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2892: Banana Prices

2024-03-01T02:31:09Z

Khjvcgfxgfhcgvjh: /* Discussion of price references in fiction */ Period

{{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==
[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.

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]]).
* '''Extrapolation''' is also a theme in [[605: Extrapolating]] and [[1007: Sustainable]].

===Discussion of price references in fiction===
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.

==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]]

2838: Dubious Islands

2024-02-23T04:51:17Z

Khjvcgfxgfhcgvjh: /* Explanation */ Grammar and punctuation

{{comic
| number = 2838
| date = October 6, 2023
| title = Dubious Islands
| image = dubious_islands_2x.png
| imagesize = 740x1040px
| noexpand = true
| titletext = Running for office in Minnesota on the single-issue platform 'dig a permanent channel through the Traverse Gap because it will make this map more satisfying.'
}}

==Explanation==
The definition of "island" is a piece of subcontinental land completely surrounded by a body (or perhaps bodies) of water. In most cases we don't count rivers and canals as the surrounding bodies,{{Actual citation needed}} although small pieces of land like Manhattan are exceptions, as is any bit of land entirely surrounded by the ''same'' watercourse, that splits around it. Inland islands surrounded by rivers can be called a [https://www.merriam-webster.com/dictionary/holm "holm"].

In this comic, however, Randall considers various large parts of {{w|North America}} as "dubious" islands because they're separated from other parts of the continent by various major rivers, canals, and large lakes. The repetition between the title "Dubious Islands" and the in-image label "Dubious Islands of North America" emphasizes the "Dubious-ness" of this map.

Randall's map's "Dubious Islands" are indeed not to be trusted — they leave out many less prominent rivers and canals which would break the map into many more additional "islands". For example, southern Nova Scotia, southern New Jersey, and the nearly 60-mile-long "Grand Strand" of South Carolina are also islands by the sense used here in recognizing the Cape Cod Canal as creating an island. These and many other omissions would be errors — except that Randall clearly labelled his islands "Dubious" (not to be trusted) from the start, and he is presumably well-aware of this map's stretching of reality.

The geography around the area known as {{w|Parting of the Waters}} explains the connection between the Yellowstone and Snake Rivers shown. {{w|Isa Lake}} drains into both the Snake River (via the Lewis River) and the Madison River (via the Firehole River), explaining the connection there. It is unclear why {{w|Divide Creek}}, which connects Hudson Bay to the Columbia River, or {{w|Committee's Punch Bowl}}, which connects the Arctic Ocean with the Columbia River, are not shown on this map.

The title text suggests that the map could be improved by digging a canal through the {{w|Traverse Gap}}, thereby splitting the large red "island" into two smaller "islands" with more pleasing shapes. Randall proposes to run for office in Minnesota (where the Traverse Gap is located) on the platform of digging this canal. This is unnecessary and would create little benefit to residents,{{Actual citation needed}} but constituents who like interesting maps might vote for him.

These islands are possibly Randall's humorous interpretation of the possible effects of drastic erosion (perhaps caused by continued climate change) inducing increased water movement. Sea level rise might also provoke some of these disconnections, but as some of the connecting waterways exist at over 7000 feet (over 2km) in elevation, this would require a worldwide {{w|rise in sea-level}} (and/or localised {{w|Atlantis|fall of land}}) that would cause other changes to the map of North America.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}
:[Title:] Dubious Islands of North America
:[Subtitle:] And the waterways that separate them

:[A map of mainland North America, down to the Panama isthmus. It is internally separated by various waterways, given labels or otherwise.]

:[Separating land approximating Nunavut (with some Northern Territories) from neighbouring Canada:] Mackenzie Athabasca Churchill

:[Comprising the much of the remainder of Canada, much of the northern United States (including Alaska), additionally separated by:] Columbia Snake Madison Missouri Chicago [Unlabelled, some of the Great Lakes and the channel past Quebec]
::[An incursive gap near the central point, from the north:] Nelson Red
::[An internal label, with arrow:] Traverse Gap
::[An incursive gap near the central point, from the south:] Mississippi
::[A separate fragment of land south of the Madison, in the western half of the land-mass, bordered to its south by:] Yellowstone
::[A small fragment off the southen part of the western edge, an arrow and a label:] Chehalis/Black Lake

:[Nova Scotia, New Brunswick and parts of the adjacent US, disconnected by:] Champlain Hudson
::[Label with an arrow on the east coast:] Cape Cod Canal

:[A small triangle of territory, further isolated by:] Erie

:[Most of the Eastern Seaboard of the US, additionally divided off by:] Tombigbee
::[Fragment of land shorn from the northern part of the eastern edge, label with arrow:] Chesapeake and Delaware Canal
::[Fragment of land shorn from the tip of Florida, label with arrow:] Okeechobee Waterway

:[Strip of land west of the Tombigbee, bounded also to its west by:] Mississippi
::[Fragment of land immediately to its south, with a nearby label and arrow:] Atchafalaya

:[The remainder of the continent; comprising much of the US, all of Mexico and various central American territories, with a final tip of the eastwards-bending isthmus:] Panama Canal

{{comic discussion}}
[[Category:Maps]]
[[Category:Comics with color]]
[[Category:Politics]]