explain xkcd - User contributions [en]

966: Jet Fuel

2021-11-23T14:11:34Z

172.69.68.106: /* Explanation */

{{comic
| number = 966
| date = October 19, 2011
| title = Jet Fuel
| image = jet_fuel.png
| titletext = The 'controlled demolition' theory was concocted by the government to distract us. '9/11 was an inside job' was an inside job!
}}

==Explanation==
This is another one of the "[[My Hobby]]" series, where [[Randall]] tells about a strange hobby. This comic is a reference to the "{{rw|9/11}} {{w|9/11 truther|Was An Inside Job}}" theory that the {{w|World Trade Center (1973–2001)|World Trade Center}} in {{w|New York City}} was blown up by a "controlled demolition". This is a fairly {{rw|9/11#Molten_steel_was_found_in_the_basement_seven_weeks_later_and_jet_fuel_can.27t_melt_steel_beams|common argument}} that is seen on the internet.

[[Hairy]]'s statement that "jet fuel can't burn hot enough to melt steel" references a common argument used by conspiracy theorists in references to the attacks. The official investigation concluded that the combination of the impact of the jets and the subsequent fire sufficiently compromised the structural steel beams of the towers that they lost integrity and collapsed. People who do not accept this conclusion frequently insist that the flame temperatures resulting from burning jet fuel is less than the melting point of steel, and so argue that the official explanation must be wrong, supporting their argument that the towers were deliberately brought down by explosives, planted by some conspiracy.

This argument has been {{rw|9/11#Molten_steel_was_found_in_the_basement_seven_weeks_later_and_jet_fuel_can.27t_melt_steel_beams|frequently refuted by experts}}, on a number of grounds. No fuel has a single burning temperature, the temperature of any given flame depends on a number of factors, which can be hard to predict in uncontrolled situtions. In addition, multiple fuels could have contributed to the fire, including not only the jet fuel but also flammables inside the building, and even metals (such as aluminum) that would have been pulverized and dispersed by the impact. Importantly, it is not necessary for beams to melt in order to collapse a building. Metals lose much of their structural strength well below their melting point. If enough beams were sufficiently weakened, they would fail under the weight of the building, putting more pressure on the remaining beams, which would then be likely to fail, and so on.

Cueball, however, doesn't argue with Hairy's premises, but instead takes a different tack, by appealing to a completely different conspiracy theory, concerning {{rw|Chemtrail|chemtrails}}. The Chemtrails conspiracy theory claims that the {{w|Contrail}}s left behind aircraft contain mind-control agents planted by the US Government (or any other government, {{w|reptiloids}}, {{w|Freemasons}}, etc.), which are used to drug the population en masse. Cueball operates under the assumption that this theory is true, and points out that this means typical passenger jets would be equipped with containers of these drugs, which could potentially burn at a high temperature. Because these drugs are entirely hypothetical, no assumption about them can possibly be disproven. This puts Hairy in a position of either having to argue against the chemtrail conspiracy theory, while arguing for a {{rw|9/11}} conspiracy theory or admit that there are factors he can't account for. This is unlikely to shake Hairy from his beliefs, but Cueball appears to find it entertaining to force a conspiracy theorist to confront the contradictions between conspiracy theories.

The title text is the natural "double down" on a theory which says that the conspiracy theory itself was concocted by the government and was supposed to distract from the truth, a parodic theory already seen in ''South Park'' episode {{w|Mystery of the Urinal Deuce}}.

==Transcript==
:[Hairy throws his arms out as he talks to Cueball, who answers while lifting a hand palm up.]
:Hairy: 9/11 was an inside job! Jet fuel can't burn hot enough to melt steel!
:Cueball: Well, remember — jet fuel wasn't the only thing on those planes. They would've also carried tanks full of the mind-control agents airliners use to make chemtrails.
:Cueball: Who ''knows'' what temperature that stuff burns at!
:Hairy: Whoa.
:Hairy: Good point!

:[Caption below the panel:]
:My Hobby: Playing conspiracy theories off against each other.

==Trivia==
For those wondering: it is true that kerosene does not burn hot enough in air to ''melt'' steel, but it does burn hot enough to cut the steel's supporting strength roughly in half, which is more than enough to collapse a building weighing thousands of tons. (Although standard engineering practice is to use a safety factor of three, and a safety factor of two is sufficient to allow for a 50% reduction in strength, over half of the columns in the two towers were severed in the initial impact, increasing the stress on the remaining columns.)

Cueball messing with {{rw|9/11|9/11 truther conspiracy theorists}} was also the subject of [[690: Semicontrolled Demolition]], and in [[496: Secretary: Part 3]] Black Hat claims the Twin Towers never actually collapsed. Chemtrails are mentioned again later in [[1677: Contrails]] and [[1803: Location Reviews]].
{{comic discussion}}

[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Hairy]]
[[Category:My Hobby]]
[[Category:Conspiracy theory]]
[[Category:9/11]]

Talk:2536: Wirecutter

2021-11-03T16:42:43Z

172.69.68.106:

Note: they don't say they tried out a large number of ''religions'' but a large number of '''belief systems'''. This could include things like "Libertarianism" or "Monarchists". (By CWALLENPOOLE, but not signed in.)
:But the picture of the article title says “The Best Religion” [[Special:Contributions/108.162.216.233|108.162.216.233]] 20:31, 1 November 2021 (UTC)

The phrase "highly controversial" should not be used in the explanation. For the record, I am opposed to the things listed in that sentence and my objection is not based in a desire to defend them. Religion itself might be said to be "highly controversial" so the use in the last sentence is both superfluous and biased. [[Special:Contributions/172.70.82.53|172.70.82.53]] 00:34, 2 November 2021 (UTC)

I really want this article to be real. ----Dave
: Me too. I did something similar in my early 20s, and feel such an article honestly done would be a great help to many. In fact, the current description is slightly inaccurate- in that even lifelong practitioners, do usually have a wandering time in early adulthood if not given direction. Such an article would give some direction.[[User:Seebert|Seebert]] ([[User talk:Seebert|talk]]) 15:03, 2 November 2021 (UTC)

The major problem with trying multiple religions is that to fully test a religion you need to die - and most people only die once, with the ability to die multiple times being exclusive feature of small number of religions. -- [[User:Hkmaly|Hkmaly]] ([[User talk:Hkmaly|talk]]) 04:49, 2 November 2021 (UTC)
:I ain't mad Hkmaly, but the idea that a religion's primary purpose is to promote a vision of the afterlife is alien to a lot of religions (including my own flavor of Judaism), whose policy on the hereafter is "afterlife, shmafterlife, pass the bagels." Hence also my edits toning down the "religions are about provable belief claims" rhetoric (eyeroll). ----Ben

It doesn't look like the search bar text says "search," but I can't make out what it actually says.--[[User:KrazyKat|KrazyKat]] ([[User talk:KrazyKat|talk]]) 06:33, 2 November 2021 (UTC)
:Maybe it says Seance, since for "seach" the high stoke from the H is missing. -- [[Special:Contributions/162.158.203.10|162.158.203.10]] 07:33, 2 November 2021 (UTC)
::or Sermon maybe, that would fit the theme
:Could be Search with large S and smaller caps for the rest? Anyone subscribe to the NYT and care to visit the actual WireCutter site to see the formatting? [[Special:Contributions/172.70.147.195|172.70.147.195]] 12:40, 2 November 2021 (UTC)
:: Don't need to be a subscriber to see the site. It says "Show me the best..." [[User:Paddles|Paddles]] ([[User talk:Paddles|talk]]) 13:26, 2 November 2021 (UTC)

I don't want to sound controversial but tithing would be a refreshing change comparing to current tax systems [[User:Tkopec|Tkopec]] ([[User talk:Tkopec|talk]]) 10:31, 2 November 2021 (UTC)
: Agreed- 10% is much less than the near 50% I'm paying when I figure it all in.[[User:Seebert|Seebert]] ([[User talk:Seebert|talk]]) 15:03, 2 November 2021 (UTC)
:: You really want to pay tithes AND taxes? [[Special:Contributions/108.162.249.63|108.162.249.63]] 18:54, 2 November 2021 (UTC)

Last night I was writing a huge thing about religions' almost universal reluctance to be 'tried out' (lestways allowing easy unsubscription at the end)  but on reflection, after a night's sleep, I'm wondering if they just had 70+ 'mystery shoppers' tasked to report back on one assigned 'product' each, their reports aggregated so this didn't matter too much (to the overall report-writers, at least). [[Special:Contributions/172.70.85.175|172.70.85.175]] 14:31, 2 November 2021 (UTC)

Also, the 'religious' wars metaphor extends quite easily to different platforms, yet (say) laptop reviews might compare a set of Windows vs a Mac or two (vs Chromebook, and maybe others) as options. And when it comes to keyboards, the QWERTY-Othodoxy and the Dvorak-Reformists both have bad (and untrue) things to say about each other, when 'enough time' with any given layout should be good enough to prosper in that. (That said, I had a {{w|Casio_FX-702P|programmable calculator}} from the '80s until it gave up the ghost some time post-Millenium, and I really did not get on with its ''alphabetical''-order keyboard all that time, perhaps because I was QWERTYing almost everywhere else.) [[Special:Contributions/172.70.85.175|172.70.85.175]] 14:31, 2 November 2021 (UTC)
:In the case of religions though, the wars are not allegorical, they are literal. Nothing else in human experience really compares to the effects of a religious war (except ''maybe'' our wars to support a certain socioeconomic idealogy). The impact of format wars don't even come close; even if you count Uranium VS Thorium. This comic doesn't really draw a ''comparison'' between reviewing religions & reviewing products; so much as it ''contrasts'' the enormous differences in how we approach the two subjects... <br />
:[[User:ProphetZarquon|ProphetZarquon]] ([[User talk:ProphetZarquon|talk]]) 17:41, 2 November 2021 (UTC)

(Also also: QWERTY with UK-layout is my own personal sub-sect, with occasional need to adapt to US-layout (physically printed keycaps and/or what the computer ''thought'' was plugged in) with " and # and ~ characters amongst the main jumbled up ones, and no easy £ access. Which wasn't actually as unnerving as being in the 'wrong' bit of Belfast, but had the same subtle note of discordant undertone to it until I shifted my mental gears or ideally corrected the situation satisfactorarily by configuration.) [[Special:Contributions/172.70.85.175|172.70.85.175]] 14:31, 2 November 2021 (UTC)

There's a book by John S. Dunne, ''The Way of All the Earth'', that advocates essentially trying out religions while keeping one foot in one's own (Dunne describes it as "crossing the abyss and crossing back"). [[Special:Contributions/162.158.74.158|162.158.74.158]] 17:17, 2 November 2021 (UTC)

Surprised no-one has yet mentioned this joke was done in almost exactly the same way on the UK satirical TV show TW3 in 1963 by David Frost (of later Frost/Nixon fame). --- jg https://www.youtube.com/watch?v=tRZWyfERiCc

I was just looking for psychological/psychiatrical papers that say something about the frequency of mental illnesses by religion. Maaaaaaaaaayyybeeeeeeeeee there is a religion that is clearly superior to other religions in that regard, and so government health officials could make a recommendation to change to a specific religion. :-P --[[Special:Contributions/162.158.88.57|162.158.88.57]] 10:58, 3 November 2021 (UTC)
:But then, illnesses (as well as the symptoms of the same illness) depend on the culture, so my sardonic idea was probably left unresearched...--[[Special:Contributions/162.158.91.106|162.158.91.106]] 12:23, 3 November 2021 (UTC)

Feels like there should be a line in there about how religion is itself often "that which determines what is valued" and therefore very hard to treat objectively. So, for example, if your religion taught that discipline was inherently good, you would think less of another religion that specifically warned against the dangers of excessive discipline. Meanwhile, a member of that religion might think YOUR religion was worse, because - according to the tenets of THEIR religion - you put TOO MUCH emphasis on discipline, while you think your emphasis is correct and THEY are wrong for not having it.
Now, granted, people might want different things from their technology - one person might want user-friendliness, another might value greater customizability - but religion is different in that it, in itself, informs our understandings of "what is valuable". It would be like if Apple users actively began extolling the benefits of user-friendliness BECAUSE they are Apple users and Apple itself is what taught them to value user-friendliness, while Linux users were originally indifferent but BECAME fans of customizability BECAUSE they used Linux. (And yes, there can be cult-like elements of both fandoms, but hopefully the distinction I'm drawing here is reasonably clear: religion tells you what is valuable, technology does not.)

(Also, why all the Judaism-specific stuff now?) --mezimm [[Special:Contributions/172.69.68.106|172.69.68.106]] 16:42, 3 November 2021 (UTC)

2533: Slope Hypothesis Testing

2021-10-26T12:54:27Z

172.69.68.106:

{{comic
| number = 2533
| date = October 25, 2021
| title = Slope Hypothesis Testing
| image = slope_hypothesis_testing.png
| titletext = "What? I can't hear--" "What? I said, are you sure--" "CAN YOU PLEASE SPEAK--"
}}

==Explanation==
{{incomplete|Created by a SCREAMINGLY SIGNIFICANT STAT STUDENT. Note: there's a name for when the bone in your ear pulls away after exposure to loud noise, could be thematic to reference it. There's probably also a name for the statistical mistake the comic demonstrates. Do NOT delete this tag too soon.}}
"Slope hypothesis testing" is a method of testing the significance of a hypothesis involving a scatter plot.

In this comic, [[Cueball]] and [[Megan]] are performing a study comparing student exam grades to the volume of their screams. Student A has the worst grade and softest scream, but Student B has the ''best'' grades and Student C the ''loudest'' scream. A trendline has been plotted, indicating a positive correlation between grades and volume...but the p-value is extremely high, indicating little statistical significance to the trend. P-value is based on both how well the data fits the trendline and how many data points have been taken; the more data points and the better they fit, the lower the p-value and more significant the data.

Megan complains about the insignificance of their results, so Cueball suggests having each student scream into the microphone a few more times (the three students are still there as they can be seen behind them. The three students looks like school kids, one of them is [[Science Girl]]).

Having the students scream again will not help though, because it only provides more data on the screaming without providing more data on its relation to exam scores, and is a joke around poor statistical calculations likely made in the field today. The p-value is incorrectly recalculated based on the increased number of measurements. Each student has exactly the same test scores (probably referencing the same datum as before) and have vocal volume ranges that don't drift far either (each seems to have a range of scream that is fairly consistent and far from overlapping). Megan is pleased by these results, but Cueball belatedly realizes this technique may not be scientifically valid.

Measuring data multiple times can be a way to increase its accuracy, but does not increase the number of data points with regard to another metric, and the horizontally clustered points on the chart make this visually clear.

The common p-value formulae assume the data points are statistically independent, that is, that the test score and volume measurement from one point don't reveal anything about those of the other points. By reusing the same exam scores separately across several measurements each, Cueball and Megan violate the independence assumption and invalidate their significance calculation. This is an example of pseudoreplication.

In current AI, there's a push toward "few-shot learning", where only a few data items are used to form conclusions, rather than the usual millions of them. This comic displays danger associated with using such approaches without understanding them in depth.

Additionally, a common theme in some research is the discovery of correlations that do not survive independent reproduction. This is because randomness with too few samples produces apparent correlations, and Randall has repeatedly made comics about this hopeful error.

In the title text, Megan and Cueball are trying to yell over each other, asking each other to speak up so they can be heard, presumably because they are having trouble hearing from the yelling experiment.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}
:[Three points labeled "Student A", "Student B" and "Student C" in a scatter plot with axes labeled "Stats exam grade" (60-100) and "Scream loudness (decibel)" (86-94) with a trend line]
:[A line goes from the trend line to a text box with the text:]
:β=1.94
:p=0.586

:[In a frameless panel, Megan (holding a piece of paper) and Cueball are facing each other with three kids in the background]
:Megan: Darn, not significant.
:Cueball: We need more data. Have them each try yelling in to the mic a few more times.

:[The same scatter plot as in the first panel except with more points for each of the students with slightly different decibel values, and the text in the text box changed to:]
:β=1.94
:p=0.037*
:<nowiki>*</nowiki>Significant!

:[Similar panel to the second one]
:Megan: Perfect!
:Cueball: Are you ''sure'' we're doing slope hypothesis testing right?

{{comic discussion}}

[[Category:Comics featuring Megan]]
[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Science Girl]] 
[[Category:Science]]
[[Category:Charts]]

Talk:2532: Censored Vaccine Card

2021-10-24T23:23:45Z

172.69.68.106:

Huh,his birthday was a week ago. Happy belated brithday![[Special:Contributions/162.158.48.115|162.158.48.115]] 04:03, 23 October 2021 (UTC)

What if this card is from the future and Cuedall is legitimately censoring his fourth dose.
[[Special:Contributions/162.158.255.43|162.158.255.43]] 22:38, 22 October 2021 (UTC) Running Gazelle

Numbers: Patient number is digits of pi after 3.1; 1138 and 2187 seem to be Star Wars references; 5309 is...Jenny? and 1729 is the Ramanujan-Hardy number.
[[User:Clam|Clam]] ([[User talk:Clam|talk]]) 23:16, 22 October 2021 (UTC)

I should be used to it by now (several decades of personal exposure to it) but I *still* have to double-take at dates in the illogical MM-DD-(YY)YY format. [[Special:Contributions/162.158.155.161|162.158.155.161]] 23:34, 22 October 2021 (UTC)

This is timely for me, I'm getting my booster tomorrow. [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 00:32, 23 October 2021 (UTC)

The date of birth corresponds to the date formerly on {{w|Randall Munroe|Randall's Wikipedia article}}, which never had an acceptable citation (only a now irretrievable wiki). The year is cited there, but not the rest. [[User:Yngvadottir|Yngvadottir]] ([[User talk:Yngvadottir|talk]]) 01:42, 23 October 2021 (UTC)
:The sleuths at English Wikipedia [https://web.archive.org/web/20171222052104/https://wiki.xkcd.com/wirc/index.php?title=Denizens&diff=prev&oldid=1315 retrieved the wiki]. The context does make it highly likely that this is Randall's real birth date. --[[Special:Contributions/108.162.219.105|108.162.219.105]] 21:04, 23 October 2021 (UTC)

Randall's pretty young. I wonder (it's none of my business, of course) whether he got a booster because his wife is a cancer survivor. [[User:Nitpicking|Nitpicking]] ([[User talk:Nitpicking|talk]]) 03:05, 23 October 2021 (UTC)

"This is the first comic including a sentence in Spanish." Well, it includes most of the sentence in Spanish, but it not a complete Spanish sentence, because it is heavily redacted. So there has not actually been a Spanish sentence in XKCD yet. [[User:Nutster|Nutster]] ([[User talk:Nutster|talk]]) 04:15, 23 October 2021 (UTC)

I've added the rest of the text to the transcript, but someone who knows wiki markup and/or transcript convention better than me should definitely revise the formatting. [[User:Esogalt|Esogalt]] ([[User talk:Esogalt|talk]]) 07:46, 23 October 2021 (UTC)

I was wondering why is Randal still using CVS, surely by now he has migrated to git? [[Special:Contributions/162.158.159.105|162.158.159.105]]
: Don't know if this is a joke about code repositories or not, but CVS is a pharmacy chain in the US. [[Special:Contributions/172.69.34.87|172.69.34.87]] 09:21, 23 October 2021 (UTC)

:: I've added this to the explanation. [[User:Esogalt|Esogalt]] ([[User talk:Esogalt|talk]]) 09:36, 23 October 2021 (UTC)

This feels very SCP-esque. [[Special:Contributions/172.69.214.17|172.69.214.17]] 17:31, 23 October 2021 (UTC)
: [REDACTED] [[Special:Contributions/172.69.68.106|172.69.68.106]] 23:23, 24 October 2021 (UTC)

It's interesting that the censor bars are parallel to the card, rather than the ''photo'' of the card, implying either a painstaking attention to detail (not implausible for Randall), or that he has actually physically blacked out the information on the card itself. [[User:Esogalt|Esogalt]] ([[User talk:Esogalt|talk]]) 17:37, 23 October 2021 (UTC)

Doesn't that say "Clinician #5309"? that would not refer to the store, but to the employee who administered the shot. [[User:Nitpicking|Nitpicking]] ([[User talk:Nitpicking|talk]]) 02:43, 24 October 2021 (UTC)

Wouldn't it be more appropriate to describe it as a redacted vaccination card rather than censored? [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 13:45, 24 October 2021 (UTC)
:If it has been wafted through the purifying smoke of a thurible (there's no indication it hasn't!) we could say it has been censered..? [[Special:Contributions/141.101.107.81|141.101.107.81]] 15:37, 24 October 2021 (UTC)

Talk:1427: iOS Keyboard

2021-10-22T19:56:16Z

172.69.68.106: reply to 42

XKCD references on the XKCD wiki? Who would've thought... [[Special:Contributions/141.101.104.197|141.101.104.197]] 06:58, 29 September 2014 (UTC)
:I'm so meta even this acronym.
:Just saying... [[Special:Contributions/108.162.217.125|108.162.217.125]] 07:58, 29 September 2014 (UTC)BK201

I believe that the ios word prediction is personalised based on your previous sentences. My Android autocomplete comes up with "Elementary, my feast of the United Kingdom", and "Toto, I've a feeling we're not going to Switzerland"... --[[User:Pudder|Pudder]] ([[User talk:Pudder|talk]]) 07:53, 29 September 2014 (UTC)
:I imagine it is, but it's still interesting to see the defaults before you've added much to the dictionary. I believe this is what Randall is up to. [[Special:Contributions/108.162.216.209|108.162.216.209]] 13:00, 29 September 2014 (UTC)

What about adding a reference to XKCD Questions[http://xkcd.com/1256/]? --[[User:Jkotek|Jkotek]]

Wasn't there XKCD comics about keyboard prediction starting from blank state? --[[User:JakubNarebski|JakubNarebski]] ([[User talk:JakubNarebski|talk]]) 09:57, 29 September 2014 (UTC)
:[http://xkcd.com/1068/] You're welcome. [[Special:Contributions/141.101.89.217|141.101.89.217]] 10:04, 29 September 2014 (UTC)

I thought some of the humor for the LoTR reference was the Gimli's dad was a character in The Hobbit. Obviously, Randall didn't work this in, but it could've affected his choice to feature this one in the comic [[User:Djbrasier|Djbrasier]] ([[User talk:Djbrasier|talk]]) 16:35, 29 September 2014 (UTC)

Given the outcome of the Scottish referendum on secession, it seems to me that the iOS-updated version of Wallace's quote is perfectly appropriate. --[[Special:Contributions/141.101.64.125|141.101.64.125]] 23:01, 30 September 2014 (UTC)

Wallace didn't fight the British, he fought the English. {{unsigned ip|141.101.98.19}}

Incomplete, anyone? Or is this wiki just goigo explain jokes Randall himself has made? It's probably the latter case, since nobody seems to have had a problem in four years. [[Special:Contributions/172.68.46.41|172.68.46.41]] 05:49, 12 May 2018 (UTC)

William Wallace's quote actually goes "They '''can''' take our lives, but they'll never take our freedom". [[Special:Contributions/172.68.253.149|172.68.253.149]] 01:59, 30 June 2019 (UTC)

Shouldn't the quote shown in the illustration at the top be explained too? It's not a movie per se, but still. --[[User:Theanswertolifetheuniverseandeverything|Theanswertolifetheuniverseandeverything]] ([[User talk:Theanswertolifetheuniverseandeverything|talk]]) 00:57, 29 March 2020 (UTC)
: Done. [[Special:Contributions/172.69.68.106|172.69.68.106]] 19:56, 22 October 2021 (UTC)