explain xkcd - User contributions [en]

2957: A Crossword Puzzle

2024-07-10T21:18:08Z

Twinnol: /* Explanation */

{{comic
| number = 2957
| date = July 10, 2024
| title = A Crossword Puzzle
| image = a_crossword_puzzle_2x.png
| imagesize = 740x937px
| noexpand = true
| titletext = Hint: If you ever encounter this puzzle in a crossword app, just [term for someone with a competitive and high-achieving personality].
}}

==Explanation==
{{incomplete|CreAAAAAAAAAted by AAAAAAAAAAA BOT - Please change this comment when editing this page. Do NOT delete this tag too soon.}}

* 1 across. Famous pvt. wilhelm quote: Reference to the {{w|Wilhelm scream}}.
* 11 across. An IPv4 record is an "A" record, an IPv6 record is four times the length and is designated an "AAAA" record.
* 15 across. A [https://en.wikipedia.org/wiki/Vigenère_cipher "Vignère Cipher"] translates the original text by the distance from A from the key, letter by letter. For instance, if the plaintext is "XK" and the key is "CD", the C shifts X 2 forward to become Z, and the D shifts K 3 forward to become N, yielding a ciphertext of "ZN". Since the ciphertext and the key are the same in this case, decryption just shifts all the letters back to A, akin to subtracting a number from itself and getting 0.
* 17 across. The {{w|A-10 Warthog}} is a well-known attack aircraft. Here, A-10 has been turned into AAAAAAAAAA (ten As).
* 18 across. Aphantasia is the inability to visualize. Following the instruction, we determine that '''A'''ph'''a'''nt'''a'''si'''a''' gives us the word "aaaa".
* 21 across. {{w|A4 paper}} (here written as AAAA) is the default size in Europe. It is approximately 0.24" narrower and 0.71" longer than the 8.5"x11" paper used in the United States, and due to having an aspect ratio of 1:sqrt(2), can be cut in half to create two half-sized sheets with exactly the same aspect ratio.
* 22 across. Unary's when you get to use just the one symbol. E.g. 32 in unary would be 11111111111111111111111111111111. The first four strings in unary, if you used A as the first (and only) symbol, would be A, AA, AAA, AAAA.
* 23 across. {{w|Lysene}} is an amino acid, with codons AAA and AAG (presumably the former is meant here).
* 29 across. A reference to Howard Dean, an American Democrat who ran for the party's nomination in 2004. He famously [https://www.youtube.com/watch?v=l6i-gYRAwM0 yelled at a rally] in a way that was thought to be bizarre and which, it is thought, doomed his campaign.
* 36 across. I.e. "open up". Or an expression of pain; particularly the only kind you can make with dental tools in your mouth. (As Autechre put it: [https://youtu.be/UppsLKz1iD4 "Now, I don't want you to panic... just lean back and relax."])
* 38 across. AAA the IATA code for the airport
* 41 across. Macaulay Culkin's review of aftershave: Famously in the movie {{w|Home Alone}} he puts it on because he's home all alone and dislikes it, emitting a scream, which could be transcribed like A's.
* 50 across. The call which Elsa hears in Frozen 2 is a sequence of four notes which resemble the Dies Irae. The sequence is sung entirely with an open rounded vowel sound, or a soft "a" sound.
* 1 down. {{w|AaAaAA!!! – A Reckless Disregard for Gravity}} - notably the title is commonly extended in promotional material beyond 6 A's.
* 2 down. 10101010 10101010 10101010 in binary is equivalent to "AAAAAA" in hexadecimal.
* 3 down. the Pixel 6a was released in July 22. Stylized in this puzzle as "AAAAAA"
* 5 down. The decimal number 43690 converted to hexadecimal is AAAA
* 26 down. A high budget video game is usually referred to as A Triple-A game, or AAA
* 29 down. `echo -n AAAAAAAA | sha256sum` outputs `c34ab6abb7b2bb595bc25c3b388c872fd1d575819a8f55cc689510285e212385`.
* 34 down. 440Hz is an "A" note. 7 pulses would be AAAAAAA
* 38 down. Eggs can be [https://www.saudereggs.com/blog/egg-grading-system/ "graded on a veriety if aspects"], with grades B, A, or AA. Eggs with a reasonably firm yolk are graded A, so having halve a dozen of them gives you AAAAAA eggs.
* 39 down. A [https://en.wikipedia.org/wiki/Multi-tap "multitap keyboard"] is a text entry system for mobile phones. Most numbers are associated with three letters, and tapping the same number multiple times in rapid succession selects the 1st, 2nd, or 3rd number. 2 is "a", 22 is "b", 222 is "c", 3 is "d", etc. 2-2-2-2-2-2 translates to "aaaaaa"
* 40 down. .- is Morse Code for A. It reads out as AAAAAA
* Hint: If you ever encounter this puzzle in a crossword app, just [ Type A ]

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

[A crossword puzzle image, with the following clues:]

:Across
:1. Famous Pvt. Wilhelm quote
:11. IPv6 address record
:15. "CIPHERTEXT" decrypted with Vigenere key "CIPHERTEXT"
:16. 8mm diameter battery
:17. "Warthog" attack aircraft
:18. Every third letter in the word for "inability to visualize"
:19. An acrostic hidden on the first page of the dictionary
:21. Default paper size in Europe
:22. First four unary strings
:23. Lysine codon
:24. 40 CFR part 63 subpart concerning asphalt pollution
:25. Top bond credit rating
:26. Audi coupe
:27. A pair of small remote batteries, when inserted
:29. Unofficial Howard Dean slogan
:32. A 4.0 report card
:33. The "Harlem Globetrotters of baseball" (vowels only)
:32. 2018 Kiefer song
:35. Top Minor League tier
:35. Reply elicited by a dentist
:38. ANAA's airport
:41. Macaulay Culkin's review of aftershave
:43. Marketing agency trade grp.
:44. Soaring climax of Linda Elder's ''Man of La Mancha''
:46. Military flight commuinity org.
:47. Iconic line from Tarzan
:48. Every other letter of Jimmy Wales's birth state
:49. Warthog'd postscript after "They call me ''mister'' pig!"
:50. Message to Elsa in ''Frozen 2''
:51. Lola, when betting it all on Black 20 in ''Run Lola Run''
:Down
:1. Game featuring "a reckless disregard for gravity"
:2. 101010101010101010101010 base 2-> base 16
:3. Google phone released July '22
:4. It's five times better than that ''other'' steak sauce
:5. ToHex(43690)
:6. Freddie Mercury lyric from ''Under Pressure''
:7. Full-size Audi luxury sedan
:8. Fast path through a multiple choice marketing survey
:9. 12356631 in base 26
:10. Viral Jimmy Barnes chorus
:11. Ruby Rhod catchphrase
:12. badbeef + 9efcebbb
:13. In Wet Let's ''Ur Mum'', what the singer has been practicing
:14. Refrain from Nora Reed bot
:20. Mario button presses to ascend Minas Tirith's walls
:24. Vermont historic route north from Bennington
:26. High-budget video game
:28. Unotrhodox Tic-Tac-Toe win
:29. String whose SHA-256 hash ends "...689510285e212385"
:30. Arnold's remark to the Predator
:31. The vowels in the fire salamander's binomial name
:32. Janet Leigh ''Psycho'' line
:34. Seven 440Hz pulses
:37. Audi luxury sports sedan
:38. A half-dozen eggs with reasonably firm yolks
:39. 2-2-2-2-2-2 on a multitap phone keypad
:40. .- .- .- .- .- .-
:42. Rating for China's best tourist attractions
:43. Standard drumstick size
:45. "The rain/in Spain/falls main-/ly on the plain" rhyme scheme

{{comic discussion}}

2594: Consensus Time

2022-03-18T14:09:50Z

Twinnol: /* Explanation */

{{comic
| number = 2594
| date = March 16, 2022
| title = Consensus Time
| image = consensus_time.png
| titletext = Now, you may argue that the varying hour lengths and feedback effects would cause chaos. To which I say, yeah, and I'm also curious to see how the weekday cycle interacts with it! So, you in?
}}

==Explanation==
{{w|Daylight Saving Time}}, a [[:Category:Daylight saving time|recurring theme]] on xkcd, has recently started (in the US, as of this comic's publication). At the time of transition, clocks in (most of) North America are turned an hour forward. People frequently complain about the switch into (and out of) DST, due to it having been invented for the no-longer-relevant cause of saving coal during wartime. One of many complaints is that it will still "feel" like 5 am at 6, or whatever other case. A few days before this comic went up, the United States Senate passed the {{w|Sunshine Protection Act}}, which would permanently abolish the biannual daylight savings adjustment, setting (what was) the local daylight savings time offset as the year-round time zone for all but a handful of states and territories rather than eliminating DST completely.
[[Randall]], jumping on this topic, proposes a system that allows everybody to say when it "feels" like 9 am, and then the median 9 am will become the real 9 am. This happens every day. As the title text points out, this would be chaotic and, to put it bluntly, awful.{{citation needed}}

Presumably the times indicated on this diagram are as the clocks in this time zone would indicate, as opposed to an "ordinary" reference time.

Although the hours between midnight and 9 am are labelled as "longer" (which we can assume means each would take longer than an hour of ordinary time to pass) the effect on the remaining hours is left unstated. If we assume that the remaining hours pass at the usual rate then this would suggest that midnight would come sooner or later than normal and hence the next vote would occur sooner or later respectively. This implies the time in this time zone could drift further than a day (or even multiple days) from existing time-zones which could be what is meant by "feedback", "chaos" and the effect on weekdays mentioned in the title text.

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

:Proposal: Consensus Time

:Every day, anyone in the time zone can press a button when they feel like it's 9 AM. The next day, clocks slow down or speed up to match the median choice from the previous day.

:[A diagram representing the hours of two days with tick marks, with some of the tick marks longer than others and/or in boldface, and some of them labeled as follows:]

:Midnight
:6AM
:9AM today
:Median
:Noon
:6PM
:Midnight
:6AM
:9AM tomorrow
:Noon
:6PM
:Midnight

:[A brace connects the period from the second "Midnight" to "9AM tomorrow". It is labeled:]
:Longer hours

:[A scatterplot of 57 dots appears below the hashmarks, indicating the distribution of when participants pushed the "9 AM" button. The most extreme outliers are at roughly 3AM and 9PM, but they most densely cluster around a vertical dotted line labelled "Median" at approximately 11:15AM, interrupted as it passes through the main mass of dots at roughly the position of the 29th plotted dot from either end.]

:[Megan, facing to the left, and Cueball, facing to the right, each hold a handheld device. The devices are too small to see clearly but are making sounds, implying that each of them has just pressed the "9 AM" button.]
:Beep
:Beep

{{comic discussion}}

[[Category:Daylight saving time]]
[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Megan]]

2379: Probability Comparisons

2020-10-31T16:36:12Z

Twinnol: /* Explanation */

{{comic
| number = 2379
| date = October 30, 2020
| title = Probability Comparisons
| image = probability comparisons new.png
| titletext = Call me, MAYBE.
}}

==Explanation==
{{incomplete|Created by LEBRON JAMES THROWING M&Ms AT A KEYBOARD. The table for the explanations of the chances isn't complete, and nor is the transcript. Do NOT delete this tag too soon.}}

This is a list of probabilities for different events. There are numerous recurring themes, of which the most common are free throws (13 entries), birthdays (12), dice (12, split about evenly between d6 and d20 types), M&M candies (11), playing cards (9), NBA basketball mid-game victory predictions (9), Scrabble tiles (7), coins (7), white Christmases (7), and the NBA players Stephen Curry and LeBron James (7 each).

Themes are variously repeated and combined, for humorous effect. For instance, there are entries for both the probability that St. Louis will have a white Christmas (21%) and that it will not (79%). Also given is the 40% probability that a random Scrabble tile will contain a letter from the name "Steph Curry".

There are 80 items in the list, the last two of which devolve into absurdity - perhaps from the stress of preparing the other 78 entries.

The probabilities are calculated from [https://xkcd.com/2379/sources/ these sources], as mentioned in the bottom left corner.

{| class="wikitable sortable"
! Odds
! Text
! Explanation
|-
| 0.01%
| You guess the last four digits of someone's {{w|Social Security Number}} on the first try
| There are 10 digits in a Social Security Number. (1/10)4 = 0.0001, or 0.01%
|-
| 0.1%
| Three randomly chosen people are all left-handed
| The chances of being left handed is about 10%, and 10%3 = 0.1%.
|-
| rowspan="2" | 0.2%
| You draw 2 random {{w|Scrabble}} tiles and get M and M
|
|-
| You draw 3 random {{w|M&Ms}} and they're all red
| There are 3 red, 5 green, and 8 blue M&Ms. 3/16 × 2/15 × 1/14 ≈ 0.17%
|-
| 0.3%
| You guess someone's birthday in one try.
| 1/365 ≈ 0.27%.
|-
| rowspan="2" | 0.5%
| An {{w|NBA}} team down by 30 at halftime wins
|
|-
| You get 4 M&Ms and they're all brown or yellow
|
|-
| rowspan="2" | 1%
| {{w|Steph Curry}} gets two free throws and misses both
|
|-
|{{w|LeBron James}} guesses your birthday, if each guess costs one free throw and he loses if he misses
|
|-
| rowspan="2" | 1.5%
| You get two M&Ms and they're both red
|
|-
| You share a birthday with a {{w|Backstreet Boys|Backstreet Boy}}
|
|-
| 2%
| You guess someone's card on the first try
| There are 52 cards in a normal deck of cards (excluding jokers), which is approximately 0.019 (2%).
|-
| rowspan="2"| 3%
| You guess 5 coin tosses and get them all right
|
|-
| Steph Curry wins that birthday free throw game
|
|-
| rowspan="3"| 4%
| You sweep a 3-game {{w|rock paper scissors}} series

|
|-
| {{w|Portland, Oregon}} has a {{w|White Christmas (weather)|white Christmas}}
|
|-
| You share a birthday with two {{w|US Senator}}s
|
|-
| rowspan="2"| 5%
| An NBA team down 20 at halftime wins
|
|-
| You roll a natural 20
There are twenty sides to a d20; 1/20 = 0.5 = 5%
|
|-
| 6%
| You correctly guess someone's card given 3 tries
| Assuming you guess three different cards, 3/52 = 0.05769 ~ 6%
|
|-
| 7%
| LeBron James gets two free throws and misses both
|
|-
| 8%
| You correctly guess someone's card given 4 tries
| Assuming you guess four different cards, 4/52 = 0.0769 ~ 8%
|
|-
| 9%
| Steph Curry misses a free throw
|
|-
| rowspan="2"|10%
| You draw 5 cards and get the Ace of Spades
| There are 52 cards in a normal deck of cards (excluding jokers), and the Ace of Spades is one of them. The chances of getting the card is 1 - 51/52 * 50/51 * 49/50 * 48/49 * 47/48 which is approximately 0.09 (9%), which roughly checks out. 
|-
| There's a {{w|Moment magnitude scale|magnitude}} 8+ earthquake in the next month
|
|-
| 11%
| You sweep a 2-game rock paper scissors series
| You have a 1/3 chance of winning the first comparison, and a 1/3 chance of winning the second. (1/3) * (1/3) = 1/9 ~ 0.11 = 11%
|
|-
| rowspan="3"|12%
| A randomly-chosen American lives in {{w|California}}
|
|-
| You correctly guess someone's card given 6 tries
|
|-
| You share a birthday with a {{w|US President}}
|
|-
| rowspan="3"|13%
| A {{w|Dice#Polyhedral_dice|d6}} beats a {{w|Dice#Polyhedral_dice|d20}}
|
|-
| An NBA team down 10 going into the 4th quarter wins
|
|-
| You pull one M&M from a bag and it's red

|-
| 66%
| A randomly chosen movie from the main Lord of the Rings trilogy has “of the” in the title twice
| The titles are:
* ''The Lord '''of the''' Rings: The Fellowship '''of the''' Ring''
* ''The Lord '''of the''' Rings: The Two Towers''
* ''The Lord '''of the''' Rings: The Return '''of the''' King''
All of them have “of the” at least once, in “The Lord of the Rings”, but only the first and third have it twice, and 2/3 ≈ 66%.

|-
| 90%
| Someone fails to guess your card given 5 tries
| Assuming they guess five different cards, there are 47 unguessed cards left. 47/52 = 0.90385 ~ 90%
|
|-
| rowspan="2"| 91%
| You incorrectly guess that someone was born in August
|
|-
| Steph Curry makes a free throw
|
|-
| 92%
| You guess someone's birth month at random and are wrong
|
|-
| 93%
| Lebron James makes a free throw given two tries
|
|-
| 94%
| Someone fails to guess your card given 3 tries
|
|-
| 95%
| An NBA team wins when they're up 20 at halftime
|
|-
| 96%
| Someone fails to guess your card given 2 tries
|
|-
| 97%
| You try to guess 5 coin tosses and fail
|
|-
| 98%
| You incorrectly guess someone's birthday is this week
|
|-
| 98.5%
| An NBA team up 15 points with 8 minutes left wins
|
|-
| 99%
| Steph Curry makes a free throw given two tries
|
|-
| 99.5%
| An NBA team that's up by 30 points at halftime wins
|
|-
| 99.7%
| You guess someone's birthday at random and are wrong
|
|-
| 99.8%
| There's not a {{w|Moment magnitude scale|magnitude}} 8 quake in {{w|California}} next year
|
|-
| 99.9%
| A random group of three people contains a right-hander
|
|-
| 99.99%
| You incorrectly guess the last four digits of someone's social security number
|
|-
| 99.9999999999999995%
| You pick up a phone, dial a random 10-digit number, and say 'Hello Barack Obama, there's just been a {{w|Moment magnitude scale|magnitude}} 8 earthquake in {{w|California}}!" and are wrong
|
|-
| 0.00000001%
| You add "Hang on, this is big — I'm going to loop in Carly Rae Jepsen", dial another random 10-digit number, and she picks up
|
|}

The title text refers to the song {{w|Call Me Maybe}} by Carly Rae Jepsen (cited twice in the list). "MAYBE" is emphasized perhaps because the probability of getting her phone number correct, as in the last item in the list, is very low. The capitalization could also be a reference to Scrabble tiles as was previously mentioned in association with Carly Rae Jepsen.

==Trivia==
In the original comic, "outside" in the 88% probability section is spelled incorrectly as "outide". In addition, the 39% section had "two free throw" instead of "throws".

Pace previous comment, the 67% probability of rolling at least a 3 with a D6 is correct. "At least a 3" means a 3, 4, 5, or 6.

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

'''PROBABILITY COMPARISONS'''

{{comic discussion}}
[[Category:Statistics]]
[[Category:Comics featuring real people]]

2367: Masks

2020-10-02T19:16:42Z

Twinnol:

{{comic
| number = 2367
| date = October 2, 2020
| title = Masks
| image = masks.png
| titletext = Haunted Halloween masks from a mysterious costume shop that turn you evil and grow into your skin score a surprisingly high 80% filtration efficiency in R. L. Stine-sponsored NIOSH tests.
}}

==Explanation==
{{incomplete|Created by a BATMAN WEARING A N95 MASK. Please mention here why this explanation isn't complete. Do NOT delete this tag too soon.}}

This comic is a line from top to bottom explaining how good different types of masks are at preventing respiratory virus transmission. As with many comics in 2020, it was made with Coronavirus strain 2019 (COVID-19) in mind, a virus that primarily transmits through air droplets expelled from the human nose and mouth.

*'''Lone Ranger''' and '''Zorro''': A strip of cloth around the eye-level. Does not cover the mouth and nose, the main ways the virus enters the body.
*'''{{w|Batman}}''': A helmet and visor. Does not cover the mouth, but may cover the nose.
*'''Theater masks''': A pair of {{w|Sock and buskin}} masks, traditionally used as a symbol of performance theater since ancient Greece. The eye and mouth holes are often open, thus exposing the wearer.
*'''Skincare''': A layer of moisturizer. By nature, it does not cover the mouth or nostrils, but it is usually worn by someone sitting in a chair or lying back on a bed, not out getting in other people's personal space.
*'''Scarecrow''': A burlap sack. While it provides some cover to the mouth and nose, it is heavily porous.
*'''Guy Fawkes''': A plastic mask. Most Guy Fawkes masks provide small holes in the front for comfort, thus facilitating spread of the virus.
*'''Cloth''': A cloth mask that blocks most large particles, like virus-laden saliva. To be most effective, it must cover nose as well as the mouth. These are much cheaper than N95 masks, and can be reused by washing.
*'''{{w|Spiderman}}''': A full face covering of spandex-like material. Would block most virus particles.
*'''{{w|N95 mask}}''': A surgical mask. The name "N95" signals that it is not resistant to oil, but successfully filters 95% of airborne particles. It has proven to be one of the more successful masks during the 2020 pandemic.
*'''{{w|Scuba_Diving|SCUBA}}''': A '''S'''elf-'''C'''ontained '''U'''nderwater '''B'''reathing '''A'''pparatus. Most SCUBA equipment used an open-circuit design allowing exhaled air to vent to the atmosphere. Underwater, this would not be a threat to other divers who would also be breathing air from their tanks. However, on land this a typical SCUBA regulator would expose others to virus particles. Closed-circuit SCUBA apparatus recirculate the user’s gas supply but they still contain a means of venting extra gas into the atmosphere. Neither system contains expiratory HEPA filters making both ineffective at preventing virus transmission.
*'''Vader''': A suit of armor with a built-in rebreather. Similar to SCUBA gear, circulates air back to the user, preventing spread of the virus to anyone else.
*'''Mysterio''': A glass helmet. In the comics Mysterio often uses mind-altering chemicals, and his suit is designed to shield himself from his own weapons. By the same design, it would shield himself and others from the spread of viral infection.
*'''Haunted Halloween Masks''': A reference to {{w|The Haunted Mask}} by {{w|R. L. Stine}}. The mask transforms the wearer into a monster, with an open (uncovered) nose and mouth, but apparently R. L. Stine had them tested and found that the wearer is still somehow substantially protected against infection (in spite of the other negative side effects of being cursed).

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

[Title at top]
:'''Masks'''
:By effectiveness at preventing respiratory virus transmission

[Vertical Line going top to bottom. At the top: Not effective. In the middle: Effective. On the bottom. Extremely Effective. From top to bottom:]

:[Approx. 2%]Zorro/Lone Ranger
:[Approx. 3%]Batman
:[Approx. 7%]Theater
:[Approx. 10%]Skincare
:[Approx. 15%]Scarecrow
:[Approx. 18%]Guy Fawkes
:[Approx. 48%]Cloth
:[Approx. 52&]Spiderman
:[Approx. 68%]N95
:[Approx. 71%]Scuba
:[Approx. 80%]Vader
:[Approx. 90%]Mysterio



{{comic discussion}}

2253: Star Wars Voyager 1

2020-01-11T22:35:25Z

Twinnol: /* Explanation */

{{comic
| number = 2253
| date = January 10, 2020
| title = Star Wars Voyager 1
| image = star_wars_voyager_1.png
| titletext = There's some flexibility depending on your standards for measuring runtime and the various special editions. If you still want to have a party, I'm sure you can find some combination that works.
}}

==Explanation==
{{incomplete|Created by a BERT. This explanation is basic, and needs more information. DO NOT delete this tag too soon.}}

[[Cueball]] has added together all the runtimes of the {{w|Star Wars}} movies (episodes I-IX) and then calculated the exact time at which a message sent to {{w|Voyager 1}} will have that exact duration in {{w|light speed}} delay. He announces this information to [[Megan]] and [[Beret Guy]] only seconds before it occurs, allowing him to signal the moment by saying "Now!"

Megan expresses surprise that the event isn't being celebrated with fireworks. Judging by the fact that she doesn't look up from her book, her surprise is insincere. Beret Guy breaks into song with the New Year's traditional "{{w|Auld Lang Syne}}".

This comic highlights a coincidental relationship between the Star Wars Episodes and the {{w|NASA}} Space Probe "Voyager 1", which most likely no one else has thought about, but most likely fitting well with fans of both xkcd and Star Wars.

The {{w|Star Wars (film)|first Star Wars episode}} was released on 25th May 1977 only four months before Voyager 1 was launched on 5th September 1977. The {{w|Star Wars: The Rise of Skywalker|last episode}} was released more than 42.5 years later on 20th December 2019 only three weeks before this comic.

Voyager 1 was, with a distance of 148.68 {{w|Astronomical unit}}s (22.2 billion km; 13.8 billion mi) from Earth as of December 26, 2019, the most distant human-made object from Earth. This data is given with reference in the Wikipedia article for Voyager 1. That was less than a week after the release of the new movie. That is [https://www.wolframalpha.com/input/?i=148.68+AU+in+light+hours approximately 20.6 light hours] away. With the recently released last episode the total viewing time of the nine episodes is [[#Table of runtime| 20.35 hours]] (not including the two spin-off movies {{w|Rogue One}} and {{w|Solo: A Star Wars Story|Solo}}). So a discrepancy of 15 minutes. This could be explained by the title text.

In the [https://voyager.jpl.nasa.gov/mission/status/ mission status] of the two Voyager probes there were a [https://www.explainxkcd.com/wiki/images/1/1c/Voyager_mission_status_2020-01-10.png One-Way Light Time] of 20 hours 36 minutes and 46 seconds on the day the comic was released. This corresponds to 20.613 light hours, only the 46 seconds deviation from exactly 20.6 hours.

This is an odd coincidence that Cueball/[[Randall]] saw significant enough to mark with a timer and acknowledgement to Megan and Beret Guy (and the rest of the fans of xkcd).

In the title text Randall notes that there can be different ways of measuring run times, both if you do not count credits into the runtime or with more than one version existing of at least the original trilogies films, with added extra footage. This means that if you choose the longest possible run time, you may still have a chance to throw a party for some time to come, as every extra minute of film will add time before Voyager 1 reaches that extra light minute.

However as demonstrated in the [[#Table of runtime|Table of runtime]] below, then only for the very longest versions would this have worked around the time of release of the movie. Now three weeks later it is too late, until a possible future Episode X would be released.

When Voyager 1 {{w|Voyager_1#Exit_from_the_heliosphere|left the heliosphere}} it was traveling at about 17 kilometers per second (11 mi/s), making it the fastest heliocentric recession speed of any spacecraft, and it is not really slowing down. (Do note that the speed with which it travels from Earth is not the same since Earth is in orbit around the Sun and sometimes travels faster towards Voyager 1 than Voyager 1 leaves the sun, but then Earth turns and goes the other way!)

Since a light minute is [https://www.wolframalpha.com/input/?i=1.799%C3%9710%5E7+kilometers&assumption=%22ClashPrefs%22+-%3E+%22%22 1.799×107 kilometers] it takes Voyager 1 [https://www.wolframalpha.com/input/?i=1+light+minute%2F17+kilometers+per+second+in+days 12.25 days] to travel this far. So for every minute added to the run time, the party start time will be delayed by more than 12 days. However it is already 14 days since the distance given on Wikipedia, so more than one extra minute is needed to postpone the party to after the release day of the comic.

Last possible chance is to assume that all run times have been rounded down, which could add anywhere from 9 half to almost 9 full minutes, if they round 125.9 down to 125, and not only rounded 125.4 (and not rounding 125.5 up). Actually assuming all runtimes are rounded down it is realistic that there is on average half a minute extra runtime per episodes for 4.5 minutes extra time. This would buy 55 extra days from the 26th of December... But to find this out correctly, someone would need to review all the 9 episodes from the very first second to the very last of the most extended versions. It seems that it could still be possible to find a day where the party can still be held after the release day of the comic.

In the extreme case that all movies went 59 seconds over a full minute, but all times are rounded down, it would add 8 minutes and 51 seconds. This could give 108 extra days from 2019-12-26, meaning that [https://www.wolframalpha.com/input/?i=2019-12-26%2B108days Easter Sunday 2020] (2020-04-12) would be the last possible day for such a party.

==Table of runtime==
*Here is a table with the nine episodes (ordered in release order, but it is sortable and the episode number is also included)
*The title, the run time and the release day (theatrical release in the US) is {{w|Star_Wars#Film|taken from Wikipedia}}.
*The total run time in hours are summed up chronological in the last column. (So no meaning if the table is sorted).
*From this the total runtime comes up to 1221 minutes which is only 20.35 hours 15 minutes shorter than the time it currently takes light to travel to Voyager 1.
**Seems like Randall used a different version of the runtime than standard per wikipedia.
**To investigate this the longest time of any version as given on {{w|IMDb}} (or Wikipedia, which was longer than on IMDb with 1 minute for Epiosde 8) was added in the next column with the total time for these longest versions in the last. This brings the total time up to 1236 exactly 15 minutes extra getting a total of 20.6 hours.
**So at the distance given on Wikipedia December 26th, it must have been very close to the ''Now'' Cueball mentions. But now a few weeks later the discrepancy is even larger, and there seems to be no way to choose an even longer running time than those given below. So only rounding down could save the chance to postpone the party for a later day.
{|class="wikitable sortable"
!#
!Title
!Release day
!Run time (min)
!Total time (hour)
!Longest run (min)
!Sum longest (hour)
|-
| 4 ||{{w|Star Wars (film)| Star Wars}}||1977-05-25||121||2.02|| 125 || 2.08
|-
| 5 ||{{w|The Empire Strikes Back}}||1980-05-21||124||4.08 || 127 || 4.20
|-
| 6 ||{{w|Return of the Jedi}}||1983-05-25||132||6.28 || 134 || 6.43
|-
| 1 ||{{w|Star Wars: Episode I – The Phantom Menace}}||1999-05-19||133||8.50 || 136 || 8.70
|-
| 2 ||{{w|Star Wars: Episode II – Attack of the Clones}}||2002-05-16||142||10.87 || 142 || 11.06
|-
| 3 ||{{w|Star Wars: Episode III – Revenge of the Sith}}||2005-05-19||140||13.20 || 140 || 13.4
|-
| 7 ||{{w|Star Wars: The Force Awakens}}||2015-12-18||135||15.45 || 138 || 15.7
|-
| 8 ||{{w|Star Wars: The Last Jedi}}||2017-12-15||152||17.98 || 152 || 18.22
|-
| 9 ||{{w|Star Wars: The Rise of Skywalker}}||2019-12-20||142||20.35 || 142 || 20.58
|}

==Transcript==
:[Cueball is looking down at the smartphone he is holding in one hand, while he is holding his other hands finger up in the air. He is standing behind an armchair where Megan is sitting reading a book or paper. She holds it open with both hands. She has turned her head halfway towards him. In front of her sitting on the floor, is Beret Guy, legs bent and leaning back resting on one hand, with his phone in the other hand.]
:Cueball: The time it takes light to travel between Earth and '''''Voyager 1''''' is exactly equal to the combined runtime of '''''Star Wars''''' episodes I-IX...

:[A slim beat panel, showing only Cueball standing in the same pose as in the first panel.]

:[Cueball looks up from his phone and raises his finger higher up. Megan has turned back to reading. Beret Guy looks up, and he has put his phone on the floor to put his, now free, hand on his heart, while singing, as indicated both with nodes before and after the lyrics he sings as well as letting his speech line start at a starburst near his head, rather than just beginning near the head, as normally.]
:Cueball: ...'''''Now!'''''
:Megan: Weird that I don't hear any fireworks.
:Beret Guy (singing): '''Should ollld acquaintance be forgooot'''

{{comic discussion}}

[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Megan]]
[[Category:Comics featuring Beret Guy]]
[[Category:Star Wars]]
[[Category:Space probes]]
[[Category:Songs]]
[[Category:New Year]]

2101: Technical Analysis

2019-01-21T13:08:03Z

Twinnol: /* Explanation */

{{comic
| number = 2101
| date = January 21, 2019
| title = Technical Analysis
| image = technical_analysis.png
| titletext = "I [suspect] that we are throwing more and more of our resources, including the cream of our youth, into financial activities remote from the production of goods and services, into activities that generate high private rewards disproportionate to their social productivity. I suspect that the immense power of the computer is being harnessed to this 'paper economy', not to do the same transactions more economically but to balloon the quantity and variety of financial exchanges." --James Tobin, July 1984
}}

==Explanation==
{{incomplete| Comic is still undergoing TECHNICAL ANALYSIS (this is just the prologue). Do NOT delete this tag too soon.}}

Technical analysis is a field which attempts to study stocks, cryptocurrency, etc. statistically, seeking to profit off the patterns that are found there.

The theoretical value of a stock is the sum of all its future earnings, with earnings in the future discounted appropriately to account for the {{w|time value of money}}. Because these earnings are never fully predictable, traders may have different ideas about the true value of a stock, and buy the stock if they believe the currently offered prices are particularly low, or sell it when the prices are high.

Technical analysis, however, does not even attempt to understand the earnings of the stock, instead focusing on the shapes and patterns that result from traders making their moves. While there is a human behavioral component to stock trading, it is not clear that one can extract much information from the shapes of stock charts. To the extent it does work, a substantial part of its success may be simply an artifact of the herd behavior of traders who engage in technical analysis, a zero-sum game.

“…Just seeing patterns in a graph of a random walk” is likely a reference to the book ''A Random Walk Down Wall Street'' by Burton Malkiel, a popular investment book. One section of the book argues against the merits of technical analysis purporting that no one can predict the future.

The comic displays a stock price chart, annotated with labels which purport to be technical analysis. These labels are nonsense: "allegro" and "prologue" (musical terms such as may be used in the introduction of a performed piece), "lumbar support" (the thing in a chair shaped to better support your back), "bathtub" (possibly a reference to the so-called "{{w|Bathtub curve}}"). One label celebrates that "these two points define a line! Promising signal." (In Euclidian geometry, any two points define a line.)

The mouseover text is a quote from {{w|James Tobin}} (from his 1984 paper [https://economicsociologydotorg.files.wordpress.com/2014/12/tobin-on-the-efficiency-of-the-financial-system.pdf On the efficiency of the financial system]) that raises a question of very talented people building systems to make themselves a lot of money without actually accomplishing anything worth money. This concern is perhaps not in and of itself about technical analysis, but more about the stock market and related trading ecosystems in general, in particular high speed traders. While it is not always easy to understand why certain forms of market activity might be valuable, and hard to put a price tag on concepts like "risk," "liquidity" and "price discovery," sometimes people are just working to trick others into bad deals, or forcing market participants to pay them {{w|Rent-seeking|unearned money}}. This may make the smart people a lot of money, but it does so by harming society, not helping it.

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

{{comic discussion}}