explain xkcd - User contributions [en]

1725: Linear Regression

2016-08-26T15:14:41Z

HiddenWindshield: Transcript

{{comic
| number = 1725
| date = August 26, 2016
| title = Linear Regression
| image = linear_regression.png
| titletext = The 95% confidence interval suggests Rexthor's dog could also be a cat, or possibly a teapot.
}}

==Explanation==

{{w|Linear regression}} is a method for modeling the relationship between two sets of data, assuming that the two have a linear correlation (as opposed to, say, a quadratic correlation or no correlation whatsoever). The model determines a "{{w|least squares|best-fit}}" line through a {{w|scatter plot}} of the datasets, together with a {{w|coefficient of determination}}, usually denoted ''r''2 or ''R''2. This is a number between 0 and 1, which indicates how close the points are to lying on a line. A value of 1 means perfect correlation, while values close to 0 indicate little or no correlation.

{{w|Constellation}}s are patterns created by linking the apparent positions of stars. One could create fake constellations by connecting assorted points.

In this comic, a set of data has had linear regression and some form of statistical analysis applied to it, indicating that there is insignificant correlation between the two. However, the data points are so widely-scattered that (as noted in the comic) it is easier to connect the data points in a constellation-like pattern than it is to determine whether the correlation is negative or positive (without looking at the trendline, of course). Because of this, [[Randall]] suggests we should be suspicious of any conclusions drawn from this data.

==Transcript==
{{incomplete transcript}}
Panel 1: A scatter plot with many dots and a slightly rising red line is presented. The bottom of the panel reads "R2=0.06" in red.

Panel 2: The same plot, but with new red lines making a constellation of a stick man holding a dog/teapot/cat/???. The bottom of the panel reads "REXTHOR, THE DOG-BEARER" in red.

Beneath both panels is the text "I don't trust linear regressions when its harder to guess the direction of the correlation from the scatter plot than to find new constellations in it."
{{comic discussion}}

6: Irony

2016-03-23T22:15:05Z

HiddenWindshield: It's vs. Its

{{comic
| number = 6
| date = September 30, 2005
| title = Irony
| image = irony_color.jpg
| titletext = It's commonly known that too much perspective can be a downer.
}}

==Explanation==
It must be part of the {{w|human condition}} that causes us to think that odd statements are sometimes more humorous than those supposed to be funny. [[Cueball]] makes a true statement, that his statement is not very funny. However, because he invoked {{w|irony}} and thus makes it self-referential, the sentence is now funny! The other guy (also a Cueball like character), producing a fake laugh, is probably not so sure that it is actually funny.

Now going meta: In 20,000 years, there might be no more humans on earth to find the irony funny any more. How ''ironic''! Alternatively, the barren landscape would have occurred regardless of whether someone made the joke, so ironically the cautionary tale is completely meaningless, although still funny.

This is the first [[xkcd]] comic showing stick figure people, which eventually becomes a defining characteristic of the future comic series. It is thus also the first comic with Cueball (and the first with [http://www.explainxkcd.com/wiki/index.php/Category:Multiple_Cueballs Multiple Cueballs]).

The "too much perspective" idea may reference the {{w|Technology_in_The_Hitchhiker's_Guide_to_the_Galaxy#Total_Perspective_Vortex|Total Perspective Vortex}} in {{w|The Hitchhiker's Guide to the Galaxy}}.

Self-references was already used again in [[33: Self-reference]], and [[:Category:Self-reference|again and again]], but never more famously than in [[688: Self-Description]].

==Transcript==
:[A panel only with text. The last text is written below a line in all capital letters.]
:When self-reference, irony, and meta-humor go too far
:A CAUTIONARY TALE

:[Cueball talks to to his Cueball-like friend.]
:Cueball: This statement wouldn't be funny if not for irony!

:[Cueball laughs at his own joke in front of his friend.]
:Cueball: ha ha
:Friend: ha ha, I guess.

:[Again a panel only with text.]
:20,000 years later...

:[Desolate badlands landscape with an imposing sun in the sky.]

==Trivia==
*This was the 9th comic originally posted to [[LiveJournal]].
**The previous was [[8: Red Spiders]].
**The next was [[9: Serenity is coming out tomorrow]].
*This comic kept its original title: "Irony"
*Original [[Randall]] quote: "Too much perspective can do that."
*This was one of the [[:Category:First day on LiveJournal|thirteen first comics]] posted to LiveJournal within 12 minutes on Friday September 30, 2005.
*This comic was posted on [[xkcd]] when the web site opened on Sunday the 1st of January 2006.
**It was posted along [[:Category:First day on xkcd|with all 41 comics]] posted before that on LiveJournal as well as a few others.
**The latter explaining why the numbers of these 41 LiveJournal comics ranges from 1-44.
*One of the original drawings drawn on [[:Category:Checkered paper|checkered paper]].
*First comic featuring [[Cueball]]

{{comic discussion}}
[[Category:Comics posted on livejournal| 09]]
[[Category:First day on LiveJournal| 09]]
[[Category:First day on xkcd]]
[[Category:Comics with color]]
[[Category:Checkered paper]]
[[Category:Comics featuring Cueball]]
[[Category:Multiple Cueballs]]
[[Category:Self-reference]]

1501: Mysteries

2016-01-25T05:08:46Z

HiddenWindshield:

{{comic
| number = 1501
| date = March 20, 2015
| title = Mysteries
| image = mysteries.png
| titletext = At the bottom left: The mystery of why, when I know I needed to be asleep an hour ago, I decide it's a good time to read through every Wikipedia article in the categories 'Out-of-place artifacts', 'Earth mysteries', 'Anomalous weather', and 'List of people who disappeared mysteriously'.
}}

==Explanation==
This comic shows a graph in which several "mysteries" are mentioned and placed on the graph according to how weird they are on the x-axis and the y-axis indicates whether [[Randall]] has an explanation or not for the mystery. Each item is listed in the [[#Table|table below]].

Items near the top-right corner (such as the {{w|Malaysia Airlines Flight 370|MH 370}} disappearance) are both mysterious and strange. Items near the bottom-left corner (such as Randall's absent-mindedness regarding ice cream) have a clear explanation and are not really strange either. Items near the top-left corner (such as the meaning of ''{{w|You're So Vain}}'') are mysterious but not really strange. Items near the bottom-right corner (such as the {{w|Dyatlov Pass incident}}) have a clear explanation but are quite strange.

The title text refers to the mystery of Randall staying up late to read Wikipedia articles, when he was already supposed to be asleep an hour ago. This is apparently not very unusual for him (see for instance [[214: The Problem with Wikipedia]]). And this mystery actually has an obvious explanation: Following up on an idea that eventually led to today's cartoon.

Some of these mysteries have already been explored in xkcd. See [[950: Mystery Solved]] where Randall "solves" Amelia Earhart, Lost Roanoke Colony, Jimmy Hoffa; [[593: Voynich Manuscript]]; and [[1400: D.B. Cooper]].

==Table==
*The X axis in the graph indicates weirdness.
**The table assumes that the item to the far left is 0% (not that weird) and the item to the far right is 100% (weird as hell).
*The Y axis indicates if Randall has an explanation.
**The table assumes that the item at the bottom is 100% (Randall has a clear explanation) and the item at the top is 0% (Randall has no explanation).

{| class="wikitable sortable"
!Entry
!Weirdness
!Explainability
!Further details
|-
|MH370
|100%
|0% 
|On 8 March 2014, {{w|Malaysia Airlines Flight 370}} cut off radio contact and diverted from its flight path with 227 passengers aboard, eventually heading over open ocean, eventually crashing in a remote part of the Indian Ocean. The disappearance remains without explanation, although parts were found on Reunion Island in July 2015.
|-
|Lead masks case
|99%
|12% 
|In 1966 two Brazilian atomicians were found dead on a hill top. No injuries. {{w|Lead Masks Case|Both were wearing lead masks}}.
|-
|Salish Sea feet
|96%
|31% 
|Over a dozen dismembered human feet {{w|Salish Sea human foot discoveries|were found}} between 2007 and 2014 on the coasts of the Salish Sea in British Columbia (Canada) and Washington (United States).
|-
|DB Cooper
|76%
|20% 
|{{w|D. B. Cooper}} was an airplane hijacker who jumped from a plane after successfully extorting a large ransom in 1971. The man's whereabouts remain unknown to this day, though [http://www.dailymail.co.uk/news/article-2401312/Parachute-used-hijacker-DB-Cooper-escape-stealing-200-000-goes-display.html some of the ransom money has been recovered]. Previously referenced in [[1400: D.B. Cooper]] which compares Cooper to film director {{w|Tommy Wiseau}}. Note that this "Mysteries" comic was published shortly after [http://www.reddit.com/r/IAmA/comments/2zdzik/tommy_wiseau_creator_of_the_room_and_the_new_tv/ Tommy Wiseau did a Reddit AMA.]
|-
|The WOW signal
|55%
|20% 
|The {{w|Wow! signal}} was a strong and clean radio transmission near 1420 MHz received by the Big Ear Radio Observatory at Ohio State University in 1977 that [http://www.universetoday.com/93754/35-years-later-the-wow-signal-still-tantalizes/ appears to have originated from interstellar space.] This is the strongest evidence to date of radio signals transmitted by extraterrestrial intelligent beings.
|-
|Mary Celeste
|70%
|43% 
|The ''{{w|Mary Celeste}}'' was a sailing ship found adrift off the {{w|Azores Islands}}, mysteriously abandoned yet otherwise undisturbed, in 1872. Most likely the crew abandoned ship, wrongly believing it was in danger. Its name has become a watchword for mysteriously abandoned ships.
|-
|UVB-76
|40%
|23% 
|{{w|UVB-76}} is a mysterious shortwave radio station, apparently originating from Russia, that has broadcast a monotonous buzz tone since 1982 with occasional other content.
|-
|Who Carly Simon is singing about in ''You're So Vain''
|9%
|4% 
|The ironically self-referential lyrics of the 1972 song include "You're so vain, you probably think this song is about you." There has been {{w|You%27re_So_Vain#Subject_of_the_song|much speculation}} regarding the person or persons to whom Simon was referring.
|-
|Zodiac letters
|62%
|62% 
|A set of letters were written by the so-called {{w|Zodiac Killer}}, a serial killer who was active in California in the 1960s and 1970s. The letters are [http://en.wikisource.org/wiki/Zodiac_Killer_letters available at Wikisource.] Some of the letters are encoded, only some of which have been deciphered. The killings remain unsolved.
|-
|Dyatlov Pass incident
|93%
|96% 
|On 2 February 1959, nine skiers in the northern Ural Mountains apparently {{w|Dyatlov Pass Incident|fled their tents without taking time to put on winter clothing}}. They were found dead, some with physical injuries. There are in fact a number of theories regarding this event, and it is not clear which one Randall regards as being obviously correct.
|-
|Kentucky meat shower
|85%
|93% 
|In 1876, a number of chunks of meat {{w|Kentucky meat shower|fell from the sky}} in Kentucky; this was possibly [http://blogs.scientificamerican.com/running-ponies/2014/12/01/the-great-kentucky-meat-shower-mystery-unwound-by-projectile-vulture-vomit/ projectile vomit from vultures.]
|-
|Lindbergh baby
|17%
|25% 
|The {{w|Lindbergh kidnapping}} was the kidnapping and murder of 20-month old Charles Lindbergh Jr. in 1932. Various {{w|Lindbergh kidnapping#Controversy|conspiracy theories}} surround the event.
|-
|Lost colony
|74%
|83% 
|The {{w|Roanoke Colony}} was the first English attempt to establish a permanent settlement in the New World. The colony of over a hundred settlers disappeared some time in the late 1580s, with no signs of violence and no definitive evidence as to what happened. However, given the hardships faced by the colonists when they were left and that the buildings in the colony were dismantled, indicating departure was not hurried, it is likely they moved and/or integrated with the local tribes. Which probably accounts for Randall's high "explainable" rating. (See title text of [[950: Mystery Solved]])
|-
|Toynbee tiles
|25%
|34% 
|{{w|Toynbee tiles}} are colorful ceramic tiles with cryptic messages that have been found embedded in asphalt in the streets of various midwestern-to-eastern cities in the United States and four South American cities.
|-
|Amelia Earhart
|56%
|74% 
|{{w|Amelia Earhart}} and her navigator tried to circumnavigate the earth along the equator in a small airplane in 1937, but {{w|Amelia Earhart#Speculation on disappearance|disappeared}} over the Pacific Ocean without any trace. See also [[950: Mystery Solved]].
|-
|Jimmy Hoffa
|10%
|42% 
|{{w|Jimmy Hoffa}} was an American labor union leader who disappeared in 1975. He is widely believed to have been murdered. (See title text of [[950: Mystery Solved]])
|-
|Voynich manuscript
|35%
|68% 
|The {{w|Voynich manuscript}} is an illustrated codex hand-written in an unknown writing system. It came to public attention in the early 20th century and probably was written in Italy in the early 15th century. See also [[593: Voynich Manuscript]].
|-
|Loch Ness monster
|64%
|100% 
|The {{w|Loch Ness Monster}} is a supposed animal that reputedly inhabits Loch Ness, a lake in Scotland. Multiple complete scans of the lake using sonar show no evidence of the monster, and the lake ecosystem is far too small to support even a single creature as large as the monster is alleged to be.
|-
|Bigfoot
|60%
|98% 
|{{w|Bigfoot}} is a supposed animal or hominid that reputedly inhabits the Pacific Northwest region of North America.
|-
|JFK
|38%
|86% 
|The 1963 {{w|Assassination of John F. Kennedy|assassination of President John F. Kennedy}} has inspired many conspiracy theories, beginning almost immediately after the event. The subsequent murder of assassin Lee Harvey Oswald added fuel to the fire by encouraging speculation that he was silenced to cover up the true story. It seems Randall thinks this has been explained pretty well.
|-
|Oak Island money pit
|32%
|98% 
|An indentation in the ground on {{w|Oak Island}} (off the east coast of Nova Scotia, Canada), led to over 200 years of treasure hunting, with the excavations repeatedly hampered by flooding pit collapses. A few flagstones, and periodic layers of logs are all that have been found. Rumours abound as to what it conceals: Marie Antoinnette's jewels, pirate treasure and Shakespeare's manuscripts have all been suggested. It is called The Money Pit, because of all the money that has been wasted in trying to solve the mystery.
|-
|Why I keep putting ice cream back in the fridge instead of the freezer
|0%
|96% 
|Apparently, Randall absent-mindedly puts his ice cream container into the refrigerator rather than into the freezer.
|}

Note that Randall used a similar diagram in [[1242: Scary Names]].

==Transcript==
:[In a frame at the top left of the panel:]
:'''Mysteries'''

:[A chart with two crossing lines with double arrows. Each arrow is labeled:]
:X-axis left: Not that weird
:X-axis right: Weird as Hell
:Y-axis top: I have no explanation
:Y-axis bottom: Explanation seems pretty clear

:[In the chart there are 22 bullets. Each bullet is labeled. Below the labels are given from top to bottom in each of the four quadrants of the chart:]

:[Top left quadrant:]
:Who Carly Simon is singing about in You're So Vain
:UVB-76
:Lindbergh baby
:Toynbee tiles
:Jimmy Hoffa

:[Top right quadrant:]
:MH370
:Lead Masks Case
:DB Cooper
:The Wow signal
:Salish Sea feet
:Mary Celeste

:[Bottom left quadrant:]
:Voynich manuscript
:JFK
:Why I keep putting ice cream back in the fridge instead of the freezer
:Oak Island Money Pit

:[Bottom right quadrant:]
:Zodiac letters
:Amelia Earhart
:Lost Colony
:Kentucky meat shower
:Bigfoot
:Loch Ness Monster
:Dyatlov Pass incident

{{comic discussion}}
[[Category:Charts]]
[[Category:Wikipedia]]

Talk:202: YouTube

2015-07-19T20:44:28Z

HiddenWindshield:

In the transcript, it says simpleplan2009's comment was posted 3 minutes ago. However, in the image, it clearly says 5 minutes. [[User:Caagr98|Caagr98]] ([[User talk:Caagr98|talk]]) 19:01, 17 April 2013 (UTC)
:I agree. In theory a 3 and a 5 could be hand-written to be hard to differentiate, but here it is clear. Changed. (And added the first line.) [[User:Markhurd|Mark Hurd]] ([[User talk:Markhurd|talk]]) 10:56, 19 April 2013 (UTC)
::Changed it back, as the actual transcript on the comic page (as seen in the webpage source, and upon which the comic searches are based) says "3". I've added the reasoning in the explanation. [[User:NixillUmbreon|NixillUmbreon]] ([[User talk:NixillUmbreon|talk]]) 15:31, 20 January 2014 (UTC)
:::The image is the first source for the transcript here. Randall's transcript simply doesn't match the image.--[[User:Dgbrt|Dgbrt]] ([[User talk:Dgbrt|talk]]) 22:11, 20 January 2014 (UTC)

On Gunpistolman's comment, is [http://www.phys.ufl.edu/~det/phy2060/heavyboots.html the heavy boots story] worth a mention? [[User:B jonas|B jonas]] ([[User talk:B jonas|talk]]) 16:31, 1 November 2013 (UTC)
:Not needing a mention in the explanation, but thank you for the link. Richard Feynman would be glowing in his grave at the state of science education in this country. {{unsigned ip|108.162.219.223}}

The British sketch comedy TV show ''That Mitchell and Webb Look'' has an excellent [https://www.youtube.com/watch?v=P6MOnehCOUw Moon Landing Sketch] with similar humor to this joke. [[User:Beolach|Beolach]] ([[User talk:Beolach|talk]]) 22:18, 31 March 2014 (UTC)

I think that it's possible the video is the Astronaut music video by Simple Plan. Led to believe it by the username simpleplan2009 {{unsigned ip|108.162.216.124}}

American sheep are very offended by this. if sheep could read. --[[User:Dalonacueball|Dalonacueball]] ([[User talk:Dalonacueball|talk]]) 17:27, 24 March 2015 (UTC)

All of the comments in the comic are actual YouTube comments, taken from the video https://www.youtube.com/watch?v=Vml7pZJujF0 (although the usernames were changed, presumably to protect the stupid). Should that be mentioned in the description? [[User:HiddenWindshield|HiddenWindshield]] ([[User talk:HiddenWindshield|talk]]) 20:44, 19 July 2015 (UTC)