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2024-03-29T02:13:08Z
User contributions
MediaWiki 1.30.0
https://www.explainxkcd.com/wiki/index.php?title=2000:_xkcd_Phone_2000&diff=164821
2000: xkcd Phone 2000
2018-10-26T13:06:00Z
<p>172.68.90.22: Changed wind to woodwind, as woodwind is a type of wind instrument, as is brass.</p>
<hr />
<div>{{comic<br />
| number = 2000<br />
| date = May 30, 2018<br />
| title = xkcd Phone 2000<br />
| image = xkcd_phone_2000.png<br />
| titletext = Our retina display features hundreds of pixels per inch in the central fovea region.<br />
}}<br />
<br />
==Explanation==<br />
This is the seventh entry in the ongoing [[:Category:xkcd Phones|xkcd Phone series]] after [[1889: xkcd Phone 6]]. This time a nonconsecutive version number is used to match the milestone comic number.<br />
<br />
List of features (clockwise from top-center):<br />
<br />
*'''Dockless:''' It was common practice for older standard cellphones (i.e. non-smartphones) to use a docking station for charging. "Dockless" could be a catchy marketing term for wireless charging, or it could simply mean wired charging without a dock.<br />
*'''Silent:''' Most mobile phones have a "Silent" mode in which all ringing and vibration is muted, so the user can receive messages and missed-call notifications in a place that requires silence. This xkcd Phone feature may be a "Silent" mode button, but perhaps the phone is silent all the time and unable to produce sound at all. While most people these days use their smartphones for functions that do not require sound, a completely silent phone would not fit the traditional definition of a "phone". This feature is labelled at the location where a headphone socket would traditionally be, although some recent phones have discarded the traditional headphone jack in place of wireless headphones.<br />
*'''Quad camera takes four copies of every picture:''' Recent phones have added up to three rear-facing cameras, offering different fields of view, monochrome cameras for low light, and a wider base for emulating depth of field effects. At the time of writing no phone on the market has four rear-facing cameras. However, YouTube personality nigahiga created a parody of the iPhone (iFhone 8) that has four cameras structured similarly, e.g. taking a picture of a letter K gives 4K. An alternative interpretation is that the cameras take four ''identical'' pictures simultaneously, which would use up storage space at 4 times the rate of a standard camera while providing no advantage.<br />
*'''Front-facing camera obscura:''' A {{w|camera obscura}} is a dark room or box with a small hole allowing light to enter. The size of the hole causes light travelling in straight lines to project a dim inverted image on the back of the room or box; the concept is the predecessor to a modern camera, which uses a lens to allow more light to enter. A camera obscura is not strictly speaking a camera as in an image capture device (although there are pin-hole cameras which use the same mechanism). Actual phones have front-facing conventional cameras, allowing selfies, video calling, etc.<br />
*'''3D facial contour analysis shows you a realistic preview of your death mask:''' Recent computational photography effects implemented on mobile phones support facial analysis, allowing for artificial relighting or the creation of avatars. However, since a {{w|death mask}} is created to look just like the deceased's face, all cameras provide this "feature" automatically.<br />
*'''Sponsored pixels:''' Presumably this means that parts of the screen (pixels) can be bought in a sponsoring deal. If enough pixels are sold, your screen would be rendered unusable. It is common for advertisers to buy part of the screen real-estate on a service web site (in fact, {{w|The Million Dollar Homepage}} hosted nothing but a 1000x1000 pixel grid of advertisements), and "images" the size of individual pixels can be used to track site access without being intrusive to the user. For the xkcd Phone 2000, it appears that advertisers have access to part of the screen (worryingly, right in the middle). Slightly less intrusive approaches have been used in bookstores selling customised versions of the Kindle, for example, and it is common for cell phone networks to insist on network-specific software to be installed on a phone. <br />
*'''Front and rear pop-out grips:''' There are accessories that stick to the rear of a phone and can be "popped out", offering a grip, a stand, or somewhere to store headphone cables. Integrating such a feature into the phone design is novel, although some phones have incorporated kick stands. Pop-out grips are normally placed on the back of the phone to make it easier to hold with one hand. Having a second grip to the front of the phone does nothing except block part of the screen. There could be a small screen on the top of the grip since the grip is shown to contain "Sponsored Pixels".<br />
*'''Humidity-controlled crisper:''' A crisper is a drawer in a refrigerator meant to control the humidity to keep vegetables from drying out and getting limp. Obviously, a smartphone would have no need for a crisper.<br />
*'''Antikythera mechanism:''' The {{w|antikythera mechanism}} is an ancient Greek clockwork device for predicting astronomical positions. It is one of the earliest known analogue computers. While impressive for its time, by now it is obsolete by millennia.<br />
*'''New York Times partnership: all photos taken with camera app are captioned in real time by reporter Maggie Haberman:''' Modern phones can use machine learning techniques (usually in the cloud) to identify and tag camera content - this makes it possible to search, for example, for photos containing a particular person or subject without requiring user input. Cellphone photos are often used in contributions to social media with some form of user-provided caption. This phone appears to combine the two, using {{w|Maggie Haberman}} to provide automatic captions for photos taken by the phone's owner (although whether this is explicitly for social media use or internal to the phone is unclear).<br />
*'''Spit valve:''' A water key, or "spit valve," is a feature on most brass and some woodwind instruments used to empty the instrument of condensation caused by the musician's breath (and not, as is commonly thought, saliva). Of course, one wouldn't think condensation would form on the inside of a smartphone.<br />
*'''Standard USB connector:''' a USB A port is displayed. Unfortunately, a "standard" USB connector, according to the USB standard, would be a USB B port as a phone typically acts as the "slave" device, rather than the "host" as a USB A port would imply. However, in recent updates to the USB standard, bi-communication between 2 A ports is supported<br />
*'''Coin purse-style squeeze access:''' presumably, the casing is flexible in this region, and when squeezed at the sides (a bad idea, considering the next design item) reveals the USB A port and spit valve.<br />
*'''Hollow-ground:''' a {{w|Grind#Typical_grinds|hollow grind}} is a type of knife (or similar sharp tool) edge noted for sharpness and general fragility, often seen in razors. This seems to imply that the phone is exceedingly smooth, which would make it difficult to hold{{Citation needed}}.<br />
*'''Absorbent:''' Many modern phones are designed to be waterproof, to avoid accidents and allow use in the rain. It's also common to have some form of oleophobic coating on the screen to reduce smearing as fingers are used on the touchscreen. This phone seems to have the reverse feature, and be explicitly designed to absorb things (presumably liquids--perhaps that's why it needs a spit valve). "Absorbent" is more commonly a property touted by the packaging of paper towels.<br />
*'''Keyboard supports dynamic typing:''' {{w|Type_system#Dynamic_type_checking_and_runtime_type_information|Dynamic typing}} is a computer programming concept, and has nothing to do with typing on a keyboard.<br />
*'''Backflow preventer:''' A {{w|backflow prevention device}} is a mechanism that avoids the possibility of liquid (usually water) travelling in the opposite direction from the normal intent if the expected pressure is inverted. Since there is not normally any liquid flowing through a phone (unless in this case relating to the spit valve), this would not normally be a useful feature. However, some smart phones do contain pressure measuring devices such as barometers (which can also be used in some cases to detect the phone being squeezed), so maybe this phone is intended to be resilient to such conditions.<br />
*'''Swiss Army partnership: folding knife (unlocks only if Switzerland is invaded):''' A {{w|Swiss Army knife}} is a folding knife, traditionally with many secondary "blades" for multiple uses such as can openers and files. Usually it is a generic term for that style of knife, but the knife in this phone surprisingly really has a connection with the army of {{w|Switzerland}}. Switzerland is known for remaining neutral (and not being invaded) in both of the World Wars of the 20th century despite war raging across surrounding countries, suggesting that it is unlikely that the knife would ever be unlocked. While such a feature on a phone (or phone case) may be useful, it is likely to be a safety concern, and a threat to convenience when security checkpoints such as airports start confiscating the phone when they notice it conceals a knife blade. What's more, a phone does not provide the ideal grip for a knife blade - especially if force is to be applied to it. This may also reference the Swiss military practice of soldiers keeping military rifles in their private homes but only being given ammunition in the event the army is mobilized.<br />
*'''100% BPA-free PCB construction:''' {{w|Bisphenol A}} (BPA) is a chemical used in plastics such as waterbottles. Recent studies show that BPA can leach estrogen-like compounds into liquids, so BPA-free water bottles have become popular. PCB probably refers to a {{w|printed circuit board}}, which is made of resin-bonded fiberglass, not plastic, and which contains the electrical components that control most modern electronic devices such as phones. It may also refer to {{w|Polychlorinated biphenyl}} (PCBs), a category of persistent organic pollutants which are not used very much any more; it would be far worse than BPA for anyone concerned with the issue.<br />
*'''AMOLCD display (7-segment):''' {{w|AMOLED}} is a display technology often used in cell phones, providing thin and emissive displays. {{w|Liquid-crystal_display|LCD}} is another display technology used in phones, and works by blocking light from a separate backlight. A {{w|Seven-segment_display|7-segment display}} is a device made of seven independently-controlled segments (usually either LCD or LED) which can be used to display a single digit; as such the technology is common in traditional digital watches. In contrast most phone displays are made of a uniform high-resolution pixel grid that allows arbitrary content to be displayed, although some very old (pre-smart) cellphones and land lines did use this technology in displaying a phone number, like the {{w|MotoFONE F3}}. The technology cannot represent the entire alphabet without modification, so it is inappropriate for text messages, let alone graphics.<br />
*'''Runs on battery for the first 6 hours, then uses gasoline:''' A nod to the increased popularity of gas-electric hybrid vehicles. This would be a fantastic breakthrough for fuel cells. There have been many attempts to create a highly portable fuel cell that can be used to power phones. Although having to use gasoline instead of a USB cord would likely cause more problems for the average consumer a fuel cell does have some notable advantages over a standard lithium-ion battery. When comparing a fuel cell to a battery of equal size the fuel cell will be capable of powering an object for far longer than the battery. This includes lithium-ion batteries which are commonly used for powering phones and are typically the majority of its mass. This would mean one could shrink the size of the battery substantially yet still be able to provide the same amount of power. The smaller battery can be kept as is in order to reduce the weight of the phone or can free up space for more features to be installed into the phone. This might simply be the first xkcd phone that mentions that it does this. Provides a possible explanation to how the manufacturer of the phone is capable of fitting so many unusual features into the phone to begin with. Another advantage of a fuel cell powered phone is that it is independent from a working power grid (useful for disaster situations where thousands of people would no longer be capable of staying in contact with others or people who are stranded and alone) and there is no need for a bulky generator to convert the gasoline into electricity first. This is not the first time Randall has talked about this before, with much of the information here coming from what-if #128: {{what if|128|Zippo Phone}}.<br />
*'''Sharpie® dual stylus (dry-erase + permanent)''' Sharpie® is a brand most associated with a line of markers. While a stylus is generally a pen-like object that doesn't create markings, but instead allows finer input on a touch screen, "Dry-Erase + Permanent" implies that these are in fact markers. These would allow the user to write on the screen, but as this wouldn't allow any form on input to the phone, it would only serve as a very expensive pseudo-whiteboard. Even if they were actually styluses, having two would be of little use. Note that permanent was previously spelled "permenant", incorrectly. This was later corrected; See [[#Trivia]]<br />
*'''Mouse cursor:''' A feature of BlackBerry smartphones which has gone out of favor due to the popularity of touch screens. However, Android devices, at least, still support Bluetooth HID access, and on some devices it is possible to pair the device with a mouse (and keyboard) and access the screen through a mouse pointer. These peripherals may also be attached with {{w|USB On-The-Go}}. This can be particularly useful if the device is exporting its display to a large external screen - and {{w|Samsung_DeX|some manufacturers}} have provided tethering systems based around pairing a phone with a mouse. <!-- A mouse pointer is relatively useless when a touch screen is in use, since the user's finger usually covers the pointer. ---- Ed note: I've personally used an Android tablet with a USB mouse, and it was not useless at all; about the only thing that can't really be done with a mouse would be several gestures, such as pinch zoom --><br />
<br />
The tagline for the phone says that the marketing team hopes that 2000 still sounds like a futuristic number. It was common for a time to have futuristic science-fiction take place on or around the year 2000 (e.g. 2001: A Space Odyssey, Knight Rider 2000, Death Race 2000, Space: 1999), and many devices marketed in the late 20th century had a "2000" as part of their product name in order to sound futuristic. However, since the year 2000 was 18 years ago at the time of this comic's publication, this is no longer the case. The number 2000 also represents the fact that this is the 2000th xkcd comic.<br />
<br />
The nonsensical trademarking of xkcd Phone slogans has become even more pronounced: as well as the inapplicable-as-ever copyright symbol, the slogan is listed three times as a {{w|registered trademark}} and twice as an unregistered one – and the second of those trademark signs is itself trademarked.<br />
<br />
The title text refers to {{w|Retina Display}}, a term used to describe Apple products with higher pixel densities. The xkcd Phone marketing team would be unable to use the term due to Apple's having registered it as a trademark. Additionally, the {{w|Fovea centralis|central fovea region}} is a portion of your eye's retina containing the most densely packed photosensitive neurons (confusing the biological retina with the electronics display of the same name). {{w|Foveated rendering}} is a genuine computer graphics technique intended to increase performance by rendering with higher quality to the regions of the display where the user is looking, and lower quality at the edges of vision; it is expected to be useful for virtual reality (one of the uses for cell phones) as a way to deal with the required high pixel densities while managing power consumption. There are displays with variable density, in specialist uses, but such a feature is not practical in a phone because the whole area of the display is typically useful and needs to provide high resolution (as the user's eye moves across it).<br />
<br />
==Transcript==<br />
:[The comic depicts a smartphone showing many uncommon features. The front view shows a mouse cursor and a circle in the middle. The side view reveals the circle as something like an old photo lens from 1900 extending far above the surface and four large buttons (camera lenses) at the rear. The third view is from the top and just mentions a "hollow ground." The bottom view looks like as it was opened by a can opener and shows a big USB connector and on the right a small black connection.]<br />
:Dockless<br />
:Silent<br />
:Quad camera takes four copies of every picture<br />
:Front-facing camera obscura<br />
:3D facial contour analysis shows you a realistic preview of your death mask<br />
:Sponsored pixels<br />
:Front and rear pop-out grips<br />
:Humidity-controlled crisper<br />
:Antikythera mechanism<br />
:New York Times partnership: all photos taken with camera app are captioned in real time by reporter Maggie Haberman<br />
:Spit valve<br />
:Standard USB connector<br />
:Coin purse-style squeeze access<br />
:Hollow-ground<br />
:Absorbent<br />
:Keyboard supports dynamic typing<br />
:Backflow preventer<br />
:Swiss Army partnership: folding knife (unlocks only if Switzerland is invaded)<br />
:100% BPA-free PCB construction<br />
:AMOLCD display (7-segment)<br />
:Runs on battery for the first 6 hours, then uses gasoline<br />
:Sharpie® dual stylus (dry-erase + permanent)<br />
:Mouse cursor<br />
<br />
:Introducing<br />
:'''<big>The xkcd Phone 2000</big>'''<br />
:We're still hoping this sounds like a futuristic number®®™®©™<sup>®</sup><br />
<br />
==Trivia==<br />
The stylus was previously called 'permenant'. This was later corrected, to permanent. You can still see the original image [http://www.explainxkcd.com/wiki/images/archive/b/b4/20180531174214%21xkcd_phone_2000.png here]<br />
<br />
{{comic discussion}}<br />
<br />
[[Category:xkcd Phones]]<br />
[[Category:Comics sharing name|xkcd Phones]]</div>
172.68.90.22
https://www.explainxkcd.com/wiki/index.php?title=2063:_Carnot_Cycle&diff=164673
2063: Carnot Cycle
2018-10-24T17:44:44Z
<p>172.68.90.22: Added transcript</p>
<hr />
<div>{{comic<br />
| number = 2063<br />
| date = October 24, 2018<br />
| title = Carnot Cycle<br />
| image = carnot_cycle.png<br />
| titletext = The Carnot cycle is more properly known by its full title, the "Carnot-Tolkien-Wagner Ring Cycle."<br />
}}<br />
<br />
==Explanation==<br />
{{incomplete|No tables for texts like this! Please edit the explanation below and only mention here why it isn't complete. Do NOT delete this tag too soon.}}<br />
<br />
This comic shows a {{w|Pressure–volume diagram}} which is used in this case for a {{w|Carnot cycle}}, a theoretical thermodynamic cycle and covers most thermodynamics classes which looks very much like the figure drawn. However in this case, [[Randall]] has replaced the labels of the 4 stages of the real Carnot cycle with new ones.<br />
<br />
Each step is explained below<br />
<br />
{| class="wikitable sortable"<br />
!Step in Comic<br />
!Step in the real Carnot Cycle<br />
!Explanation<br />
|-<br />
|1. Isometric expansion. When heated, the gas becomes larger due to increasing volume<br />
|Reversible isothermal expansion of the gas at the "hot" temperature, Th (isothermal heat addition or absorption).<br />
|The comic text uses a circular argument. Additionally, "isometric" (equal dimensions) could mean that the gas does ''not'' change in volume, in contrast to the change in volume here.<br />
|-<br />
|2. Isotonic expansion. The gas expands further due to dark energy while percent milkfat remains constant.<br />
|Isentropic (reversible adiabatic) expansion of the gas (isentropic work output).<br />
|Isotonic is commonly associated with sports drink (and not thermodynamics). Dark energy is hypothesized to be a cause for the expansion of the universe.<br />
|-<br />
|3. Isopropyl compression. While inflation is held constant, the gas contracts due to tightening interest rates.<br />
|Reversible isothermal compression of the gas at the "cold" temperature, Tc. (isothermal heat rejection)<br />
|Isopropyl alcohol is commonly used for cleaning. Inflation and contraction could refer to changes in gas volume, but the reference to interest rates puts them in the context of {{w|macroeconomics}}. Raising ("tightening") interest rates tends to reduce {{w|inflation}} and/or "contract" the economy. In economics (and other sciences) to better understand model parameter relations, some parameter may be held constant in theory. This could refer to the {{w|Fisher equation}} Holding one parameter constant is also done in the Carnot cycle (for a physical parameter): not only in theory but also in practice! (In free market economies the inflation cannot be directly held constant).<br />
|-<br />
|4. Decline and fall. The gas diminishes and goes into the West while remaining Galadriel, completing the cycle.<br />
|Isentropic compression of the gas (isentropic work input).<br />
|{{w|Galadriel}} is a character in {{w|The Lord of the Rings}}. She is one of the leading {{w|Elf (Middle-earth)|elves}}, a race that in the time of the book is said to be dwindling (in number and importance) in {{w|Middle Earth}} and migrating westward to {{w|Valinor}}. Galadriel is one of the last elves to leave, after successfully resisting temptation to take the One Ring and become an all-powerful queen who dominates Middle-earth, instead saying "I will diminish, and go into the West, and remain Galadriel."<br />
|}<br />
<br />
<br />
Title text: Richard Wagner's Ring cycle consists of four operas. J.R.R. Tolkien wrote The Lord of the Rings. Their works are known as {{w|Literary cycle}}s.<br />
<br />
==Transcript==<br />
{{incomplete transcript|Do NOT delete this tag too soon.}}<br />
<br />
[A Cartesian plot in the first quadrant with axes labelled P on the Y-Axis and V on the X-Axis, with a rhombus-shaped set of four points with arrows between them]<br />
<br />
[Upper left point] <br />
1. Isometric Expansion<br />
When heated, the gas becomes larger due to increasing volume<br />
<br />
[Middle point]<br />
2. Isotonic expansion <br />
The gas expands further due to dark energy while percent milkfat remains constant<br />
<br />
[Bottom Right point]<br />
3. Isopropyl compression <br />
While inflation is held constant, the gas contracts due to tightening interest rates<br />
<br />
[Middle Left point]<br />
4. Decline and fall<br />
The gas diminishes and goes into the West while remaining Galadriel, completing the cycle<br />
<br />
<br />
{{comic discussion}}<br />
<br />
[[Category:Line graphs]]<br />
[[Category:Physics]]<br />
[[Category:LOTR]]</div>
172.68.90.22
https://www.explainxkcd.com/wiki/index.php?title=2001:_Clickbait-Corrected_p-Value&diff=163445
2001: Clickbait-Corrected p-Value
2018-09-29T14:16:31Z
<p>172.68.90.22: /* Explanation */</p>
<hr />
<div>{{comic<br />
| number = 2001<br />
| date = June 1, 2018<br />
| title = Clickbait-Corrected p-Value<br />
| image = clickbait_corrected_p_value.png<br />
| titletext = When comparing hypotheses with Bayesian methods, the similar 'clickbayes factor' can account for some harder-to-quantify priors.<br />
}}<br />
<br />
==Explanation==<br />
{{incomplete|Click here to learn more about the influence of Clickbait... But please first explain p-value. Most people don't know. And more wiki links.}}<br />
This is yet another comic dealing with [[:Category:Clickbait|Clickbait]], and is satire mocking researchers/journalists/publishers for fudging research data based on what brings in the most advertising revenue. The topic of fudging research data in academia has also previously appeared in [[882: Significant]] and [[1478: P-Values]].<br />
<br />
Clickbait is the practice of using deceptive or manipulative headlines to entice readers to click on a dubious news story, often with the purpose of generating ad revenue.<br />
<br />
[https://en.wikipedia.org/wiki/Statistical_hypothesis_testing Hypothesis testing] in statistics is a standard method to determine whether a particular hypothesis is supported by the data. For the topic given in this comic, a researcher might compare data on athletic performance with data on chocolate consumption by those athletes to determine whether the two trend together. By convention, the "null hypothesis" (designated H<sub>0</sub>) is that there's no correlation (that chocolate isn't correlated with athletic performance, in this case) and the "alternate hypothesis" (H<sub>1</sub>) is that they are correlated. (If the study consists of ''feeding'' chocolate to one of two identical groups and not the other, rather than tracking what they'd be eating anyway, then the alternative hypothesis can be strengthened to be that chocolate *causes* improved performance.) These sets are subjected to statistical tests which return a "test statistic". From that test statistic a [https://en.wikipedia.org/wiki/P-value "p-value"] is calculated. The p-value indicates the probability of observing the obtained results (or any more extreme value), when all assumptions of the test are true (including the null hypothesis). <br />
In layman's terms: <b> the p-value is the probability that the researcher sees results as extreme or more extreme than the observed result given the null hypothesis is true; [http://www.perfendo.org/docs/BayesProbability/twelvePvaluemisconceptions.pdf the p-value is NOT the probability that the null hypothesis is correct].</b> It answers the question: If there is no correlation, how likely was it that I saw a correlation at least this big? Hence, if the p-value is low enough (by convention < 0.05), the null hypothesis is rejected, and we conclude that the alternate hypothesis is supported by the data (NOT that it is "correct" or "true"). <br />
<br />
In this comic, the p-value is corrected by a factor that takes clickbait into account. This factor has the effect of increasing the p-value if H<sub>1</sub> is more clickbaity than H<sub>0</sub>, and decreases the p-value if H<sub>0</sub> is more clickbaity than H<sub>1</sub>. This suggests that whatever clickers of clickbait believe, the reverse is likely to be true.<br />
<br />
Or, another interpretation could be that this factor corrects for a selection bias effect where the p-values for more clickbaity H<sub>1</sub>s tend to be lower than they should be and p-values for non-clickbaity H<sub>0</sub>s to be higher than they should be. For example, one explanation could be that for p-values that are on the cusp of significance, researchers may be more incentivized to fudge and adjust the data to get the p-value down if the H<sub>1</sub> is highly sensational, since the H<sub>1</sub> would make the research more likely to get published and attract attention. (See also [https://fivethirtyeight.com/features/science-isnt-broken/ FiveThirtyEight's article on p-hacking] and [https://stats.stackexchange.com/questions/200745/how-much-do-we-know-about-p-hacking-in-the-wild/200752#200752 this Stack Exchange question about p-hacking in the wild].)<br />
<br />
As the statistical results now depend on people's beliefs about the hypothesis, this is as far from actual science as one can get. However, in a way, it is more in tune with a quote by Arbuthnot (one of the originators of the use of p-values) attributing variation to active thought rather than chance, "From whence it follows, that it is Art, not Chance, that governs." Randall applying that quote to the thoughts of the masses, bringing it in line with "Art".<br />
<br />
[[1475: Technically|Technically]], the comic's depiction of null and alternative hypotheses is not entirely correct. As the alternative hypothesis (H<sub>1</sub>) predicts that chocolate will ''improve performance'' (i.e., a one-tailed, directional hypothesis), the null hypothesis (H<sub>0</sub>) should predict that chocolate will do nothing ''or'' make performance worse. In other words, the alternative hypothesis should be true if and only if the null hypothesis is false. For example, alternatively, if the H<sub>1</sub> were to say that ''chocolate will change performance'' (for better or worse; i.e., a two-tailed hypothesis) then H<sub>0</sub> should say that ''chocolate will do nothing''.<br />
<br />
For the mouseover text: Bayesian methods start with a "prior", which is the probabilities believed before seeing new evidence (e.g. before conducting an experiment). Time spent reading clickbait would probably cause people to have unusual beliefs about what is likely before seeing evidence.<br />
<br />
==Transcript==<br />
:[Under a heading that says Clickbait-Corrected p-Value there is a mathematic formula. Below that is the description of the two used variables and what they mean:]<br />
:Clickbait-corrected p-value:<br />
<br />
:P<sub>CL</sub> = P<sub>traditional</sub> ∙ click(H<sub>1</sub>)/click(H<sub>0</sub>)<br />
<br />
:H<sub>0</sub>: NULL hypothesis ("Chocolate has no effect on athletic performance")<br />
:H<sub>1</sub>: Alternative hypothesis ("Chocolate boosts athletic performance")<br />
:click(H): Fraction of test subjects who click on a headline announcing that H is true<br />
<br />
{{comic discussion}}<br />
<br />
[[Category:Clickbait]]<br />
[[Category:Statistics]]</div>
172.68.90.22
https://www.explainxkcd.com/wiki/index.php?title=2001:_Clickbait-Corrected_p-Value&diff=163444
2001: Clickbait-Corrected p-Value
2018-09-29T14:03:05Z
<p>172.68.90.22: /* Explanation */</p>
<hr />
<div>{{comic<br />
| number = 2001<br />
| date = June 1, 2018<br />
| title = Clickbait-Corrected p-Value<br />
| image = clickbait_corrected_p_value.png<br />
| titletext = When comparing hypotheses with Bayesian methods, the similar 'clickbayes factor' can account for some harder-to-quantify priors.<br />
}}<br />
<br />
==Explanation==<br />
{{incomplete|Click here to learn more about the influence of Clickbait... But please first explain p-value. Most people don't know. And more wiki links.}}<br />
This is yet another comic dealing with [[:Category:Clickbait|Clickbait]], and is satire mocking researchers/journalists/publishers for fudging research data based on what brings in the most advertising revenue. The topic of fudging research data in academia has also previously appeared in [[882: Significant]] and [[1478: P-Values]].<br />
<br />
Clickbait is the practice of using deceptive or manipulative headlines to entice readers to click on a dubious news story, often with the purpose of generating ad revenue.<br />
<br />
Hypothesis testing in statistics is a standard method to determine whether a particular hypothesis is supported by the data. For the topic given in this comic, a researcher might compare data on athletic performance with data on chocolate consumption by those athletes to determine whether the two trend together. By convention, the "null hypothesis" (designated H<sub>0</sub>) is that there's no correlation (that chocolate isn't correlated with athletic performance, in this case) and the "alternate hypothesis" (H<sub>1</sub>) is that they are correlated. (If the study consists of ''feeding'' chocolate to one of two identical groups and not the other, rather than tracking what they'd be eating anyway, then the alternative hypothesis can be strengthened to be that chocolate *causes* improved performance.) These sets are subjected to statistical tests which return a "p-value", which indicates the probability of observing the obtained results (or any more extreme value), when all assumptions of the test are true (including the null hypothesis). In layman's terms: <b> the p-value is the probability that the researcher sees results as extreme or more extreme than the observed result given the null hypothesis is true; [http://www.perfendo.org/docs/BayesProbability/twelvePvaluemisconceptions.pdf the p-value is NOT the probability that the null hypothesis is correct].</b> It answers the question: If there is no difference, how likely was it that I saw a difference at least this big? Hence, if the p-value is low enough, the null hypothesis is rejected, and we conclude that the alternate hypothesis is supported by the data. <br />
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In this comic, the p-value is corrected by a factor that takes clickbait into account. This factor has the effect of increasing the p-value if H<sub>1</sub> is more clickbaity than H<sub>0</sub>, and decreases the p-value if H<sub>0</sub> is more clickbaity than H<sub>1</sub>. This suggests that whatever clickers of clickbait believe, the reverse is likely to be true.<br />
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Or, another interpretation could be that this factor corrects for a selection bias effect where the p-values for more clickbaity H<sub>1</sub>s tend to be lower than they should be and p-values for non-clickbaity H<sub>0</sub>s to be higher than they should be. For example, one explanation could be that for p-values that are on the cusp of significance, researchers may be more incentivized to fudge and adjust the data to get the p-value down if the H<sub>1</sub> is highly sensational, since the H<sub>1</sub> would make the research more likely to get published and attract attention. (See also [https://fivethirtyeight.com/features/science-isnt-broken/ FiveThirtyEight's article on p-hacking] and [https://stats.stackexchange.com/questions/200745/how-much-do-we-know-about-p-hacking-in-the-wild/200752#200752 this Stack Exchange question about p-hacking in the wild].)<br />
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As the statistical results now depend on people's beliefs about the hypothesis, this is as far from actual science as one can get. However, in a way, it is more in tune with a quote by Arbuthnot (one of the originators of the use of p-values) attributing variation to active thought rather than chance, "From whence it follows, that it is Art, not Chance, that governs." Randall applying that quote to the thoughts of the masses, bringing it in line with "Art".<br />
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[[1475: Technically|Technically]], the comic's depiction of null and alternative hypotheses is not entirely correct. As the alternative hypothesis (H<sub>1</sub>) predicts that chocolate will ''improve performance'' (i.e., a one-tailed, directional hypothesis), the null hypothesis (H<sub>0</sub>) should predict that chocolate will do nothing ''or'' make performance worse. In other words, the alternative hypothesis should be true if and only if the null hypothesis is false. For example, alternatively, if the H<sub>1</sub> were to say that ''chocolate will change performance'' (for better or worse; i.e., a two-tailed hypothesis) then H<sub>0</sub> should say that ''chocolate will do nothing''.<br />
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For the mouseover text: Bayesian methods start with a "prior", which is the probabilities believed before seeing new evidence (e.g. before conducting an experiment). Time spent reading clickbait would probably cause people to have unusual beliefs about what is likely before seeing evidence.<br />
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==Transcript==<br />
:[Under a heading that says Clickbait-Corrected p-Value there is a mathematic formula. Below that is the description of the two used variables and what they mean:]<br />
:Clickbait-corrected p-value:<br />
<br />
:P<sub>CL</sub> = P<sub>traditional</sub> ∙ click(H<sub>1</sub>)/click(H<sub>0</sub>)<br />
<br />
:H<sub>0</sub>: NULL hypothesis ("Chocolate has no effect on athletic performance")<br />
:H<sub>1</sub>: Alternative hypothesis ("Chocolate boosts athletic performance")<br />
:click(H): Fraction of test subjects who click on a headline announcing that H is true<br />
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{{comic discussion}}<br />
<br />
[[Category:Clickbait]]<br />
[[Category:Statistics]]</div>
172.68.90.22
https://www.explainxkcd.com/wiki/index.php?title=1159:_Countdown&diff=163364
1159: Countdown
2018-09-27T14:59:48Z
<p>172.68.90.22: </p>
<hr />
<div>{{comic<br />
| number = 1159<br />
| date = January 11, 2013<br />
| title = Countdown<br />
| image = countdown.png<br />
| titletext = For all we know, the odds are in our favor.<br />
}}<br />
<br />
==Explanation==<br />
The comic shows a {{w|seven segment display}} (aka [http://www.ece.mtu.edu/labs/EElabs/EE2304/pages/bcd_to_seven_segment_TAversion.html calculator-style numbers]) with a countdown. [[Black Hat]] explains that it is a countdown, maybe to a {{w|supervolcano}} eruption. However, an unfortunately placed picture blocks view of the full display. Due to the form of a seven-segment display, the first digit could be 0, 6, or 8, and five digits are completely blocked by the picture. [[Cueball]] is worried and asks him to move the picture, but Black Hat lazily or teasingly refuses to move it. <br />
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He has already teased that he doesn't know what the countdown is for. His reply can either be understood as if he do not know which one of the ({{w|Supervolcano#VEI_8|seven potential}}) supervolcanos it is counting down to, or to which other {{w|Global catastrophic risk|cataclysmic event}} it is a countdown for (such as a {{w|Impact event|meteor strike}} or global {{w|Nuclear warfare|nuclear war}} for instance - it could also just be a general {{w|Doomsday Clock}}). Since it seems to be Black Hat's countdown, it is safe to assume that he knows both what it counts down to and when it stops, but he just likes to mess with peoples' minds.<br />
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The fully visible part starts at 2409, and based on the pace of the scene, it seems to be in seconds. Thus, it is unclear when the eruption might occur. If the obscured digits are all 0s, it could be as soon as 40 minutes. On the other hand, if the obscured digits are '899 999', there's another 2.85 million years to go; if they are '000 001', we have a little more than 3 years.<br />
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The choice of the picture is probably also interesting. The image is distorted enough that you can imagine it as being two very different images. <br />
#It could depict a setting sun either reflecting in an ocean or with a river (possible also a lake) running out of the picture. But if it is a sun it is not very circular, although there do appear lines to indicate it is shining. This could maybe be explained with atmospheric interference.<br />
#Alternatively it depicts an exploding volcano, a mountain with lines away from it to indicate the explosion or the eruption. And then it is lava flowing away from it or collecting in lakes.<br />
In either case it makes sense, so maybe this is on purpose. If it is a volcano, the supervolcano clock makes sense. On the other hand, we are talking about the possible end of the world as we know it, and for this kind of theme a sun setting upon humanity would be a great metaphor.<br />
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The title text: "For all we know, the odds are in our favor" could imply the assumption that since we can't see the digits behind the picture, we can treat them as random. If so, chances are only 1 in 300 000 they are all zeros. However, because of statistical principles such as {{w|Benford's law}}, the digits are not entirely random, and the {{w|odds}} are higher than 1/299 999 for all the digits to be zero, since the middle 4 digits are zero. <br />
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In an alternative view, the strip is not about pondering at distributions of digits on an oracle countdown. It's more of a grim view of our natural disasters prediction capabilities. As they say – the question is not if it will happen but when it will happen. "Move the picture" would mean investing into research and warning systems - that would correspond to shifting the picture to the left. If we disregard the 40 minutes, but instead think of it as arbitrary interval of interests, minuscule as we folks have them, say - one's lifetime; or grimmer yet - some {{w|term of office}}. Because, hey, year after year passes and no apocalypse has been observed - the empirical odds are low indeed. An interesting question is what we would use the knowledge of the timing of our impending doom, if it is an event we can do nothing about, such as stopping a supervolcanic eruption or a large asteroid with direct impact course on Earth. Would we not have lives more happily for our remaining years, how few that might be, while not knowing... On the other hand, if the event is something we might prevent given enough time to plan (and the funding resources such knowledge would ensure), then it may have saved us, if we moved the picture just in time!<br />
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Using a countdown theme for comic #1159 could be a subtle joke, as 11:59/23:59 is one minute to midnight (on the Doomsday clock!)<br />
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Supervolcanos was also referenced in the title text of [[1053: Ten Thousand]] and it is the subject of in [[1611: Baking Soda and Vinegar]].<br />
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==Transcript==<br />
:[Black Hat is sitting with his laptop on a desk when Cueball, standing behind him, looks up on the wall and asks him about the large digital countdown timer with red numbers which is hanging high up on the wall. It has a white frame around the black display with the red numbers. Most of the left part of the counter is covered by a framed picture which hangs on a string attached to a nail above the counter. The picture depicts either a setting sun reflecting in an ocean, or an exploding volcano with lava flowing away from it. The picture does not block the left most part of the frame around the counter, and it is also possible to see the two left-most lines of the first digit on the countdown, so they are both turned on. This proves that the numbers goes all the way to the left end. The next five digits are covered by the picture. Then one digit is only partly covered, as only the two most left lines are not visible. From the visible lines it is though clear that this digit shows a 0. The next seven digits are fully visible, giving eight discernible digits.]<br />
:{| class="wikitable"<br />
|style="background-color:black;"| <font color="red">'''00002409'''</font><br />
|} <br />
:Cueball: What's that?<br />
:Black Hat: Countdown.<br />
:[Same picture, but Cueball is looking at Black Hat. The counter counts down.]<br />
:{| class="wikitable"<br />
|style="background-color:black;"| <font color="red">'''00002400'''</font><br />
|} <br />
:Cueball: To what?<br />
:Black Hat: Supervolcano, I think. I forget which one.<br />
:[Cueball looks up again for about 18s (between 2nd and fourth image) - beat panel.]<br />
:{| class="wikitable"<br />
|style="background-color:black;"| <font color="red">'''00002396'''</font><br />
|} <br />
<br><br />
:[Cueball looks at Black Hat again.]<br />
:{| class="wikitable"<br />
|style="background-color:black;"| <font color="red">'''00002382'''</font><br />
|} <br />
:Cueball: Maybe we should move that picture?<br />
:Black Hat: Too hard to reach. It's probably fine.<br />
<br />
{{comic discussion}}<br />
<br />
[[Category:Comics with color]]<br />
[[Category:Comics featuring Cueball]]<br />
[[Category:Comics featuring Black Hat]]<br />
[[Category:Math]]<br />
[[Category:Statistics]]<br />
[[Category:Time]]</div>
172.68.90.22
https://www.explainxkcd.com/wiki/index.php?title=Talk:2010:_Update_Notes&diff=159145
Talk:2010: Update Notes
2018-06-22T16:43:18Z
<p>172.68.90.22: Stab at Google Hangouts?</p>
<hr />
<div><!--Please sign your posts with ~~~~ and don't delete this text. New comments should be added at the bottom.--><br />
[[Special:Contributions/108.162.216.46|108.162.216.46]] 16:42, 22 June 2018 (UTC)<br />
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I feel like this might be aimed at Google Hangouts. We started using it for our business several years ago, and every year it gets HARDER to use. [[Special:Contributions/172.68.90.22|172.68.90.22]] 16:43, 22 June 2018 (UTC) SiliconWolf</div>
172.68.90.22
https://www.explainxkcd.com/wiki/index.php?title=Talk:2005:_Attention_Span&diff=158725
Talk:2005: Attention Span
2018-06-12T15:35:36Z
<p>172.68.90.22: </p>
<hr />
<div><!--Please sign your posts with ~~~~ and don't delete this text. New comments should be added at the bottom.--><br />
Do you think the book being referenced is a Dragon Lance book?[[Special:Contributions/162.158.106.24|162.158.106.24]] 04:33, 11 June 2018 (UTC)<br />
: I think with the "thicker than its wide" comment, it does sound like Dragonlance Chronicles. Also, it IS a classic [[Special:Contributions/162.158.155.104|162.158.155.104]] 07:40, 12 June 2018 (UTC)<br />
: Sounds like a Wheel of Time omnibus, if such a thing actually exists. [[Special:Contributions/108.162.216.148|108.162.216.148]] 16:29, 11 June 2018 (UTC)<br />
Or it could be one of the alternate art covers of one of the Dark Sword books, or is that too deep a cut even for Randall? [[Special:Contributions/162.158.106.24|162.158.106.24]] 22:46, 11 June 2018 (UTC)<br />
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The comic contains a hyperlink to what appears to be exactly the kind of article Cueball apparently "''just'' finished reading", or at least my mobile reader is picking up a hyperlink. I've added a small note about this; I'm not linking the article directly for personal reasons. [[Special:Contributions/108.162.221.227|108.162.221.227]] 05:51, 11 June 2018 (UTC)<br />
: I linked it. If it's linked in the original then it should be here, too. Maybe it belongs more to the trivia section, I don't know, but it definitely has to be shown here somewhere. On a side node: did Randall ever do something like that before? [[User:Elektrizikekswerk|Elektrizikekswerk]] ([[User talk:Elektrizikekswerk|talk]]) 06:53, 11 June 2018 (UTC)<br />
:: Linking other content behind the image? Yes, I think he did it several times before. The only actual comic I remember, however, is [[351: Trolling]]. --[[User:YMS|YMS]] ([[User talk:YMS|talk]]) 09:17, 11 June 2018 (UTC)<br />
:Considering that the link contains a link to this https://www.youtube.com/watch?v=jltKnDlH_OA I believe that omission is no an option [[Special:Contributions/162.158.234.58|162.158.234.58]] 09:51, 11 June 2018 (UTC)<br />
:::[[1723: Meteorite Identification]], [[1506: xkcloud]], [[1572: xkcd Survey]]... just to name a few more. [[User:Herobrine|Herobrine]] ([[User talk:Herobrine|talk]]) 09:55, 11 June 2018 (UTC)<br />
:::: Ah, very well :) The difference between those three and this one and 351 is that in the latter the link is "hidden". The others say "Click here" either directly or in alt-text. And in xkcloud it isn't an external link. Whatever. Maybe we should consider making a category of them? [[User:Elektrizikekswerk|Elektrizikekswerk]] ([[User talk:Elektrizikekswerk|talk]]) 11:04, 11 June 2018 (UTC)<br />
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I must admit to never having watch the seminal movie Surf ninjas but wikipedia tells me there is not only a novelisation, by A L Singer (Peter Lerangis) but also the screenplay. {{unsigned|Arachrah}}<br />
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I once advanced the theory that Sodor is the future of Mordor after the machines won and evolved into trains. [[Special:Contributions/162.158.62.51|162.158.62.51]] 12:46, 11 June 2018 (UTC) Jedman67<br />
: Sounds like Mieville's Railsea. [[Special:Contributions/108.162.216.148|108.162.216.148]] 16:29, 11 June 2018 (UTC)<br />
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Dragonsbane isn't nearly long enough to meet the thickness requirement --[[Special:Contributions/162.158.75.196|162.158.75.196]] 17:17, 11 June 2018 (UTC)RyanR<br />
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Does anyone feel like the punchline is misplaced? Start with claim that he has no attn span any more, then she lists various overly long works he clearly does read while he protests and defends, then he concludes with punchline "no attn span for anything good." In fact, she should probably deliver the line, after discovering what he has on his bookshelf. [[Special:Contributions/162.158.122.42|162.158.122.42]] 20:25, 11 June 2018 (UTC)<br />
:The key here was diminishing attention span with age, so he indicated "...for anything good ANYMORE." The joke is that this isn't something that changed. [[Special:Contributions/108.162.216.112|108.162.216.112]] 22:13, 11 June 2018 (UTC)<br />
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What bumps me about this comic is that the book Megan describes to make her point sounds like it would be an excellent well-structured book, very high quality reading, akin to Lord Of The Rings (Cueball even specifies it's a classic). REALLY doesn't fit with the theme of low quality crap reading this comic is going for. [[User:NiceGuy1|NiceGuy1]] ([[User talk:NiceGuy1|talk]]) 04:51, 12 June 2018 (UTC)<br />
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I've read all of the books mentioned as possible matches. And none of them have dragons holding a sword in their mouth. And since the book cover sounds EXACTLY like something I would enjoy reading, I really must insist that we demand that Randall admit which book he was referring to. [[Special:Contributions/172.68.90.22|172.68.90.22]] SiliconWolf</div>
172.68.90.22