Editing 2892: Banana Prices

{{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 $10 BANANA - Please change this comment when editing this page. Do NOT delete this tag too soon.}}

[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, "Visiting Ours", 2003) that became well known as a meme used to mock out-of-touch elites. The character who spoke this line -- Lucille Bluth, a rich socialite -- didn't know whether a banana cost $10 in 2003 because she never did any grocery shopping "because we have people for that."  According to the graph, the banana price at the time of that episode was actually just under 25 cents.

'''This comic has many layers of meaning and uses an "unreliable narrator" device to initially mislead the reader and to ultimately make its point about the unreliabilty of simplistic extrapolation and how easy it is to be fooled by false precision.'''

At first, the comic looks like a wry observation that the irony of this sitcom line will be obsolete in a century or two. This comic shows three different "linear" extrapolations of the current increasing trend in banana prices, using a graph of historic banana prices and a series of projected future prices based upon relevant price trends. The comic seems to say that the irony of the sitcom quote is likely to be anachronistically meaningless within a century or two, assuming these particular extrapolations are accurate.

(While these extrapolations look linear, they are in fact logarithmic, since a straight line extrapolation on a graph with a logarithmic scale is actually a logarithmic extrapolation. The graph is drawn to a logarithmic vertical scale on the vertical (left) axis, which makes it possible to visualize exponential price-rise as the dotted line.)

Upon closer inspection though, it's apparent that the caption-writer is making some absurd assumptions about inflation continuing as its current, unusually high level. The caption writer, in this case, is an unreliable narrator who is ''also'' as humorously out-of-touch as Lucille Bluth, but in a different way. If inflation returns to its recent historic norm of 2%, as it is rather likely to do, then it will actually take many centuries for the price of a banana to rise past $10. The current rate of inflation – around 5% in the US – is much higher than the historical average from the past several decades, and if recent historical trends dominate, inflation is likely to revert back to the more typical 1-to-2% range in the near term (next 5 to 10 years), and is rather unlikely to continue at 5% for the next century. 

The title text is a wink from Randall about this unreliable narrator by using the ignorant tone of Lucille Bluth to wryly acknowledge that, in fact, that error of the extrapolations greatly exceeds 10%. Just as Lucille was very wrong about a $10 banana (a price threashold), so too is the Lucille of the title text wrong about the 10% error (a proportional change). It does so in the form of a meta-joke about the false precision of extrapolations, while continuing the theme of the speaker's extreme ignorance. Assuming that the error couldn't be more than 10% shows that the Lucille speaker continues to be hilariously off-base, presuming far more accuracy from a multi-century prediction than is warranted.

'''Overall, the comic is a clever commentary about the false precision of extrapolation and how easy it is to be fooled by it.''' It does so by initially fooling the reader with an imprecise extrapolation, wrapping it all in a pop-culture reference. The ultimate point is that any extrapolation into the distant future based on past data points is just an educated guess likely to be quite wrong, with an expected error far in excess of 10%. 

Besides the inflation example, another way the extrapolation could be wrong was if -- in the next 100 years -- there was a massive banana crash or {{w|Gros Michel banana|extinction}} due to {{w|Banana#Pests, diseases, and natural disasters|supply issues}}, in which case the sharply recuded supply of bananas could send the price past $10 very quickly.

Log scales are a recurring XKCD theme, and this is the second comic in a row to involve logarithms (the prior one being [[2891: Log Cabin]]). It's also the second comic in the last four to involve prediction across centuries (i.e. [[2889: Greenhouse Effect]]).

==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. 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 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 comic : That line probably has another century or so left.

{{comic discussion}}
@@ Line 10: / Line 10: @@
 ==Explanation==
-[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. 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.
+{{incomplete|Created by a $10 BANANA - Please change this comment when editing this page. Do NOT delete this tag too soon.}}
-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.
+[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, "Visiting Ours", 2003) that became well known as a meme used to mock out-of-touch elites. The character who spoke this line -- Lucille Bluth, a rich socialite -- didn't know whether a banana cost $10 in 2003 because she never did any grocery shopping "because we have people for that."  According to the graph, the banana price at the time of that episode was actually just under 25 cents.
-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.
+'''This comic has many layers of meaning and uses an "unreliable narrator" device to initially mislead the reader and to ultimately make its point about the unreliabilty of simplistic extrapolation and how easy it is to be fooled by false precision.'''
-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.
+At first, the comic looks like a wry observation that the irony of this sitcom line will be obsolete in a century or two. This comic shows three different "linear" extrapolations of the current increasing trend in banana prices, using a graph of historic banana prices and a series of projected future prices based upon relevant price trends. The comic seems to say that the irony of the sitcom quote is likely to be anachronistically meaningless within a century or two, assuming these particular extrapolations are accurate.
-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.
+(While these extrapolations look linear, they are in fact logarithmic, since a straight line extrapolation on a graph with a logarithmic scale is actually a logarithmic extrapolation. The graph is drawn to a logarithmic vertical scale on the vertical (left) axis, which makes it possible to visualize exponential price-rise as the dotted line.)
-The title text continues the ignorant tone of Lucille Bluth to make two jokes.
+Upon closer inspection though, it's apparent that the caption-writer is making some absurd assumptions about inflation continuing as its current, unusually high level. The caption writer, in this case, is an unreliable narrator who is ''also'' as humorously out-of-touch as Lucille Bluth, but in a different way. If inflation returns to its recent historic norm of 2%, as it is rather likely to do, then it will actually take many centuries for the price of a banana to rise past $10. The current rate of inflation – around 5% in the US – is much higher than the historical average from the past several decades, and if recent historical trends dominate, inflation is likely to revert back to the more typical 1-to-2% range in the near term (next 5 to 10 years), and is rather unlikely to continue at 5% for the next century.
-# 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.
+The title text is a wink from Randall about this unreliable narrator by using the ignorant tone of Lucille Bluth to wryly acknowledge that, in fact, that error of the extrapolations greatly exceeds 10%. Just as Lucille was very wrong about a $10 banana (a price threashold), so too is the Lucille of the title text wrong about the 10% error (a proportional change). It does so in the form of a meta-joke about the false precision of extrapolations, while continuing the theme of the speaker's extreme ignorance. Assuming that the error couldn't be more than 10% shows that the Lucille speaker continues to be hilariously off-base, presuming far more accuracy from a multi-century prediction than is warranted.
-This comic uses several common xkcd themes:
+'''Overall, the comic is a clever commentary about the false precision of extrapolation and how easy it is to be fooled by it.''' It does so by initially fooling the reader with an imprecise extrapolation, wrapping it all in a pop-culture reference. The ultimate point is that any extrapolation into the distant future based on past data points is just an educated guess likely to be quite wrong, with an expected error far in excess of 10%.
-* '''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]]).
-* '''Extrapolation''' is also a theme in [[605: Extrapolating]] and [[1007: Sustainable]].
-===Discussion of price references in fiction===
+Besides the inflation example, another way the extrapolation could be wrong was if -- in the next 100 years -- there was a massive banana crash or {{w|Gros Michel banana|extinction}} due to {{w|Banana#Pests, diseases, and natural disasters|supply issues}}, in which case the sharply recuded supply of bananas could send the price past $10 very quickly.
-It's common for fictional works to {{tvtropes|UndisclosedFunds|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.
-While the graph is about ordinary bananas, technically Lucille may have been guessing the price of frozen and chocolate-dipped bananas, which sold for $1 to $4 in the early 2000s. The only thing this changes is the interpretation of her estimate as perhaps being slightly less out-of-touch.
+Log scales are a recurring XKCD theme, and this is the second comic in a row to involve logarithms (the prior one being [[2891: Log Cabin]]). It's also the second comic in the last four to involve prediction across centuries (i.e. [[2889: Greenhouse Effect]]).
-===Panama disease===
-The banana price can possibly be highly affected by the {{w|Panama disease}}:
-<blockquote>During the 1950s, an outbreak of Panama disease almost wiped out commercial Gros Michel banana production. The Gros Michel banana was the dominant cultivar of bananas, and Fusarium wilt inflicted enormous costs and forced producers to switch to other, disease-resistant cultivars. Since the 2010s, '''a new outbreak of Panama disease caused by the strain Tropical Race 4 (TR4) has threatened the production of the Cavendish banana, today's most popular cultivar'''.</blockquote>
 ==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.]
+:[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. 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 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 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.
+:Caption below comic : That line probably has another century or so left.
 {{comic discussion}}
-[[Category:Line graphs]]
-[[Category:Timelines]]
-[[Category:Fiction]]
-[[Category:Extrapolation]]
-[[Category:Food]]