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Theory of the Stationary Bandit — theory of the origin of the state, developed by American scholars Martin C. McGuire and Mansur Olson.

🔗 Cognitive science 🔗 Neuroscience

Sparse distributed memory (SDM) is a mathematical model of human long-term memory introduced by Pentti Kanerva in 1988 while he was at NASA Ames Research Center. It is a generalized random-access memory (RAM) for long (e.g., 1,000 bit) binary words. These words serve as both addresses to and data for the memory. The main attribute of the memory is sensitivity to similarity, meaning that a word can be read back not only by giving the original write address but also by giving one close to it, as measured by the number of mismatched bits (i.e., the Hamming distance between memory addresses).

SDM implements transformation from logical space to physical space using distributed data representation and storage, similarly to encoding processes in human memory. A value corresponding to a logical address is stored into many physical addresses. This way of storing is robust and not deterministic. A memory cell is not addressed directly. If input data (logical addresses) are partially damaged at all, we can still get correct output data.

The theory of the memory is mathematically complete and has been verified by computer simulation. It arose from the observation that the distances between points of a high-dimensional space resemble the proximity relations between concepts in human memory. The theory is also practical in that memories based on it can be implemented with conventional RAM-memory elements.

🔗 Law 🔗 Statistics

The Howland will forgery trial was a U.S. court case in 1868 to decide Henrietta Howland Robinson's contest of the will of Sylvia Ann Howland. It is famous for the forensic use of mathematics by Benjamin Peirce as an expert witness.

🔗 Africa 🔗 Africa/Botswana

The Okavango Delta (or Okavango Grassland) (formerly spelled "Okovango" or "Okovanggo") in Botswana is a swampy inland delta formed where the Okavango River reaches a tectonic trough in the central part of the endorheic basin of the Kalahari. All the water reaching the delta is ultimately evaporated and transpired and does not flow into any sea or ocean. Each year, about 11 cubic kilometres (2.6 cu mi) of water spread over the 6,000–15,000 km² (2,300–5,800 sq mi) area. Some flood waters drain into Lake Ngami. The area was once part of Lake Makgadikgadi, an ancient lake that had mostly dried up by the early Holocene.

The Moremi Game Reserve, a National Park, is on the eastern side of the Delta. The Delta was named as one of the Seven Natural Wonders of Africa, which were officially declared on 11 February 2013 in Arusha, Tanzania. On 22 June 2014, the Okavango Delta became the 1000th site to be officially inscribed on the UNESCO World Heritage List.

🔗 United States 🔗 Companies 🔗 Taxation

Companies of the United States with untaxed profits deals with those U.S. companies whose offshore subsidiaries earn profits which are retained in foreign countries to defer paying U.S. corporate tax. The profits of United States corporations are subject to a federal corporate tax rate of 21%. In principle, the tax is payable on all profits of corporations, whether earned domestically or abroad. However, overseas subsidiaries of U.S. corporations are entitled to a tax deferral of profits on active income until repatriated to the U.S., and are regarded as untaxed. When repatriated, the corporations are entitled to a foreign tax credit for taxes (if any) paid in foreign countries.

Retaining such profits offshore may be regarded as a tax strategy. Many corporations have accumulated substantial untaxed profits offshore, especially in countries with low corporate tax rates. In recent years it has been estimated that untaxed profits range from US$1.6 to $2.1 trillion. The Wall Street Journal noted that the "[u]ntaxed foreign earnings are part of a contentious debate over U.S. fiscal policy and tax code." The profits earned abroad and retained there are subject to a foreign exchange risk, besides other financial risks.

The downside of a strategy of retaining profits offshore is that corporations may want or need to pay dividends to shareholders, or to make investments in the United States, besides other reasons. The alternative may be to borrow funds in the U.S., or access the funds retained offshore in the form of inter-company loans.

The Tax Cuts and Jobs Act of 2017 (TCJA) imposed a one time tax on these offshore profits at 8% (non-cash) and 15.5% (cash) respectively. The Act also includes a provision that taxes all foreign profits in the US in the year they are earned ending the ability of US companies to defer paying US tax on unrepatriated earnings.

🔗 Computer science 🔗 Mathematics

In error detection, the Damm algorithm is a check digit algorithm that detects all single-digit errors and all adjacent transposition errors. It was presented by H. Michael Damm in 2004.

🔗 United States 🔗 Mathematics 🔗 Education 🔗 United States/Massachusetts 🔗 Higher Education

Math 55 is a two-semester long first-year undergraduate mathematics course at Harvard University, founded by Lynn Loomis and Shlomo Sternberg. The official titles of the course are Honors Abstract Algebra (Math 55a) and Honors Real and Complex Analysis (Math 55b). Previously, the official title was Honors Advanced Calculus and Linear Algebra.

🔗 Linguistics 🔗 Linguistics/Applied Linguistics

A garden-path sentence is a grammatically correct sentence that starts in such a way that a reader's most likely interpretation will be incorrect; the reader is lured into a parse that turns out to be a dead end or yields a clearly unintended meaning. "Garden path" refers to the saying "to be led down [or up] the garden path", meaning to be deceived, tricked, or seduced. In A Dictionary of Modern English Usage, Fowler describes such sentences as unwittingly laying a "false scent".

Such a sentence leads the reader toward a seemingly familiar meaning that is actually not the one intended. It is a special type of sentence that creates a momentarily ambiguous interpretation because it contains a word or phrase that can be interpreted in multiple ways, causing the reader to begin to believe that a phrase will mean one thing when in reality it means something else. When read, the sentence seems ungrammatical, makes almost no sense, and often requires rereading so that its meaning may be fully understood after careful parsing.

🔗 United States/U.S. Government 🔗 United States 🔗 Mass surveillance 🔗 Telecommunications

The Communications Assistance for Law Enforcement Act (CALEA), also known as the "Digital Telephony Act," is a United States wiretapping law passed in 1994, during the presidency of Bill Clinton (Pub. L. No. 103-414, 108 Stat. 4279, codified at 47 USC 1001-1010).

CALEA's purpose is to enhance the ability of law enforcement agencies to conduct lawful interception of communication by requiring that telecommunications carriers and manufacturers of telecommunications equipment modify and design their equipment, facilities, and services to ensure that they have built-in capabilities for targeted surveillance, allowing federal agencies to selectively wiretap any telephone traffic; it has since been extended to cover broadband Internet and VoIP traffic. Some government agencies argue that it covers mass surveillance of communications rather than just tapping specific lines and that not all CALEA-based access requires a warrant.

The original reason for adopting CALEA was the Federal Bureau of Investigation's worry that increasing use of digital telephone exchange switches would make tapping phones at the phone company's central office harder and slower to execute, or in some cases impossible. Since the original requirement to add CALEA-compliant interfaces required phone companies to modify or replace hardware and software in their systems, U.S. Congress included funding for a limited time period to cover such network upgrades. CALEA was passed into law on October 25, 1994 and came into force on January 1, 1995.

In the years since CALEA was passed it has been greatly expanded to include all VoIP and broadband Internet traffic. From 2004 to 2007 there was a 62 percent growth in the number of wiretaps performed under CALEA – and more than 3,000 percent growth in interception of Internet data such as email.

By 2007, the FBI had spent $39 million on its Digital Collection System Network (DCSNet) system, which collects, stores, indexes, and analyzes communications data.

🔗 Africa 🔗 Africa/Ghana 🔗 Food and drink 🔗 Africa/Ivory Coast 🔗 Africa/French Africa

Child labour is a recurring issue in cocoa production. Cote d’Ivoire (also known in English as Ivory Coast) and Ghana, together produce nearly 60% of the world's cocoa each year. During the 2018/19 cocoa-growing season, research commissioned by the U.S. Department of Labor was conducted by NORC at the University of Chicago in these two countries and found that 1.48 million children are engaged in hazardous work on cocoa farms including working with sharp tools and agricultural chemicals and carrying heavy loads. That number of children is significant, representing 43 percent of all children living in agricultural households in cocoa growing areas. During the same period cocoa production in Cote d’Ivoire and Ghana increased 62 percent while the prevalence of child labour in cocoa production among all agricultural households increased 14 percentage points. Attention on this subject has focused on West Africa, which collectively supplies 69% of the world's cocoa, and Côte d'Ivoire, supplying 35%, in particular. The 2016 Global Estimates of Child Labour indicate that one-fifth of all African children are involved in child labour. Nine percent of African children are in hazardous work. It is estimated that more than 1.8 million children in West Africa are involved in growing cocoa. A 2013–14 survey commissioned by the Department of Labor and conducted by Tulane University found that an estimated 1.4 million children aged 5 years old to 11 years old worked in agriculture in cocoa-growing areas, while approximately 800,000 of them were engaged in hazardous work, including working with sharp tools and agricultural chemicals and carrying heavy loads. According to the NORC study, methodological differences between the 2018/9 survey and earlier ones, together with errors in the administration of the 2013/4 survey have made it challenging to document changes in the number of children engaged in child labour over the past five years.

A major study of the issue, published in Fortune magazine in the U.S. in March 2016, concluded that approximately 2.1 million children in West Africa "still do the dangerous and physically taxing work of harvesting cocoa". The report was doubtful as to whether the situation can be improved significantly.