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🔗 Mathematics 🔗 Statistics

The Akaike information criterion (AIC) is an estimator of out-of-sample prediction error and thereby relative quality of statistical models for a given set of data. Given a collection of models for the data, AIC estimates the quality of each model, relative to each of the other models. Thus, AIC provides a means for model selection.

AIC is founded on information theory. When a statistical model is used to represent the process that generated the data, the representation will almost never be exact; so some information will be lost by using the model to represent the process. AIC estimates the relative amount of information lost by a given model: the less information a model loses, the higher the quality of that model.

In estimating the amount of information lost by a model, AIC deals with the trade-off between the goodness of fit of the model and the simplicity of the model. In other words, AIC deals with both the risk of overfitting and the risk of underfitting.

The Akaike information criterion is named after the Japanese statistician Hirotugu Akaike, who formulated it. It now forms the basis of a paradigm for the foundations of statistics; as well, it is widely used for statistical inference.

🔗 Computing 🔗 Computing/Software 🔗 Computing/Computer science 🔗 Cryptography 🔗 Cryptography/Computer science 🔗 Computing/Computer Security

Post-quantum cryptography (sometimes referred to as quantum-proof, quantum-safe or quantum-resistant) refers to cryptographic algorithms (usually public-key algorithms) that are thought to be secure against an attack by a quantum computer. As of 2019, this is not true for the most popular public-key algorithms, which can be efficiently broken by a sufficiently strong quantum computer. The problem with currently popular algorithms is that their security relies on one of three hard mathematical problems: the integer factorization problem, the discrete logarithm problem or the elliptic-curve discrete logarithm problem. All of these problems can be easily solved on a sufficiently powerful quantum computer running Shor's algorithm. Even though current, publicly known, experimental quantum computers lack processing power to break any real cryptographic algorithm, many cryptographers are designing new algorithms to prepare for a time when quantum computing becomes a threat. This work has gained greater attention from academics and industry through the PQCrypto conference series since 2006 and more recently by several workshops on Quantum Safe Cryptography hosted by the European Telecommunications Standards Institute (ETSI) and the Institute for Quantum Computing.

In contrast to the threat quantum computing poses to current public-key algorithms, most current symmetric cryptographic algorithms and hash functions are considered to be relatively secure against attacks by quantum computers. While the quantum Grover's algorithm does speed up attacks against symmetric ciphers, doubling the key size can effectively block these attacks. Thus post-quantum symmetric cryptography does not need to differ significantly from current symmetric cryptography. See section on symmetric-key approach below.

🔗 Philosophy 🔗 Philosophy/Contemporary philosophy 🔗 Philosophy/Ethics

Master–slave morality (German: Herren- und Sklavenmoral) is a central theme of Friedrich Nietzsche's works, particularly in the first essay of his book, On the Genealogy of Morality. Nietzsche argued that there were two fundamental types of morality: "master morality" and "slave morality". Master morality values pride and power, while slave morality values kindness, empathy, and sympathy. Master morality judges actions as good or bad (e.g. the classical virtues of the noble man versus the vices of the rabble), unlike slave morality, which judges by a scale of good or evil intentions (e. g. Christian virtues and vices, Kantian deontology).

For Nietzsche, a morality is inseparable from the culture which values it, meaning that each culture's language, codes, practices, narratives, and institutions are informed by the struggle between these two moral structures.

🔗 Color

In computing, on the X Window System, X11 color names are represented in a simple text file, which maps certain strings to RGB color values. It was traditionally shipped with every X11 installation, hence the name, and is usually located in <X11root>/lib/X11/rgb.txt. The web colors list is descended from it but differs for certain color names.

Color names are not standardized by Xlib or the X11 protocol. The list does not show continuity either in selected color values or in color names, and some color triplets have multiple names. Despite this, graphic designers and others got used to them, making it practically impossible to introduce a different list. In earlier releases of X11 (prior to the introduction of Xcms), server implementors were encouraged to modify the RGB values in the reference color database to account for gamma correction.

As of X.Org Release 7.4 rgb.txt is no longer included in the roll up release, and the list is built directly into the server. The optional module xorg/app/rgb contains the stand-alone rgb.txt file.

The list first shipped with X10 release 3 (X10R3) on 7 June 1986, having been checked into RCS by Jim Gettys in 1985. The same list was in X11R1 on 18 September 1987. Approximately the full list as is available today shipped with X11R4 on 29 January 1989, with substantial additions by Paul Ravelling (who added colors based on Sinclair Paints samples), John C. Thomas (who added colors based on a set of 72 Crayola crayons he had on hand) and Jim Fulton (who reconciled contributions to produce the X11R4 list). The project was running DEC VT240 terminals at the time, so would have worked to that device.

In some applications multipart names are written with spaces, in others joined together, often in camel case. They are usually matched insensitive of case and the X Server source code contains spaced aliases for most entries; this article uses spaces and uppercase initials except where variants with spaces are not specified in the actual code.

🔗 Military history 🔗 Religion 🔗 Anthropology 🔗 Sociology 🔗 Archaeology 🔗 Mythology 🔗 Military history/Military culture, traditions, and heraldry

The kóryos (Proto-Indo-European: "army, people under arms" or "detachment, war party") refers to the hypothetical Proto-Indo-European brotherhood of warriors in which unmarried young males served for a number of years before their full integration to the host society, in the context of a rite of passage into manhood.

Subsequent Indo-European traditions and myths feature parallel linkages between property-less adolescent males, perceived as an age-class not yet fully integrated into the community of the married men; their service in a "police-army" sent away for a part of the year in the wild (where they hunted animals and raided foreign communities) and defending the host society during the remaining part of the year; their mystical self-identification with wolves and dogs as symbols of death, promiscuity, lawlessness, and warrior fury; and the idea of a liminality between invulnerability and death on one side, and youth and adulthood on the other side.

🔗 Middle Ages 🔗 Middle Ages/History 🔗 Celts 🔗 Writing systems 🔗 Ireland 🔗 Medieval Scotland

Ogham (Modern Irish: [ˈoː(ə)mˠ]; Middle Irish: ogum, ogom, later ogam [ˈɔɣəmˠ]) is an Early Medieval alphabet used primarily to write the early Irish language (in the "orthodox" inscriptions, 4th to 6th centuries AD), and later the Old Irish language (scholastic ogham, 6th to 9th centuries). There are roughly 400 surviving orthodox inscriptions on stone monuments throughout Ireland and western Britain, the bulk of which are in southern Munster. The largest number outside Ireland are in Pembrokeshire, Wales.

The vast majority of the inscriptions consist of personal names.

According to the High Medieval Bríatharogam, the names of various trees can be ascribed to individual letters. For this reason, ogam is sometimes known as the Celtic tree alphabet.

The etymology of the word ogam or ogham remains unclear. One possible origin is from the Irish og-úaim 'point-seam', referring to the seam made by the point of a sharp weapon.

🔗 Electronics

The 555 timer IC is an integrated circuit (chip) used in a variety of timer, delay, pulse generation, and oscillator applications. Derivatives provide two (556) or four (558) timing circuits in one package. Introduced in 1972 by Signetics, the 555 is still in widespread use due to its low price, ease of use, and stability. Numerous companies have made the original bipolar timers and similar low-power CMOS timers too. As of 2003, it was estimated that 1 billion units were manufactured every year. The 555 is the most popular integrated circuit ever manufactured.

🔗 Novels 🔗 Novels/Science fiction 🔗 Science Fiction

A Canticle for Leibowitz is a post-apocalyptic science fiction novel by American writer Walter M. Miller Jr., first published in 1959. Set in a Catholic monastery in the desert of the southwestern United States after a devastating nuclear war, the book spans thousands of years as civilization rebuilds itself. The monks of the Albertian Order of Leibowitz preserve the surviving remnants of man's scientific knowledge until the world is again ready for it.

The novel is a fixup of three short stories Miller published in The Magazine of Fantasy & Science Fiction that were inspired by the author's participation in the bombing of the monastery at the Battle of Monte Cassino during World War II. The book is considered one of the classics of science fiction and has never been out of print. Appealing to mainstream and genre critics and readers alike, it won the 1961 Hugo Award for best science fiction novel, and its themes of religion, recurrence, and church versus state have generated a significant body of scholarly research. A sequel, Saint Leibowitz and the Wild Horse Woman, was published posthumously in 1997.

🔗 France 🔗 Military history 🔗 Politics 🔗 Military history/Intelligence 🔗 Judaism 🔗 Military history/French military history 🔗 Jewish history 🔗 European history 🔗 Military history/European military history

The Dreyfus Affair (French: l'affaire Dreyfus, pronounced [lafɛːʁ dʁɛfys]) was a political scandal that divided the Third French Republic from 1894 until its resolution in 1906. "The Affair", as it is known in French, has come to symbolise modern injustice in the Francophone world, and it remains one of the most notable examples of a complex miscarriage of justice and antisemitism. The role played by the press and public opinion proved influential in the conflict.

The scandal began in December 1894 when Captain Alfred Dreyfus was convicted of treason. Dreyfus was a 35-year-old Alsatian French artillery officer of Jewish descent. He was sentenced to life imprisonment for allegedly communicating French military secrets to the German Embassy in Paris, and was imprisoned on Devil's Island in French Guiana, where he spent nearly five years.

In 1896, evidence came to light—primarily through an investigation instigated by Georges Picquart, head of counter-espionage—which identified the real culprit as a French Army major named Ferdinand Walsin Esterhazy. When high-ranking military officials suppressed the new evidence, a military court unanimously acquitted Esterhazy after a trial lasting only two days. The Army laid additional charges against Dreyfus, based on forged documents. Subsequently, Émile Zola's open letter J'Accuse…!, stoked a growing movement of support for Dreyfus, putting pressure on the government to reopen the case.

In 1899, Dreyfus was returned to France for another trial. The intense political and judicial scandal that ensued divided French society between those who supported Dreyfus (now called "Dreyfusards"), such as Sarah Bernhardt, Anatole France, Henri Poincaré and Georges Clemenceau, and those who condemned him (the anti-Dreyfusards), such as Édouard Drumont, the director and publisher of the antisemitic newspaper La Libre Parole. The new trial resulted in another conviction and a 10-year sentence, but Dreyfus was pardoned and released. In 1906, Dreyfus was exonerated and reinstated as a major in the French Army. He served during the whole of World War I, ending his service with the rank of lieutenant-colonel. He died in 1935.

The affair from 1894 to 1906 divided France into pro-republican, anticlerical, Dreyfusards and pro-Army, mostly Catholic "anti-Dreyfusards". It embittered French politics and encouraged radicalisation.

🔗 California 🔗 Technology 🔗 Politics 🔗 Objectivism 🔗 Politics/Libertarianism

"The Californian Ideology" is a 1995 essay by English media theorists Richard Barbrook and Andy Cameron of the University of Westminster. Barbrook describes it as a "critique of dotcom neoliberalism". In the essay, Barbrook and Cameron argue that the rise of networking technologies in Silicon Valley in the 1990s was linked to American neoliberalism and a paradoxical hybridization of beliefs from the political left and right in the form of hopeful technological determinism.

The original essay was published in Mute magazine in 1995 and later appeared on the nettime Internet mailing list for debate. A final version was published in Science as Culture in 1996. The critique has since been revised in several different versions and languages.

Andrew Leonard of Salon called Barbrook & Cameron's work "one of the most penetrating critiques of neo-conservative digital hypesterism yet published."