explain xkcd - User contributions [en]

2892: Banana Prices

2024-02-14T04:56:22Z

172.71.178.22: /* Explanation */ Case-correction, initially, but that superceded by other editing nicities. Did the editor intend to add this to Talk? Added own further analysis.

{{comic
| number = 2892
| date = February 9, 2024
| title = Banana Prices
| image = banana_prices_2x.png
| imagesize = 564x378px
| noexpand = true
| titletext = It's a linear extrapolation, Michael. How big could the error be? 10%?
}}

==Explanation==
{{incomplete|Created by a MANDALORIAN BANANA GRABBER - Please change this comment when editing this page.}}

[https://www.youtube.com/watch?v=Nl_Qyk9DSUw ‘It’s one banana, Michael. What could it cost, $10?'] is a line from an {{w|Arrested Development}} episode (Season 1, Episode 6, "Charity Drive", 2003) that became a well-known meme used to mock out-of-touch elites. The character who spoke this line (Lucille Bluth, a wealthy socialite) made a satirically high estimate for the price of a banana because she had never bought her own groceries. The implication is that she sees $10 as a trivially small amount of money, and has trouble conceiving of anything that costs less. According to the graph, the banana price at the time of that episode was actually just under 25 cents, and the price at the time of this comic’s publication (2024) is around 30 cents.

However, the premise of the bananas Lucille was talking about were frozen and chocolate-dipped treats. Still, the average price for that type of banana would range between $1.25 and $3.50 in the early 2000s (depending on location, and whether it was served with additional toppings), which may be equivalent to $2.50 - $5.00 by 2023. By using the current highest value and the {{w|Rule of 72}}, this indicates that a general inflation rate of no more than 0.72% would give us the century of leeway, or 1.44% from the lower end (still well below the given historical rate that demonstrably applies across the past twenty years).

The comic is a wry observation that the irony of this sitcom line will "probably" be anachronistically meaningless in a century or so, presenting three predictions of banana prices over the next 250 years that each extrapolate from the current 2024 price using different long-term inflation rates.

The three extrapolations use (1) the general inflation rate (a value dominated by the cost of housing), (2) the inflation rate for fresh fruit, and (3) 45 years of historic banana prices. Those models present the joke becoming reality around 2140, 2170 and 2250, respectively.

The caption’s claim that banana prices could exceed $10 in a century are based on the fastest rising extrapolation, the one for “general inflation.” This extrapolation predicts a banana’s price to rise from 30 cents to $10 in approximately 115 years. This 115-year increase corresponds to an average long-term inflation rate of about 3.2%, close to the historic US average.

The reference to "BLS/St. Louis FRED" refers to The {{w|Bureau of Labor Statistics}} and {{w|St. Louis Fed Financial Stress Index|St Louis FRED}}, widely respected sources of economic data. The Federal Reserve Bank of St. Louis maintains the FRED database; FRED stands for Federal Reserve Economic Data.

The title text continues the ignorant tone of Lucille Bluth to make two jokes.
# A satirical guess of 10% error. The humor is that the three predictions themselves (from 115 years to 220 years) predict wildly different years of a $10 banana. Economic extrapolation into the distant future is at most an educated guess, with an expected error far in excess of 10%. Guessing such small errors in such speculative projections is just as clueless as guessing that individual bananas cost so much.
# An ignorant reference to these as “linear extrapolations.” While they look linear, they are actually ''exponential'' extrapolations. The graph is log-linear, with price as a logarithmic scale on the vertical (left) axis, which makes it possible to visualize the exponential growth extrapolation as a straight line. In other words, an extrapolation line on a graph with a logarithmic scale is actually exponential.

It’s not typical to plot commodity prices on a log-scale, but maybe Randall did this to allow himself to make this subtle “linear extrapolation” joke.

This comic uses several common xkcd themes:
* '''Log scales''' and their peculiarities are a recurring xkcd theme, and this is the second comic in a row to play with logarithms (the prior one being [[2891: Log Cabin]]).
* It's also the second comic in the last four to involve '''predictions across centuries''' (i.e. [[2889: Greenhouse Effect]]).
* Another '''extrapolation''' comic includes [[605: Extrapolating]]. And this comic looks a lot like [[1007: Sustainable]].

===Discussion of price references in fiction===
It's common for fictional works to avoid mentioning actual prices or amounts of money. One reason is that presenting an actual amount risks the work becoming dated by inflation. A price that's presented as surprisingly high can lose its impact as the value of money changes, making it difficult for a punchline or a dramatic moment to land. In this case, however, the number is so exaggerated (being around 40 times higher than the actual price of a banana), that it's unlikely for inflation to impact the joke in the immediate future. Twenty years after the episode first aired, the joke works just as well as it did.

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

:[A graph with the x-axis showing time, from the years 1950 to around 2275. The y-axis is a log scale showing the price of a banana from $0.10 to over $10.00. A label called "Price of a banana (BLS/St. Louis ''Fred''[https://fred.stlouisfed.org/])" show a rising trend in the price of a banana. There are two dots on that trend. One is labeled "Episode airs" and the other one "Now". 3 extrapolations shown as dashed lines labeled "General inflation rate", "Fresh fruit price trend" and "Banana price trend" extend until reaching the $10 mark, indicated by 3 dots.]

:[Caption above the graph:] "It's one banana, Michael. What could it cost? $10?"

:[Caption below the panel:] That line probably has another century or so left.

{{comic discussion}}

[[Category:Line graphs]]
[[Category:Timelines]]
[[Category:Fiction]]
[[Category:Extrapolation]]
[[Category:Food]]

284: Tape Measure

2023-11-19T13:17:05Z

172.71.178.22: /* Explanation */ Heavily edited the previous version of "parenthesis paragraph" to add more oomph, detail and personal speculation. Probably could be tweaked(/corrected), but looks Okish at first outing. (Yep, just before saving, corrected a typo!)

{{comic
| number = 284
| date = July 2, 2007
| title = Tape Measure
| image = tape_measure.png
| titletext = This sequence was later reproduced in the International Tape-Extending Federation archives, retitled 'The Founding of the Sport'.
}}

==Explanation==
[[Cueball]] acts childishly, finding a tape measure and then playing with it. He then extends it to 8 feet (approx. 2.5 meters), wondering whether or not that was a record, which makes him imagine a sport where extending the tape measure as far as possible was the goal.

{{w|Tape measure}} strips, of the 'spring metal' kind are manufactured with a slight inherent curve upwards, laterally, where not curved along their length (e.g. whilst still on the spool). Extending the tape straight out from the spool, the sideways curve dominates and adds structural strength to ''keep'' the relatively light tape-strip supported against gravity. By doing so, it allows fairly easy operation to extend a tape upwards (e.g. from the floor to the ceiling of a room) or for a smaller distance sideways (e.g. the width of a picture-window) without needing a second person or the extra effort of hooking the 'end hook' over something at the 'end-point' before pulling the case back fowards the 'start'. The tape can also still be bent around corners or circumferences, at the loss of local longitudinal strength and perhaps some accuracy, if a single straight-line distance isn't desired. It is this combination of flexibility and rigidity that makes such tapes so useful for common household and maintenance measurements larger than a piece of paper (for which a rigid ruler is more useful) but smaller than a property's yard area (where a surveyor's non-sprung metal tape might be laid out) and not habitually involving curves (as with a draper's cloth tape).

However, as a tape measure is extended (especially horizontally), the weight of the strip eventually does overcome the support offered by the bend, causing it to collapse. As cleverly depicted in the comic, a single point tends to 'crumple' (often where vibrations from the handling induce a resonance; and tending towards where the cantilever forces are greatest, near where the operator is currently drawing the tape out) and this then causes a collapse in which other bends introduce themselves from the dynamics of the tape in motion and the force of its impact on the ground/other objects.

Skillfully and steadily holding the tape measure at an angle can redirect some of the weight load, reduce the momentary tendencies to cross the 'bending threshhold' and allow for a longer total extension. Vertically, it is likely that most such tape can support itself (with minimal care) against collapse, but would reach no length at all in a sideways direction. The ultimate aim of those who attempt idle 'tape extending' challenges is often to achieve the longest ''horizontal'' extension. Or the highest 'figure' revealed from the tape, whilst doing so, which would actually be the length of the slightly arced diagonal, but would be fairly close to the slightly smaller 'reach length' attained, and usually good enough for idle entertainment. However, it is implied that this technique can be explored to the point of becoming its own sport, at which point one presumes that professional "competitive tape extension" would rely solely upon the observed horizontal extension (without, or prior to, hitting the ground), with competitor's chosen extension techniques with their standard (competition-grade) tapes perhaps even making on-tape graduations unnecessary and totally irrelevent.

The title text refers to a future where this sport exists, and this comic is a representation of the origin of this sport.

==Transcript==
:[Cueball finds a tape measure.]
:Cueball: Hey, a tape measure.

:[Cueball extends the tape measure.]
:''extend extend''

:[The tape measure falls.]
:''clatter''

:[Cueball tries again.]
:''click''
:''schwoop''

:''extend extend''

:''extend''

:Cueball (thinking): Ooh, eight feet. I wonder if that's a record.

:[Cueball imagines an olympic stadium, with three people extending tape measures]
:Audience: ''Gooo! Goooo! Gooooooo!''

==Trivia==
*During the real-life meet-up at the time & place mentioned in [[240: Dream Girl]], fans [https://web.archive.org/web/20160605010651/http://thephoenix.com/boston/news/48208-wisdom-of-crowds/ participated in a tape-measure length competition].

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

2852: Parameterball

2023-11-08T20:20:40Z

172.71.178.22: /* Explanation */

{{comic
| number = 2852
| date = November 8, 2023
| title = Parameterball
| image = parameterball_2x.png
| imagesize = 518x371px
| noexpand = true
| titletext = The ball's density also varies, but players don't learn the value until after choosing their raquets. The infamous 'bowling ball table tennis' region of the parameter space often leads to equipment damage.
}}

==Explanation==
{{incomplete|Created by a BALL THE SIZE OF 3.14 BEACH BALLS, HEAVIER THAN A CUBIC METER OF CONCRETE, FLYING OVER A NET SHORTER THAN AN ANT, ON A FIELD THE SIZE OF NEW JERSEY - Please change this comment when editing this page. Do NOT delete this tag too soon.}}

A racquet (very commonly spelled "racket", but misspelled as "raquet" in the comic) game is a 2-{{w|Doubles|or-4}} player point game, with a net, ball ({{w|Badminton|or shuttlecock}}, a racquets for each participant, and a court. The objective of the game, often, is to hit the ball in a way that it bounces on your opponent's side in a way that it hits the floor within the playing area before they attempt to hit it back onto your side. Two notable examples of this kind of game are {{w|Tennis}} and {{w|Table Tennis}} (also known as Ping-Pong), which demonstrate the potentially different scales of playing area, ball and net.

In this comic, a game called "Parameterball" is proposed, where net size, ball size, and court size are randomized every quarter. There are 4 different instances of Megan and Cueball playing this game, each in one corner, so we can assume all four of these were used within the same game of Parameterball. The different examples provide insight into the absurd games that may be played in Parameterball, depending on how mismatched the racket, court, and ball size are.

It’s unknown whether the parameters of Parameterball are unlimited or limited to what human players can reasonably work with. Assuming that the comic shows the full breadth of options, here are the approximate, apparent upper and lower limits of the 4 parameters mentioned:

{|class = "wikitable"
! Parameter !! Apparent Lower Limit !! Apparent Upper Limit
|-
| Ball Size || Ping pong ball || Human hamster “Zorb” ball
|-
| Court Size || Large board game board || NHL ice hockey rink (square corners)
|-
| Net Height || Screwdriver || Giraffe
|-
| Density || Ping pong ball || Bowling ball
|-
|}

The title text mentions that the ball's density is also randomized, and that an infamous incident where the net size, ball size, and court size were similar to that of a Ping-pong match, but with a ball as dense as a {{w|Bowling ball|bowling ball}}, not only led to equipment damage, but does so regularly. Despite this, the participants ''do not'' learn the density until ''after'' the racquet is chosen, meaning that they have no way of determining whether the racquet they chose is durable enough until it's already too late. (Choosing an excessively robust item could be detrimental to trying to play with a light ball, conversely, as it proves detrimental to reacting against volleys by a more aptly-equipped opponent.)

Randall may have been inspired by {{w|Pickleball}}, a type of racquet sport rising sharply in popularity in the US at the time this comic came out. Pickleball is a middle-ground of tennis and table tennis, with an intermediate-sized ball, court, and net height. Randall may have noticed the distinct parameters of pickleball’s elements compared to its cousin sports and was inspired to imagine a scenario in which such parameters might be randomized.

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

:[Megan and Cueball are playing a game that looks similar to tennis. There are courts, but on each multiple parts of the game are different. On each, Cueball is on the right and Megan is on the left.]
:[Top left: The court is small, each half slightly wider and deeper than a person is tall, and the ball is extremely large, about twice the height as the players' heads. The ball has just bounced on Cueball's side very slowly, and he is about to hit it.]
:[Top right: The court, ball, and net closely match a regular tennis game, albeit perhaps a slightly more ground area than a doubles' court. Cueball has just hit the ball, and it is currently flying towards Megan's side.]
:[Bottom left: The ball, and net are basically the same as in table tennis, but the 'court' is a much smaller tabletop. The ball has just bounced back up on Megan's side, and she is poised to hit it back.]
:[Bottom right: The court is slightly larger than the top left, while the net and ball are massive, with the ball at least double the radius and the net significantly over twice the height of the players. Cueball is apparently fighting to push the huge ball high enough to get over the net, indicated by movement lines in which he is barely managing to keep the ball on the racquet itself, not to mention he has only gotten the ball halfway up the net.]

:[Caption below the panel:]
:Parameterball is a raquet [sic] game divided into four quarters, with ball size, court size, and net height randomized each quarter.

{{comic discussion}}

2825: Autumn and Fall

2023-09-06T22:25:48Z

172.71.178.22: /* Explanation */ Sorting out a rogue paren, and other rewriting tweaks.

{{comic
| number = 2825
| date = September 6, 2023
| title = Autumn and Fall
| image = autumn_and_fall_2x.png
| imagesize = 392x212px
| noexpand = true
| titletext = Of course in reality this is just a US/UK thing; in British English, 'fall' is the brief period in between and 'autumn' is the main season.
}}

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

{{w|Autumn}}, also known as "fall" in the United States, is the season between summer and winter. These terms are used interchangeably, but Randall in this comic treats them as separate seasons. His timeline uses "autumn" as the season between the end of summer and the "{{w|September equinox|fall equinox}}", and the season of "fall" as the period after that until winter. Of course, there are only 4 seasons, not 5.{{Citation needed}}

The comic depicts two of the three possible boundaries, for any given hemisphere, for the recognised end of summer.
* Some treatments of the seasons (not shown) treat the summer solstice very much as "midsummer", and all other seasons also more or less equally straddling their own equinoxes/remaining solstice, putting the seasonal boundaries half way between each of these astronomically significant points.
* For others, the equinoctial/solstitial dates are used for the changeover time, so that autumn/fall starts upon the equinox (shown) and ends at the astronomically shortest day which is then the start of winter. This system tends to be traditional where the annual warming and cooling of the climate significantly 'lags' the solar calendar.
* Meteorological seasons are handily aligned to months, for administrative reasons. Spring is March through May, summer across June to August, the September start (to the close of November) is as illustrated, leaving winter to be covered by December and on until the end of the following February. Or shifted round by two of the triples for the southern hemisphere.

The title text "reverses" these 2 extra seasons, as the term "autumn" is more commonly used in the UK, compared to "fall" in the US.

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

{{comic discussion}}

[[Category:Time]]
[[Category:Timelines]]

Talk:1061: EST

2023-09-03T15:27:14Z

172.71.178.22:

"24 hours 4 minutes" because the period of rotation of the Earth is 24 hours MINUS four minutes.

EST = Eastern Standard Time (USA) or England Standard Time (UK); there's no easy way to disambiguate this since it is a common time zone for English speakers in the USA and UK.

"Run clocks backward" a possible reference to the leap second.

"0.9144" because 1 yard = 0.9144 meters

"triple 4 hours after every full moon" = add on an additional 12 hours every full moon, to make the time between full moons exactly 30 "days" (in real life it's 29.5 days). [[Special:Contributions/75.103.23.206|75.103.23.206]] 21:44, 7 December 2012 (UTC)

: Erm, just like to say, as a UK resident for all my life (five decades, adult and child), that I've ''never'' heard of "English Standard Time". GMT is Greenwich ('Gren-itch') Mean Time, which is ''for most purposes'' the same as UTC (which officially took over in the early 70s, but most lay-people still ''say'' 'GMT') and all the various other prime standards in use (give or take leap seconds, planetary rotation/orbitting adjustments, adherence to atomic clocks, etc) and BST (British Summer Time, i.e. GMT+1)has just taken over for this sun-tilted part of the year. A brief check of the usual reference sites reveals no sign of EST existing any time since any form of standardised "Railway Time" was originally instituted in the days of the Industrial Revolution, but I might have missed it.

: Anyway, as such, the two ESTs is surely a constructed part of the joke not (as I read it) some fact from RL that needs explaining. Yes, there's EST (Eastern Standard Time) for the US (and versions for Australia and elsewhere?), as well as main Egyptian time-zone and European Summer Time (actually a over-term for the three varieties: Western, Central and Eastern). (The UK roughly matches up to Western European Time and Western European Summer Time accordingly, but that's by no means official except possibly by convention/shared heritage of definition.) But I think the joke with the two 'EST's is ''purely'' to do with something like the whole Yard/Metre(/Meter) thing. Although initially I imagined it might be something to do with UK/US Gallon differences, albeit that we now tend to have to use Litres. Or, if you prefer, 'Liters'. ;) [[Special:Contributions/178.99.20.83|178.99.20.83]] 21:49, 1 April 2013 (UTC)

I seem to recall that Narnia time ran usually much faster but sometimes much slower than real-world time. [[Special:Contributions/130.160.145.224|130.160.145.224]] 20:51, 10 March 2013 (UTC)

I always thought that Taiwan, Province of China missed a golden opportunity here to establish propaganda that they founded it. Instead they are known as a township in the US. [[Special:Contributions/66.88.136.254|66.88.136.254]] 20:01, 13 March 2013 (UTC)

Think of what Jack Bauer could have done with 4 more minutes! {{unsigned ip|108.162.254.101}}

Not all possible attempts to make the calendar simpler would make it as complicated (or worse) than it is. For example, removing one day each from January and August to make February have 30 or 31 like the rest of the months would make the calendar (slightly) simpler and more logical going forward.[[Special:Contributions/173.245.50.174|173.245.50.174]] 18:39, 7 September 2015 (UTC)
:You'd have to rewrite {{w|Zeller's congruence}} and find a replacement for the {{w|Knuckle mnemonic}}, both of which depend upon the existing pattern, or you'd upset a lot of people!
:For the former, it relies upon the pattern of starting after February and observing that the days are 31,30,31,30,31 for March...July, the same again August...December and starting the same pattern again for January and, as far as it goes, February. Adjusting Zeller to use 12/5ths instead of 13/5ths might work out well. That seems (...back of an envelope calculation) to allow for 31 day months being March, ''June'', August, ''November'' and January (italics were 30 days), all the rest being 30 (demoting four previously 31-day months) except for the leap-February for which the ''extra''-extra-day causes no knock-on-effects.
:But you also ''could'' bring down every month to 30 days (use the factor 10/5ths, or actually just assuming the straight constant shift of +2 weekdays per month without needing to round down anything at all), except February which now has 35-or-36 days.
:(Even simpler, every month other than Feb could be 28 days - see how ''they'' like it, and Feb now be more than double the size to make up for historical wrongs. Which'd be reason enough to retain the year-downshift of Jan/Feb, but otherwise removes any month-number terms in Zeller, just the (adjusted) year-number bits because the year still ≠mod7 days.)
:...but I'd be sad to lose the Knuckles coincidence. Whatever other 'improvememts' you might think I'm suggesting! [[Special:Contributions/172.71.178.22|172.71.178.22]] 15:27, 3 September 2023 (UTC)

This might be a reference to the old TV show Babylon 5 here, but that's unlikely because the show is never mentioned anywhere else.[[Special:Contributions/208.97.36.166|208.97.36.166]] 3:18, 11 September 2015 (UTC)

Perhaps it's just a coincidence, but it should be noted "1958" could also refer to the Discordian calendar, in which that is the year 3125 (5^5, 5 being the by far most significant number in a religion especially obsessed with numerology).--[[Special:Contributions/141.101.105.29|141.101.105.29]] 22:10, 7 October 2015 (UTC)

The historical Jewish calendar did have month names; four of them happen to come up in the Old Testament. Some do suspect that the names were only used rarely.<br>The modern Japanese calendar - and I think a few others - does have numbered months only; don't recall if any historical ones do, unfortunately. [[Special:Contributions/141.101.80.44|141.101.80.44]] 09:53, 8 October 2015 (UTC)

: I agree that the connection to the Jewish (or for that matter Japanese) calendar is nonexistent. Will remove. [[User:Jkshapiro|Jkshapiro]] ([[User talk:Jkshapiro|talk]]) 02:58, 10 July 2020 (UTC)

Talk:2822: *@gmail.com

2023-08-31T03:18:20Z

172.71.178.22:

Why not send to *@*.*? [[Special:Contributions/172.69.247.45|172.69.247.45]] 03:08, 31 August 2023 (UTC)
:Either *@* suffices (if not just a *), or (because of non-standard wildcard parsing) it would reach neither ''<whatever@mydomain.me.uk>'' nor ''<something@business.com.au>''... But it'd depend upon how you invoke the query of the relevent MXRecords. [[Special:Contributions/172.71.178.22|172.71.178.22]] 03:18, 31 August 2023 (UTC)