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🔗 Computer science 🔗 Statistics 🔗 Databases

In data mining and statistics, hierarchical clustering (also called hierarchical cluster analysis or HCA) is a method of cluster analysis that seeks to build a hierarchy of clusters. Strategies for hierarchical clustering generally fall into two categories:

• Agglomerative: This is a "bottom-up" approach: Each observation starts in its own cluster, and pairs of clusters are merged as one moves up the hierarchy.
• Divisive: This is a "top-down" approach: All observations start in one cluster, and splits are performed recursively as one moves down the hierarchy.

In general, the merges and splits are determined in a greedy manner. The results of hierarchical clustering are usually presented in a dendrogram.

Hierarchical clustering has the distinct advantage that any valid measure of distance can be used. In fact, the observations themselves are not required: all that is used is a matrix of distances. On the other hand, except for the special case of single-linkage distance, none of the algorithms (except exhaustive search in ${\displaystyle {\mathcal {O}}(2^{n})}$) can be guaranteed to find the optimum solution.

🔗 Anthropology 🔗 Palaeontology 🔗 Extinction 🔗 Indonesia 🔗 Archaeology 🔗 Mammals 🔗 Evolutionary biology 🔗 Human Genetic History 🔗 Primates 🔗 Southeast Asia

Homo floresiensis ("Flores Man"; nicknamed "hobbit") is a pygmy archaic human which inhabited the island of Flores, Indonesia, until the arrival of modern humans about 50,000 years ago.

The remains of an individual who would have stood about 1.1 m (3 ft 7 in) in height were discovered in 2003 at Liang Bua on the island of Flores in Indonesia. Partial skeletons of nine individuals have been recovered, including one complete skull, referred to as "LB1". These remains have been the subject of intense research to determine whether they represent a species distinct from modern humans; the dominant consensus is that these remains do represent a distinct species due to genetic and anatomical differences.

This hominin had originally been considered remarkable for its survival until relatively recent times, only 12,000 years ago. However, more extensive stratigraphic and chronological work has pushed the dating of the most recent evidence of its existence back to 50,000 years ago. The Homo floresiensis skeletal material is now dated from 60,000 to 100,000 years ago; stone tools recovered alongside the skeletal remains were from archaeological horizons ranging from 50,000 to 190,000 years ago.

🔗 Germany

Rinderkennzeichnungs- und Rindfleischetikettierungsüberwachungsaufgabenübertragungsgesetz listen  (RkReÜAÜG) (literally, Cattle marking and beef labeling supervision duties delegation law) was a law of the German state of Mecklenburg-Vorpommern of 1999, repealed in 2013. It dealt with the supervision of the labeling of beef.

The name is an example of the virtually unlimited compounding of nouns that is possible in many Germanic languages. German orthography uses "closed" compounds, concatenating nouns to form one long word. This is unlike most English compounds, which are separated using spaces or hyphens.

Strictly speaking, it is made up of two words, because a hyphen at the end of a word is used to show that the word will end in the same way as the following. Consequently, the two words would be Rinderkennzeichnungsüberwachungsaufgabenübertragungsgesetz and Rindfleischetikettierungsüberwachungsaufgabenübertragungsgesetz.

This is the official short title of the law; its full name is Gesetz zur Übertragung der Aufgaben für die Überwachung der Rinderkennzeichnung und Rindfleischetikettierung, corresponding to Law on delegation of duties for supervision of cattle marking and beef labeling. Most German laws have a short title consisting of a composite noun.

Words as long as this are not at all common in German. When the law was proposed in the state parliament, the members reacted with laughter and the responsible minister Till Backhaus apologized for the "possibly excessive length". In 1999, the German Language Society nominated Rindfleischetikettierungsüberwachungsaufgabenübertragungsgesetz for its Word of the Year award, but it lost to das Millennium, a Latin word that gained in usage at that time, complementing the German word for millennium, Jahrtausend.

In 2003, a decree was established that modified some real estate-related regulations; its name was longer than the above law: Grundstücksverkehrsgenehmigungszuständigkeitsübertragungsverordnung (long title: Verordnung zur Übertragung der Zuständigkeiten des Oberfinanzpräsidenten der Oberfinanzdirektion Berlin nach § 8 Satz 2 der Grundstücksverkehrsordnung auf das Bundesamt zur Regelung offener Vermögensfragen, GrundVZÜV), roughly Regulation on the delegation of authority concerning land conveyance permissions. At 67 letters, it surpassed the RkReÜAÜG, but was repealed in 2007.

🔗 Food and drink 🔗 Food and drink/Foodservice

An automat is a fast food restaurant where simple foods and drink are served by vending machines. The world's first automat was named Quisisana, which opened in Berlin, Germany in 1895.

🔗 Insects

An insect hotel, also known as a bug hotel or insect house, is a manmade structure created to provide shelter for insects. They can come in a variety of shapes and sizes depending on the specific purpose or specific insect it is catered to. Most consist of several different sections that provide insects with nesting facilities – particularly during winter, offering shelter or refuge for many types of insects. Their purposes include hosting pollinators.

🔗 Computer science

Bead sort, also called gravity sort, is a natural sorting algorithm, developed by Joshua J. Arulanandham, Cristian S. Calude and Michael J. Dinneen in 2002, and published in The Bulletin of the European Association for Theoretical Computer Science. Both digital and analog hardware implementations of bead sort can achieve a sorting time of O(n); however, the implementation of this algorithm tends to be significantly slower in software and can only be used to sort lists of positive integers. Also, it would seem that even in the best case, the algorithm requires O(n²) space.

The Cybiko is a Russian handheld computer introduced in the United States by David Yang's company Cybiko Inc. as a retail test market in New York on April 2000, and rolled out nationwide in May 2000. It is designed for teens, featuring its own two-way radio text messaging system. It had over 430 "official" freeware games and applications. Because of the text messaging system, it features a rubber QWERTY keyboard. An MP3 player add-on with a SmartMedia card slot was made for the unit as well. The company stopped manufacturing the units after two product versions and only a few years on the market. Cybikos can communicate with each other up to a maximum range of 100 metres (300 feet). Several Cybikos can chat with each other in a wireless chatroom. By the end of 2000, the Cybiko Classic sold over 500,000 units.

🔗 Science Fiction 🔗 Robotics 🔗 Theatre 🔗 Czech Republic

R.U.R. is a 1920 science-fiction play by the Czech writer Karel Čapek. "R.U.R." stands for Rossumovi Univerzální Roboti (Rossum's Universal Robots, a phrase that has been used as a subtitle in English versions). The play had its world premiere on 2 January 1921 in Hradec Králové; it introduced the word "robot" to the English language and to science fiction as a whole. R.U.R. soon became influential after its publication. By 1923 it had been translated into thirty languages. R.U.R. was successful in its time in Europe and North America. Čapek later took a different approach to the same theme in his 1936 novel War with the Newts, in which non-humans become a servant-class in human society.

🔗 Economics 🔗 Law

"The Nature of the Firm" (1937) is an article by Ronald Coase. It offered an economic explanation of why individuals choose to form partnerships, companies and other business entities rather than trading bilaterally through contracts on a market. The author was awarded the Nobel Memorial Prize in Economic Sciences in 1991 in part due to this paper. Despite the honor, the paper was written when Coase was an undergraduate and he described it later in life as "little more than an undergraduate essay."

The article argues that firms emerge because they are better equipped to deal with the transaction costs inherent in production and exchange than individuals are. Economists such as Oliver Williamson, Douglass North, Oliver Hart, Bengt Holmström, Arman Alchian and Harold Demsetz expanded on Coase's work on firms, transaction costs and contracts. Economists and political scientists have used insights from Coase's work to explain the functioning of organizations in general, not just firms. Coase's work strongly influenced the New Economics of Organization (New Institutional Economics).

Coase's article distinguished between markets as a coordination mechanism and firms as a coordination mechanism.

A crinkle crankle wall, also known as a crinkum crankum, serpentine, ribbon or wavy wall, is an unusual type of garden wall built in a serpentine pattern with alternating curves.

The crinkle crankle wall economizes on bricks, despite its sinuous configuration, because it can be made just one brick thin. If a wall this thin were to be made in a straight line, without buttresses, it would easily topple over. The alternate convex and concave curves in the wall provide stability and help it to resist lateral forces.

"Crinkle crankle" is an ablaut reduplication, defined as something with bends and turns, first attested in 1598 (though "crinkle" and "crankle" have somewhat longer histories). However, it was not until the 18th century that the term began to be applied to wavy walls. At that time these garden walls were usually aligned east-west, so that one side faced south to catch the warming sun and were historically used for growing fruit.

Many crinkle crankle walls are found in the East Anglia region of England where the marshes of The Fens were drained by Dutch engineers starting in the mid-1600s. The walls' construction is attributed to these engineers who called them slangenmuur, meaning snake wall.  The county of Suffolk claims at least 50 examples, twice as many as in the whole of the rest of the country, and where crinkle crankle is said to derive from a local dialect. In the estate village of Easton the noted crinkle crankle wall running from the former manor house to All Saints' Church is supposed to be the longest existing example. In Lymington, Hampshire, there are at least two examples of crinkle crankle walls. The oldest is thought to have been constructed at the time of the Napoleonic Wars (1803–1815) by exiled Hanoverian soldiers living in the adjacent house.

As a minor part of a larger system of fortification, such a wall may have been used to force oncoming troops to break ranks from closed to open ranks, and further expose them to defensive assault.

Thomas Jefferson (1743–1826) incorporated so-called serpentine walls into the architecture of the University of Virginia, which he founded. Flanking both sides of its landmark rotunda and extending down the length of the lawn are ten pavilions, each with its own walled garden separated by crinkle crankle walls. Although some authorities claim Jefferson invented this design, he was merely adapting a well-established English style of construction. A university document in his own hand shows how he calculated the savings and combined aesthetics with utility.