykaa]] ([[User talk:Luckykaa|talk]]) 15:46, 12 January 2017 (UTC)
: absolutely. Running just refers to the algorithm. It's not meta in any way.[[Special:Contributions/162.158.58.45|162.158.58.45]] 16:29, 12 January 2017 (UTC)

This map centres on Africa, which has survived the distortion relatively unscathed. Might this be a dig at other projections that exaggerate the relative size of Africa? For example, Gall-Peters is called out in {{xkcd|977}} with a simple "I hate you".
--[[Special:Contributions/108.162.241.130|108.162.241.130]] 15:47, 13 January 2017 (UTC)
:Maybe but I think it is because all landmasses are more or less centered around Africa. By putting this center there is not need to show any of the Earths half-sphere with the paccific Ocean, which would anyway disappear completely. I think it would be more difficult for people to relate to a map that shows USA up Against China, than US up against Europe. And that may be an important factor when making such a comic. People need to know what they see and what has happened to appreciate the comic. But I'm sure he appreciated that it keeps Greenland and Australia much smaller then Africa, which is not the case for the mercator projection. --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 20:46, 17 January 2017 (UTC)

It seems to me that this comic is inspired by {{xkcd|1685}}, once again making humorous reference to using a Photoshop tool to accomplish an unrelated task. {{unsigned ip|108.162.215.130}}
:Agree. Will add [[1685: Patch]] to the explanation. --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 20:46, 17 January 2017 (UTC)

Can someone please explain the relevance of "political" in the title? Because I understood the resizing of the map to be related to unused blank political space, so that areas with little or no political "content" were cut away, which seems to run counter to what everyone else thinks. But then again, I know absolutely nothing about actual map resizing.
:"Political" is a type of map which focuses on showing locations of countries, usually by painting neighbouring ones in different colors.[[Special:Contributions/172.68.11.41|172.68.11.41]] 09:33, 24 January 2017 (UTC)

This page reads more like a review than an explanation. ★☆☆☆☆ [[Special:Contributions/108.162.212.227|108.162.212.227]] 10:16, 7 August 2017 (UTC)

Could someone add Tissot's Indicitracesisasoosaleez (correct spelling) onto the map as the title text shows? could someone do a reverse liquid resize to put it back to what it was before? [[Special:Contributions/172.69.63.203|172.69.63.203]] 16:40, 11 June 2020 (UTC)Bumpf

Talk:2317: Pinouts

2020-06-09T00:24:33Z

172.69.63.203: Comment re: 3.3eV/C

Can we add this one to a new category, "Comics that Randall makes just to screw with xkcd wiki contributors"? I can think of plenty of candidates for this category! [[User:Cosmogoblin|Cosmogoblin]] ([[User talk:Cosmogoblin|talk]]) 21:42, 8 June 2020 (UTC)

The claim that a coax has only one conductive part is incorrect. It has two. The pin is the inner conductor. The shield is the outer conductor. Without both it wouldn't work.

I'd also say that the claim at the top that a pin can have only one bit or one voltage of power at a time is incorrect. Power over Ethernet is a perfect example of power and data at the same time. There are also plenty of types of signals which transmit multiple bits at once. A simple example would be a signal using four voltage levels to transmit two bits simultaneously, but there are many more fancy analog encodings that use phase and frequency and other characteristics to transmit data. Plus, you can often included two signals on the same conductors. For example, ADSL combined a normal phone signal and a higher frequency data signal on the same lines. Also cable TV combined many signals on one set of conductors.

So, anyway, I'd remove the claim.
[[User:Mootstrap|Mootstrap]] ([[User talk:Mootstrap|talk]]) 23:00, 8 June 2020 (UTC)

I think "Pin Roulette" is a pun on [[wikipedia:Penn Jillette|Penn Jillette]], the talkative half of the [[wikipedia:Penn & Teller|Penn & Teller]] magic act, and maybe also a reference to [[wikipedia:chatroulette|chatroulette]]. [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 23:10, 8 June 2020 (UTC)
:Possible, but I'd stick with the simple explanation - that the "Pin Roulette" pin selects a random function when the connector's plugged in. [[Special:Contributions/108.162.245.64|108.162.245.64]] 23:18, 8 June 2020 (UTC)

In addition to pins being able to carry both data and power, or to carry multiple bits at a time, some pins function as clock signal pins that indicate bit boundaries rather than themselves carrying data; therefore I also think the claim should be either omitted or changed entirely.
[[User:Vaedez|Vaedez]] ([[User talk:Vaedez|talk]]) 23:33, 8 June 2020 (UTC)

Firstly, no [[1293|Soup]]? Secondly, [https://acronyms.thefreedictionary.com/GNDN GNDN] might easily have been referenced. Thirdly, would a pin made of solder melt, as pins connected to wires/boards ''by'' solder do not melt the solder (under proper range of use). [[Special:Contributions/141.101.107.158|141.101.107.158]] 23:38, 8 June 2020 (UTC)
:i think the implication is that it ''could'' melt, which is a trap--[[User:Vaedez|Vaedez]] ([[User talk:Vaedez|talk]]) 23:48, 8 June 2020 (UTC)

Perhaps we should add the actual usage of the pins to help those who actually want to know? [[Special:Contributions/162.158.62.245|162.158.62.245]] 00:08, 9 June 2020 (UTC)

Wouldn't 3.3eV/C be a tiny fraction of 3.3V, since a columb is a much greater value of charge than that of the electron?--[[Special:Contributions/172.69.63.203|172.69.63.203]] 00:24, 9 June 2020 (UTC)

2311: Confidence Interval

2020-05-26T05:33:05Z

172.69.63.203:

{{comic
| number = 2311
| date = May 25, 2020
| title = Confidence Interval
| image = confidence_interval.png
| titletext = The worst part is that's the millisigma interval.
}}

==Explanation==
{{incomplete|Created by a TERRIBLE MODEL. Please mention here why this explanation isn't complete. Do NOT delete this tag too soon.}}

Graphs of continuous functions' predicted values often show confidence intervals, a region (either shaded or marked with dotted lines, the latter used here) that indicates the margin of error for the prediction at any point. The joke in this comic is that the estimate has so much uncertainty that the confidence interval extends off the top and bottom of the chart, which in a real report would usually prevent it from being printed and require a rescaled chart to show it. Further, the title text suggests that these lines are not traditional 1 Sigma error intervals, but in fact 1/1000th of a sigma.

Furthermore, variations in the curve that are small compared the error bar typically can't be distinguished from errors. Therefore, the shape of the curve - and the entire graph in this example - is meaningless.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}
:(A curved graph. Two gray lines outside of the chart. X axis says “Fig. 2: Predicted Curve. Y axis is unlabeled)
:[Caption below the panel:]
:Science tip: If your model is bad enough, the confidence intervals will fall outside the printable area.
{{comic discussion}}
[[Category:Line graphs]]
[[Category:Tips]]
[[Category: Statistics]]

2311: Confidence Interval

2020-05-26T05:32:06Z

172.69.63.203:

{{comic
| number = 2311
| date = May 25, 2020
| title = Confidence Interval
| image = confidence_interval.png
| titletext = The worst part is that's the millisigma interval.
}}

==Explanation==
{{incomplete|Created by a TERRIBLE MODEL. Please mention here why this explanation isn't complete. Do NOT delete this tag too soon.}}

Graphs of continuous functions' predicted values often show confidence intervals, a region (either shaded or marked with dotted lines, the latter used here) that indicates the margin of error for the prediction at any point. The joke in this comic is that the estimate has so much uncertainty that the confidence interval extends off the top and bottom of the chart, which in a real report would usually prevent it from being printed and require a rescaled chart to show it. Further, the title text suggests that these lines are not traditional 1 Sigma error intervals, but in fact 1/1000th of a sigma.

Furthermore, variations in the curve that are small compared the error bar typically can't be distinguished from errors. Therefore, the shape of the curve - and the entire graph in this example - is meaningless.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}
:(A curved graph. Two gray lines outside of the chart. X axis says “Figure 2: Predicted Curve. Y axis is unlabeled)
:[Caption below the panel:]
:Science tip: If your model is bad enough, the confidence intervals will fall outside the printable area.
{{comic discussion}}
[[Category:Line graphs]]
[[Category:Tips]]
[[Category: Statistics]]

Talk:2311: Confidence Interval

2020-05-26T05:28:06Z

172.69.63.203:

What's a millisigma?
[[Special:Contributions/162.158.107.209|162.158.107.209]] 03:31, 26 May 2020 (UTC)Ven
Not an official scientific term - most likely referring to standard deviation. One standard deviation, or sigma, is the 68.3 % of values lying around the mean in a normal distribution. A millisigma in a standard deviation would be .0683 % of a normal distribution so that much variation would be bad? Not sure.
[[Special:Contributions/172.69.63.203|172.69.63.203]] 05:23, 26 May 2020 (UTC)

Talk:2311: Confidence Interval

2020-05-26T05:23:57Z

172.69.63.203:

What's a millisigma?
[[Special:Contributions/162.158.107.209|162.158.107.209]] 03:31, 26 May 2020 (UTC)Ven
Not an official scientific term - most likely referring to standard deviation. One standard deviation, or sigma, is the 68.3 % of values lying around the mean in a normal distribution. A millisigma in a standard deviation would be .000683?
[[Special:Contributions/172.69.63.203|172.69.63.203]] 05:23, 26 May 2020 (UTC)

Talk:2277: Business Greetings

2020-03-06T11:49:34Z

172.69.63.203:

This comic appears to be the only one, ever, that doesn't have mouseover text
[[Special:Contributions/162.158.146.160|162.158.146.160]] 05:15, 6 March 2020 (UTC)
:Maybe our mice are just broken. Purely coincidental, I'm sure. [[User:SDSpivey|SDSpivey]] ([[User talk:SDSpivey|talk]]) 05:49, 6 March 2020 (UTC)
::Or it is a change, to go with the time... --[[User:Lupo|Lupo]] ([[User talk:Lupo|talk]]) 08:07, 6 March 2020 (UTC)
:Technically [[404]] doesn't have an alt-text either. [[Special:Contributions/162.158.58.183|162.158.58.183]] 09:42, 6 March 2020 (UTC)
:I believe I've seen this before, where a comic _temporarily_ doesn't have title text. It may show itself yet. [[Special:Contributions/172.69.63.203|172.69.63.203]] 11:49, 6 March 2020 (UTC)

Maybe Randall posted it really late, staggered into bed, and will post the alt-text in the morning. I saw text but it was just the comic title. [[Special:Contributions/172.68.34.190|172.68.34.190]] 07:51, 6 March 2020 (UTC)

And, in case you were wondering, yes, [https://www.telegraph.co.uk/news/worldnews/asia/japan/10124306/Japanese-craze-for-eyeball-licking-leads-to-rise-in-infections.html eyeball licking is a thing] [[User:Sysin|Sysin]] ([[User talk:Sysin|talk]]) 08:22, 6 March 2020 (UTC)
: According to [https://www.snopes.com/fact-check/in-the-public-eye/ Snopes] the story about Japanese eye licking is not true. I've removed it from the explanation for now. If my information turns out to be false, feel free to add it back in. [[User:Bischoff|Bischoff]] ([[User talk:Bischoff|talk]]) 11:16, 6 March 2020 (UTC)

It's possible that mouse over / touch operation is seen as another form of physical contact, that goes along the comic.

I don't think we should overdo it with the "citation needed" joke or it will become dull. One instance in such a short explanation is definitely enough. [[User:Bischoff|Bischoff]] ([[User talk:Bischoff|talk]]) 11:22, 6 March 2020 (UTC)