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๐Ÿ”— Berkson's Paradox

๐Ÿ”— Statistics

Berkson's paradox also known as Berkson's bias or Berkson's fallacy is a result in conditional probability and statistics which is often found to be counterintuitive, and hence a veridical paradox. It is a complicating factor arising in statistical tests of proportions. Specifically, it arises when there is an ascertainment bias inherent in a study design. The effect is related to the explaining away phenomenon in Bayesian networks, and conditioning on a collider in graphical models.

It is often described in the fields of medical statistics or biostatistics, as in the original description of the problem by Joseph Berkson.

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๐Ÿ”— 90 percent of everything is crap

๐Ÿ”— Philosophy ๐Ÿ”— Science Fiction ๐Ÿ”— Literature ๐Ÿ”— Philosophy/Epistemology

Sturgeon's revelation (as expounded by Theodore Sturgeon), referred to as Sturgeon's law, is an adage cited as "ninety percent of everything is crap." The sentence derives from quotations by Sturgeon, an American science fiction author and critic; although Sturgeon coined another adage he termed "Sturgeon's law", the "ninety percent crap" remark became Sturgeon's law.

The phrase was derived from Sturgeon's observation while science fiction was often derided for its low quality by critics, the majority of examples of works in other fields could equally be seen to be of low quality, and science fiction was thus no different in that regard from other art forms.

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๐Ÿ”— Acoustic Kitty

๐Ÿ”— United States/U.S. Government ๐Ÿ”— United States ๐Ÿ”— Espionage ๐Ÿ”— Cats

Acoustic Kitty was a CIA project launched by the Central Intelligence Agency Directorate of Science & Technology, which in the 1960s intended to use cats to spy on the Kremlin and Soviet embassies. In an hour-long procedure a veterinary surgeon implanted a microphone in the cat's ear canal, a small radio transmitter at the base of its skull and a thin wire into its fur.

This would allow the cat to innocuously record and transmit sound from its surroundings. Due to problems with distraction, the cat's sense of hunger had to be addressed in another operation. Victor Marchetti, a former CIA officer, said Project Acoustic Kitty cost about $20 million.

The first Acoustic Kitty mission was to eavesdrop on two men in a park outside the Soviet compound on Wisconsin Avenue in Washington, D.C. The cat was released nearby, but was hit and allegedly killed by a taxi almost immediately. However, this was disputed in 2013 by Robert Wallace, a former Director of the CIA's Office of Technical Service, who said that the project was abandoned due to the difficulty of training the cat to behave as required, and "the equipment was taken out of the cat; the cat was re-sewn for a second time, and lived a long and happy life afterwards". Subsequent tests also failed. Shortly thereafter the project was considered a failure and declared to be a total loss. However, other accounts report more success for the project.

The project was cancelled in 1967. A closing memorandum said that the CIA researchers believed that they could train cats to move short distances, but that "the environmental and security factors in using this technique in a real foreign situation force us to conclude that for our (intelligence) purposes, it would not be practical." The project was disclosed in 2001, when some CIA documents were declassified.

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๐Ÿ”— DRAKON โ€“ An algorithmic visual programming language

๐Ÿ”— Computing ๐Ÿ”— Spaceflight ๐Ÿ”— Computing/Software

DRAKON is an algorithmic visual programming and modeling language developed within the Buran space project following ergonomic design principles. The language provides a uniform way to represent flowcharts of any complexity that are easy to read and understand.

The DRAKON Editor, which was released in September 2011, is an implementation of the language available in the public domain. It can be used for creating documentation, or for creating visual programs that can be converted to source code in other languages.

Unlike UML's philosophy, DRAKON's language philosophy is based on being augmented if needed, by using a hybrid language, which can be illustrated as "incrustating code snippets from text language used into shape DRAKON requires". This way, DRAKON always remains a simple visual language that can be used as an augmentation for a programmer who is interested in making their own project code easier to support or other long-term needs for example improving the ergonomics of the coding process or to making code easier to review and understand.

The name DRAKON is the Russian acronym for "ะ”ั€ัƒะถะตะปัŽะฑะฝั‹ะน ะ ัƒััะบะธะน ะะปะณะพั€ะธั‚ะผะธั‡ะตัะบะธะน [ัะทั‹ะบ], ะšะพั‚ะพั€ั‹ะน ะžะฑะตัะฟะตั‡ะธะฒะฐะตั‚ ะะฐะณะปัะดะฝะพัั‚ัŒ", which translates to "Friendly Russian algorithmic [language] that illustrates (or provides clarity)". The word "ะฝะฐะณะปัะดะฝะพัั‚ัŒ" (pronounced approximately as "naa-glya-dno-st-th") refers to a concept or idea being easy to imagine and understand, and may be translated as "clarity".

The DRAKON language can be used both as a modelling/"markup" language (which is considered a standalone "pure DRAKON" program) and as a programming language (as part of a hybrid language).

Integration of a stricter, "academic", variant of a markup language into programming, such as provided by DRAKON, adds syntactic sugar allowing users of different programming languages to comprehend each other's contributions to the overall project and even provide commentary if needed.

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๐Ÿ”— Two capacitor paradox

๐Ÿ”— Electronics

The two capacitor paradox or capacitor paradox is a paradox, or counterintuitive thought experiment, in electric circuit theory. The thought experiment is usually described as follows: Two identical capacitors are connected in parallel with an open switch between them. One of the capacitors is charged with a voltage of V i {\displaystyle V_{i}} , the other is uncharged. When the switch is closed, some of the charge Q = C V i {\displaystyle Q=CV_{i}} on the first capacitor flows into the second, reducing the voltage on the first and increasing the voltage on the second. When a steady state is reached and the current goes to zero, the voltage on the two capacitors must be equal since they are connected together. Since they both have the same capacitance C {\displaystyle C} the charge will be divided equally between the capacitors so each capacitor will have a charge of Q 2 {\displaystyle {Q \over 2}} and a voltage of V f = Q 2 C = V i 2 {\displaystyle V_{f}={Q \over 2C}={V_{i} \over 2}} . At the beginning of the experiment the total initial energy W i {\displaystyle W_{i}} in the circuit is the energy stored in the charged capacitor:

W i = 1 2 C V i 2 {\displaystyle W_{i}={1 \over 2}CV_{i}^{2}} .

At the end of the experiment the final energy W f {\displaystyle W_{f}} is equal to the sum of the energy in the two capacitors

W f = 1 2 C V f 2 + 1 2 C V f 2 = C V f 2 = C ( V i 2 ) 2 = 1 4 C V i 2 = 1 2 W i {\displaystyle W_{f}={1 \over 2}CV_{f}^{2}+{1 \over 2}CV_{f}^{2}=CV_{f}^{2}=C({V_{i} \over 2})^{2}={1 \over 4}CV_{i}^{2}={1 \over 2}W_{i}}

Thus the final energy W f {\displaystyle W_{f}} is equal to half of the initial energy W i {\displaystyle W_{i}} . Where did the other half of the initial energy go?

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๐Ÿ”— Isochronous Curves

๐Ÿ”— Mathematics

A tautochrone or isochrone curve (from Greek prefixes tauto- meaning same or iso- equal, and chrono time) is the curve for which the time taken by an object sliding without friction in uniform gravity to its lowest point is independent of its starting point on the curve. The curve is a cycloid, and the time is equal to ฯ€ times the square root of the radius (of the circle which generates the cycloid) over the acceleration of gravity. The tautochrone curve is related to the brachistochrone curve, which is also a cycloid.

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๐Ÿ”— The China GPS shift problem

๐Ÿ”— China ๐Ÿ”— Maps

Due to national security concerns, the use of geographic information in the People's Republic of China is restricted to entities that obtain a special authorization from the administrative department for surveying and mapping under the State Council. Consequences of the restriction include fines for unauthorized surveys, lack of geotagging information on many cameras when the GPS chip detects a location within China, incorrect alignment of street maps with satellite maps in various applications, and seeming unlawfulness of crowdsourced mapping efforts such as OpenStreetMap.

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๐Ÿ”— Saskatoon Freezing Deaths

๐Ÿ”— Canada ๐Ÿ”— Death ๐Ÿ”— Law Enforcement ๐Ÿ”— Indigenous peoples of North America ๐Ÿ”— Canada/Saskatchewan

The Saskatoon freezing deaths were a series of deaths of Indigenous Canadians in Saskatoon, Saskatchewan, in the early 2000s, which were confirmed to have been caused by members of the Saskatoon Police Service. The police officers would arrest Indigenous people, usually men, for alleged drunkenness and/or disorderly behaviour, sometimes without cause. The officers would then drive them to the outskirts of the city at night in the winter, and abandon them, leaving them stranded in sub-zero temperatures.

The practice was known as taking Indigenous people for "starlight tours" and dates back to 1976. As of 2021, despite convictions for related offences, no Saskatoon police officer has been convicted specifically for having caused freezing deaths.

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๐Ÿ”— Women-Are-Wonderful Effect

๐Ÿ”— Psychology ๐Ÿ”— Women's History ๐Ÿ”— Discrimination ๐Ÿ”— Gender Studies ๐Ÿ”— Men's Issues

The women-are-wonderful effect is the phenomenon found in psychological and sociological research which suggests that people associate more positive attributes with women compared to men. This bias reflects an emotional bias toward women as a general case. The phrase was coined by Alice Eagly and Antonio Mladinic in 1994 after finding that both male and female participants tend to assign positive traits to women, with female participants showing a far more pronounced bias. Positive traits were assigned to men by participants of both genders, but to a far lesser degree.

The authors supposed that the positive general evaluation of women might derive from the association between women and nurturing characteristics. This bias is suggested as a form of misandry/'benevolent misogyny', the latter being a concept within the theoretical framework of ambivalent sexism.

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๐Ÿ”— --All You Zombies--

๐Ÿ”— Novels ๐Ÿ”— Novels/Science fiction ๐Ÿ”— LGBT studies ๐Ÿ”— Novels/Short story

"โ€‰'โ€”All You Zombiesโ€”'โ€‰" is a science fiction short story by American writer Robert A. Heinlein. It was written in one day, July 11, 1958, and first published in the March 1959 issue of Fantasy and Science Fiction magazine after being rejected by Playboy.

The story involves a number of paradoxes caused by time travel. In 1980, it was nominated for the Balrog Award for short fiction.

"'โ€”All You Zombiesโ€”'" further develops themes explored by the author in a previous work: "By His Bootstraps", published some 18 years earlier. Some of the same elements also appear later in The Cat Who Walks Through Walls (1985), including the Circle of Ouroboros and the Temporal Corps.

The unusual title of the story, which includes both the quotation marks and dashes shown above, is a quotation from a sentence near the end of the story; the quotation is taken from the middle of the sentence, hence the dashes indicating edited text before and after the title.

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