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🔗 Computer science

The man or boy test was proposed by computer scientist Donald Knuth as a means of evaluating implementations of the ALGOL 60 programming language. The aim of the test was to distinguish compilers that correctly implemented "recursion and non-local references" from those that did not.

There are quite a few ALGOL60 translators in existence which have been designed to handle recursion and non-local references properly, and I thought perhaps a little test-program may be of value. Hence I have written the following simple routine, which may separate the man-compilers from the boy-compilers.

🔗 Mathematics 🔗 Statistics

Simpson's paradox, which goes by several names, is a phenomenon in probability and statistics, in which a trend appears in several different groups of data but disappears or reverses when these groups are combined. This result is often encountered in social-science and medical-science statistics and is particularly problematic when frequency data is unduly given causal interpretations. The paradox can be resolved when causal relations are appropriately addressed in the statistical modeling.

Simpson's paradox has been used as an exemplar to illustrate to the non-specialist or public audience the kind of misleading results mis-applied statistics can generate. Martin Gardner wrote a popular account of Simpson's paradox in his March 1976 Mathematical Games column in Scientific American.

Edward H. Simpson first described this phenomenon in a technical paper in 1951, but the statisticians Karl Pearson et al., in 1899, and Udny Yule, in 1903, had mentioned similar effects earlier. The name Simpson's paradox was introduced by Colin R. Blyth in 1972.

It is also referred to as or Simpson's reversal, Yule–Simpson effect, amalgamation paradox, or reversal paradox.

🔗 Medicine 🔗 Medicine/Ophthalmology

The Purkinje effect or Purkinje phenomenon (Czech: [ˈpurkɪɲɛ] (listen); sometimes called the Purkinje shift, often incorrectly pronounced ) is the tendency for the peak luminance sensitivity of the eye to shift toward the blue end of the color spectrum at low illumination levels as part of dark adaptation. In consequence, reds will appear darker relative to other colors as light levels decrease. The effect is named after the Czech anatomist Jan Evangelista Purkyně. While the effect is often described from the perspective of the human eye, it is well established in a number of animals under the same name to describe the general shifting of spectral sensitivity due to pooling of rod and cone output signals as a part of dark/light adaptation.

This effect introduces a difference in color contrast under different levels of illumination. For instance, in bright sunlight, geranium flowers appear bright red against the dull green of their leaves, or adjacent blue flowers, but in the same scene viewed at dusk, the contrast is reversed, with the red petals appearing a dark red or black, and the leaves and blue petals appearing relatively bright.

The sensitivity to light in scotopic vision varies with wavelength, though the perception is essentially black-and-white. The Purkinje shift is the relation between the absorption maximum of rhodopsin, reaching a maximum at about 500 nanometres (2.0×10⁻⁵ in), and that of the opsins in the longer-wavelength cones that dominate in photopic vision, about 555 nanometres (2.19×10⁻⁵ in) (green).

In visual astronomy, the Purkinje shift can affect visual estimates of variable stars when using comparison stars of different colors, especially if one of the stars is red.

🔗 Television

The "rural purge" of American television networks (in particular CBS) was a series of cancellations in the early 1970s of still-popular rural-themed shows with demographically skewed audiences, the majority of which occurred at the end of the 1970–71 television season. In addition to rural-themed shows such as Mayberry R.F.D., The Beverly Hillbillies, and Green Acres, the cancellations ended several highly rated variety shows that had been on CBS since the beginning of television broadcasting. CBS saw a dramatic change in direction with the shift, moving away from shows with rural themes and toward more appeal to urban and suburban audiences.

🔗 United States 🔗 Food and drink 🔗 Food and drink/Foodservice

The Pizza Meter refers to sudden increases of pizza orders from U.S. government offices, such as the White House and The Pentagon, before large events such as the Iraqi invasion of Kuwait, the Panama Invasion, and the Grenada invasion.

On the night of August 1, 1990, the night before the Iraqi invasion of Kuwait, military personnel at The Pentagon came together to discuss issues in the Middle East. According to Frank Meeks, the owner of Washington, D.C.'s Domino's Pizza franchise of 45 restaurants, the CIA ordered a record-breaking 21 pizzas from Domino's that night. Between January 7 to January 16, 1991, the number of pizza deliveries to the Pentagon past 10 p.m reached 101, with another 55 pizzas delivered to the White House on January 16 between 10 p.m. and 2 a.m.

Meeks tied the influx of pizza orders from the Pentagon, White House, and the CIA to oncoming major announcements from the White House, publicizing his observations. Consequently, the public nicknamed the event "The Pizza Meter". Shortly after Meeks' comments were released, government offices no longer ordered from Domino's branches in Washington, opting to buy pizza at separate times or at different pizza joints.

🔗 Biography 🔗 Poetry 🔗 United Kingdom

The person from Porlock was an unwelcome visitor to Samuel Taylor Coleridge during his composition of the poem Kubla Khan in 1797. Coleridge claimed to have perceived the entire course of the poem in a dream (possibly an opium-induced haze), but was interrupted by this visitor from Porlock while in the process of writing it. Kubla Khan, only 54 lines long, was never completed. Thus "person from Porlock", "man from Porlock", or just "Porlock" are literary allusions to unwanted intruders who disrupt inspired creativity.

🔗 Extinction 🔗 Birds 🔗 Scottish Islands

The great auk (Pinguinus impennis) is a species of flightless alcid that became extinct in the mid-19th century. It was the only modern species in the genus Pinguinus. It is not closely related to the birds now known as penguins, which were discovered later by Europeans and so named by sailors because of their physical resemblance to the great auk.

It bred on rocky, remote islands with easy access to the ocean and a plentiful food supply, a rarity in nature that provided only a few breeding sites for the great auks. When not breeding, they spent their time foraging in the waters of the North Atlantic, ranging as far south as northern Spain and along the coastlines of Canada, Greenland, Iceland, the Faroe Islands, Norway, Ireland, and Great Britain.

The great auk was 75 to 85 centimetres (30 to 33 inches) tall and weighed about 5 kilograms (11 pounds), making it the largest alcid to survive into the modern era, and the second-largest member of the alcid family overall (the prehistoric Miomancalla was larger). It had a black back and a white belly. The black beak was heavy and hooked, with grooves on its surface. During summer, great auk plumage showed a white patch over each eye. During winter, the great auk lost these patches, instead developing a white band stretching between the eyes. The wings were only 15 cm (6 in) long, rendering the bird flightless. Instead, the great auk was a powerful swimmer, a trait that it used in hunting. Its favourite prey were fish, including Atlantic menhaden and capelin, and crustaceans. Although agile in the water, it was clumsy on land. Great auk pairs mated for life. They nested in extremely dense and social colonies, laying one egg on bare rock. The egg was white with variable brown marbling. Both parents participated in the incubation of the egg for around 6 weeks before the young hatched. The young left the nest site after 2–3 weeks, although the parents continued to care for it.

The great auk was an important part of many Native American cultures, both as a food source and as a symbolic item. Many Maritime Archaic people were buried with great auk bones. One burial discovered included someone covered by more than 200 great auk beaks, which are presumed to be the remnants of a cloak made of great auks' skins. Early European explorers to the Americas used the great auk as a convenient food source or as fishing bait, reducing its numbers. The bird's down was in high demand in Europe, a factor that largely eliminated the European populations by the mid-16th century. Scientists soon began to realize that the great auk was disappearing and it became the beneficiary of many early environmental laws, but this proved ineffectual.

Its growing rarity increased interest from European museums and private collectors in obtaining skins and eggs of the bird. On 3 June 1844, the last two confirmed specimens were killed on Eldey, off the coast of Iceland, ending the last known breeding attempt. Later reports of roaming individuals being seen or caught are unconfirmed. A record of one great auk in 1852 is considered by some to be the last sighting of a member of the species. The great auk is mentioned in several novels, and the scientific journal of the American Ornithological Society was named The Auk (now Ornithology) in honour of the bird until 2021.

🔗 Computing 🔗 Systems 🔗 Business 🔗 Engineering 🔗 Systems/Systems engineering

Parkinson's law of triviality is C. Northcote Parkinson's 1957 argument that members of an organization give disproportionate weight to trivial issues. Parkinson provides the example of a fictional committee whose job was to approve the plans for a nuclear power plant spending the majority of its time on discussions about relatively minor but easy-to-grasp issues, such as what materials to use for the staff bike shed, while neglecting the proposed design of the plant itself, which is far more important and a far more difficult and complex task.

The law has been applied to software development and other activities. The terms bicycle-shed effect, bike-shed effect, and bike-shedding were coined as metaphors to illuminate the law of triviality; it was popularised in the Berkeley Software Distribution community by the Danish software developer Poul-Henning Kamp in 1999 and has spread from there to the whole software industry.

🔗 Espionage 🔗 Germany 🔗 Politics 🔗 Psychology 🔗 Socialism 🔗 Germany/GDR

Zersetzung (pronounced [t͡sɛɐ̯ˈzɛt͡sʊŋ] , German for "decomposition" and "disruption") was a psychological warfare technique used by the Ministry for State Security (Stasi) to repress political opponents in East Germany during the 1970s and 1980s. Zersetzung served to combat alleged and actual dissidents through covert means, using secret methods of abusive control and psychological manipulation to prevent anti-government activities. Among the defining features of it was the widespread use of offensive counterespionage methods as a means of repression. People were commonly targeted on a pre-emptive and preventive basis, to limit or stop activities of political dissent and cultural incorrectness that they may have gone on to perform, and not on the basis of crimes they had actually committed. Zersetzung methods were designed to break down, undermine, and paralyze people behind "a facade of social normality" in a form of "silent repression".

Erich Honecker's succession to Walter Ulbricht as First Secretary of the Socialist Unity Party of Germany (SED) in May 1971 saw an evolution of "operational procedures" (Operative Vorgänge) conducted by Stasi away from the overt terror of the Ulbricht era towards what came to be known as Zersetzung ("Anwendung von Maßnahmen der Zersetzung"), which was formalized by Directive No. 1/76 on the Development and Revision of Operational Procedures in January 1976. The Stasi used operational psychology and its extensive network of between 170,000 and over 500,000 informal collaborators (inoffizielle Mitarbeiter) to launch personalized psychological attacks against targets to damage their mental health and lower chances of a "hostile action" against the state. Among the collaborators were youths as young as 14 years of age.

The use of Zersetzung is well documented due to Stasi files published after the Berlin Wall fell, with several thousands or up to 10,000 individuals estimated to have become victims, 5,000 of whom sustained irreversible damage. Special pensions for restitution have been created for Zersetzung victims.