explain xkcd - User contributions [en]

1053: Ten Thousand

2022-12-24T23:11:46Z

Cherryblossom: /* Explanation */ add missing full stop

{{comic
| number = 1053
| date = May 9, 2012
| title = Ten Thousand
| image = ten_thousand.png
| titletext = Saying 'what kind of an idiot doesn't know about the Yellowstone supervolcano' is so much more boring than telling someone about the Yellowstone supervolcano for the first time.
}}

==Explanation==
This strip argues that one shouldn't make fun of people for not knowing something that's considered common knowledge. The basic premise of the first panel is that, since people aren't born knowing ''anything'', everyone has to learn everything for the first time, at some point. If everyone ''eventually'' learns a given fact, there are an average of 10,000 people, in the US alone, who learn the fact for the first time each day.
The approximate rate of 10,000 people per day hearing about something for the first time is estimated by the birth rate of 4,000,000 people per year divided by 365 days per year, assuming that the birth rate is constant and that indeed ''everyone'' learns or gets the fact (or that those in the US who don't are about equal in number to those in other countries who do). The target age of thirty years is irrelevant in this calculation; the 10,000 number is simply equal to the number of newborns per day, or equivalently, the number of people who reach a given age each day. (The fact that not everyone lives to be that old, and some die younger, is not considered.)

The second panel points out that (certainly, for someone like Randall), teaching people an interesting fact for the first time is ''fun''. Mocking someone for their lack of knowledge makes them less likely to reveal that they don't know something, which means you don't get the opportunity to share in the experience as they discover it. Taking this approach is much more socially effective and generally enjoyable than mocking them for being ignorant. When Cueball learns that Megan doesn't know about the "Diet Coke and Mentos thing", he refers to her as "one of the lucky 10,000" who's experiencing it for the first time that day.

{{W|Diet Coke}} is a popular brand of sugar-free soda. {{W|Mentos}} is a brand of chewable mints. Famously, if you drop Mentos into a bottle of Diet Coke, the [https://en.wikipedia.org/wiki/Diet_Coke_and_Mentos_eruption soda will erupt quite aggressively], sending a fountain of soda 10 feet or more into the air. This interaction is widely beloved because it's dramatic and unexpected, while being generally safe, simple, and inexpensive to do (though it does make quite a mess, and should only be done outdoors). This effect appears to only happen with this specific type of soda and this specific mint, and is believed to result from a very particular interaction between the ingredients in the two, the texture of the mints, and the carbonation in the soda. This was explored, in some details, in a [http://www.youtube.com/watch?v=LjbJELjLgZg Mythbusters episode].

The Diet Coke and Mentos eruption has also been mentioned in a previous strip [[346: Diet Coke+Mentos]]. Both the eruption and this comic were referenced much later in [[https://what-if.xkcd.com/162/ What-If #162]], where the alt-text of the first image proclaims that "Some of the lucky 10,000 are less lucky than others", as demonstrated when [[Black Hat]] "helps" a Cueball with an overflowing Diet Coke by inserting Mentos into the opening.

The title text provides another, perhaps more emphatic example of how explaining a fact to a person for the first time is much more entertaining than just expressing annoyance about that missing knowledge. Here is a [http://www.youtube.com/watch?v=_PxDGiVQNg8 good video] about the {{w|Yellowstone supervolcano}}. Interestingly enough, both events includes some kind (although very different kind){{citation needed}} of eruption.

Supervolcanos are again mentioned in [[1159: Countdown]] and in [[1611: Baking Soda and Vinegar]].

This comic also appears in Randall Munroe's book ''[[How To]]'', in the introduction of the book, albeit in a modified form.

The value mentioned in the comic can be converted to the world data or country data by getting the birth rate(eg. x per day or x per year) and extrapolating down to per day, which for the world, based on data gotten in late 2022, would be about 4,00,000(140,000,000/365=383,561.643836≈400,000).

==Transcript==
:[Caption above the panel:]
:I try not to make fun of people for admitting they don't know things.
:[Caption right below said caption:]
:Because for each thing "everyone knows" by the time they're adults, every day there are, on average, 10,000 people in the US hearing about it for the first time.

:[A list of equations.]
:Fraction who have heard of it at birth = 0%
:Fraction who have heard of it by 30 ≈ 100%
:US birth rate ≈ 4,000,000/year
:Number hearing about it for the first time ≈ 10,000/day

:[Caption above the next panel:]
:If I make fun of people, I train them not to tell me when they have those moments.
:And I miss out on the fun.

:[Megan is standing. Cueball is walking, with his palm out.]
:Megan: "Diet Coke and Mentos thing"? What's that?
:Cueball: Oh man! Come on, we're going to the grocery store.
:Megan: Why?
:Cueball: You're one of today's lucky 10,000.

{{comic discussion}}
[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Megan]]
[[Category:Math]]

Talk:2687: Division Notation

2022-10-20T00:24:50Z

Cherryblossom:

Fun fact: In Poland, we don't write the long division like that; we just write A:B with the bar above. I was VERY confused the first time I saw that notation. [[Special:Contributions/172.70.246.235|172.70.246.235]] 21:03, 19 October 2022 (UTC)
:Unrelated to {{w|Polish notation}}, i presume? [[Special:Contributions/172.70.134.13|172.70.134.13]] 22:43, 19 October 2022 (UTC)Bumpf

For me, the version on the xkcd website has an additional line ("A/B: Software Engineer") that's not on this site. I think the comic might have been updated. Is anyone else seeing that? [[User:JBYoshi|JBYoshi]] ([[User talk:JBYoshi|talk]]) 23:20, 19 October 2022 (UTC)

For the Unicode one, I think it’s a reference to ⁄ (U+2044, fraction slash) or characters like ½, ¼, etc. - [[User:Cherryblossom|Cherryblossom]] ([[User talk:Cherryblossom|talk]]) 00:24, 20 October 2022 (UTC)

Talk:2687: Division Notation

2022-10-20T00:24:06Z

Cherryblossom:

Fun fact: In Poland, we don't write the long division like that; we just write A:B with the bar above. I was VERY confused the first time I saw that notation. [[Special:Contributions/172.70.246.235|172.70.246.235]] 21:03, 19 October 2022 (UTC)
:Unrelated to {{w|Polish notation}}, i presume? [[Special:Contributions/172.70.134.13|172.70.134.13]] 22:43, 19 October 2022 (UTC)Bumpf

For me, the version on the xkcd website has an additional line ("A/B: Software Engineer") that's not on this site. I think the comic might have been updated. Is anyone else seeing that? [[User:JBYoshi|JBYoshi]] ([[User talk:JBYoshi|talk]]) 23:20, 19 October 2022 (UTC)

For the Unicode one, I think it’s a reference to ⁄ (U+2044, fraction slash) or characters like ½, ¼, etc. - [[User:Cherryblossom000|Cherryblossom000]] ([[User talk:Cherryblossom000|talk]]) 00:24, 20 October 2022 (UTC)

1784: Bad Map Projection: Liquid Resize

2022-04-21T13:12:54Z

Cherryblossom: /* Explanation */ added [citation needed]

{{comic
| number = 1784
| date = January 11, 2017
| title = Bad Map Projection: Liquid Resize
| image = bad_map_projection_liquid_resize.png
| titletext = This map preserves the shapes of Tissot's indicatrices pretty well, as long as you draw them in before running the resize.
}}

==Explanation==
This is the first comic in the series of [[:Category:Bad Map Projections|Bad Map Projections]] presenting Bad map projection #107: The Liquid Resize. This turned into a series when [[1799: Bad Map Projection: Time Zones]] (#79), was released just a bit more than a month after this one.

There is no perfect way to draw a map of the world on a flat piece of paper. Each one will introduce a different type of distortion, and the best projection for a given situation is sometimes disputed. [[Randall]] previously explored 12 different projections in [[977: Map Projections]], and expressed his disdain for some types he sees as less efficient but whose users feel superior. None of them are truly perfect as any 2D map projection will always distort in a way the spherical reality, and a map projection that is useful for one aspect (like navigation, geographical shapes and masses visualization, etc.) will not be so for all the others. Local maps of smaller areas can be quite accurate, but the idea of both these map projection comics is to map the entire globe on a flat surface.

This comic suggests that there are many other projections than the 12 from the previous map projection comic, and Randall seems to have an entire list, of which at least 358 are "Bad Map Projections." The one presented here is #107 and is it called the "Liquid Resize." It is unclear if he includes the previous 12 in this list. Quite possibly he does, since all 2D projections of the surface of a 3D sphere will be bad in certain respects. (The next comic's projections ''Time Zones'' based on these, has #79 and could be concluded as being less bad than this one, which also seems realistic as this map looks more like a normal map projection, although it also has huge flaws).

The ''Liquid Resize'' map projection, however, is not only useless for most map applications -- as the size, shape, and position of most countries are quite distorted -- but its creation includes two steps which are outright counterproductive. If the list is sorted from best to worst it may be hard to find a worse projection method than this, so finding 106 projections better than this one seems realistic!

First, this method needs a planar map projection as its starting point, thus compounding the problems right off the bat. Planar projections are relatively accurate near the center but heavily distorted toward the edges. A famous example of a planar projection is the logo of the {{w|United Nations}}. Planar projections are basically only useful for 3D graphics rendering, if the user needs a quick, inexpensive way to store map textures that will later be attached to a sphere.

Second, the map uses [https://helpx.adobe.com/photoshop/using/content-aware-scaling.html Photoshop's content aware resizing tool], a very questionable choice.{{citation needed}} (Using a Photoshop tool for a task it is not intended for was also used in [[1685: Patch]] where a GNU patch tool was replaced with Adobe Photoshop's patch tool to compile code.) The content aware resizing tool resizes images by identifying what it thinks are important details and preserving these, while shrinking or stretching less detailed areas. For example, [http://knowyourmeme.com/photos/710073-content-aware-scaling when used on a face], the algorithm detects that the eyes and mouth are important details and tries to keep these in place, while stretching the skin around it. When applied to a map, this means that areas with lots of countries - and therefore lots of detail - such as Europe, West Africa, the Eastern Mediterranean and Central America/the Caribbean are relatively unchanged, while big countries like India, China and the US are very warped. The choices that the resizing tool makes are also dependent on the exact visual features of the original map, such as the choice of not having any topography or infrastructure drawn on, or not including a latitude/longitude grid, so what areas are deemed as unimportant is even more arbitrary than it would be on, say, a photographic picture of the Earth.

[http://knowyourmeme.com/memes/content-aware-scaling Bad content aware scaling] is already a meme. This projection does do a good job, however, of making almost every country clearly visible and indicating which countries are neighbors.
South America fits into Africa almost as it did in the era of the super-continent {{w|Pangaea}}.

{{w|Tissot's indicatrices}} are equally sized small circles overlaid on a globe to show the distortion of a particular map projection; if the map distortion distorts the shapes or areas of countries, it will do the same to the circles. The title text suggests that the shapes of Tissot's indicatrices would be pretty well preserved by the Liquid Resize transformation, 'as long as you draw them in before running the resize'. This is a joke. "Drawing them in before running the resize" means that a different projection would be generated (probably preserving the indicatrices themselves), making the use of the indicatrices meaningless, sort of like cheating. In fact by drawing them small enough there will be no resizing at all.

==Transcript==
:[Caption at the top of the panel:]
:Bad map projection #107:
:<big>The <big>Liquid Resize</big></big>
:A political map compressed using Photoshop's content-aware resizing algorithm to cut down on unused blank space

:[Below the caption there is a map of the world divided and colored by political boundaries, with outlines around each continent in black and around each country in dark gray. Antarctica is colored in light gray, bodies of water in white, and countries in pale shades of red, orange, yellow, green, blue, and purple. The map is heavily distorted, with Africa in the center and the other continents curving around it, approximating the bounds of a square with rounded corners. The oceans have been removed but also huge countries like the US, Australia, Brazil, Russia and especially India and Argentina have been heavily distorted while areas in the center with many smaller countries like Africa and Europe is almost unchanged.]

{{comic discussion}}

[[Category:Comics with color]]
[[Category:Bad Map Projections]]

Category:Cancer

2021-09-28T13:26:39Z

Cherryblossom: Undo revision 218607 by Cherryblossom (talk)

[[Randall]]'s (then, fiancée) wife was diagnosed with Stage III breast cancer in October of 2010. He immediately immersed himself in research of what cancer was, what treatments were like, etc. Every once in a while, his research, and happenings with his family bubble to the surface in the form of a comic.

*[http://blog.xkcd.com/2010/11/05/submarines/ This] is the first mention of the cancer.
*[http://blog.xkcd.com/2011/06/30/family-illness/ Here] is a blag post from Randall in June 2011 with an update.

[[Category:Comics by topic|Comics by topic]]

You may also notice that the tone of these cancer-themed comics slowly gets happier. This could be due to a number of factors. We can only hope this means [[Randall Munroe]]'s wife is getting better.

[[Category:Biology]]

Category:Cancer

2021-09-28T13:18:37Z

Cherryblossom: fix typo (blag → blog)

[[Randall]]'s (then, fiancée) wife was diagnosed with Stage III breast cancer in October of 2010. He immediately immersed himself in research of what cancer was, what treatments were like, etc. Every once in a while, his research, and happenings with his family bubble to the surface in the form of a comic.

*[http://blog.xkcd.com/2010/11/05/submarines/ This] is the first mention of the cancer.
*[http://blog.xkcd.com/2011/06/30/family-illness/ Here] is a blog post from Randall in June 2011 with an update.

[[Category:Comics by topic|Comics by topic]]

You may also notice that the tone of these cancer-themed comics slowly gets happier. This could be due to a number of factors. We can only hope this means [[Randall Munroe]]'s wife is getting better.

[[Category:Biology]]