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πŸ”— Replication Crisis

πŸ”— Medicine πŸ”— Psychology πŸ”— Sociology πŸ”— Science πŸ”— Academic Journals

The replication crisis (or replicability crisis or reproducibility crisis) is, as of 2020, an ongoing methodological crisis in which it has been found that many scientific studies are difficult or impossible to replicate or reproduce. The replication crisis affects the social sciences and medicine most severely. The crisis has long-standing roots; the phrase was coined in the early 2010s as part of a growing awareness of the problem. The replication crisis represents an important body of research in the field of metascience.

Because the reproducibility of experimental results is an essential part of the scientific method, the inability to replicate the studies of others has potentially grave consequences for many fields of science in which significant theories are grounded on unreproducible experimental work. The replication crisis has been particularly widely discussed in the field of psychology and in medicine, where a number of efforts have been made to re-investigate classic results, to determine both the reliability of the results, and, if found to be unreliable, the reasons for the failure of replication.

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πŸ”— Von Neumann Universal Constructor

πŸ”— Mathematics

John von Neumann's universal constructor is a self-replicating machine in a cellular automata (CA) environment. It was designed in the 1940s, without the use of a computer. The fundamental details of the machine were published in von Neumann's book Theory of Self-Reproducing Automata, completed in 1966 by Arthur W. Burks after von Neumann's death.

Von Neumann's goal was to specify an abstract machine which, when run, would replicate itself. In his design, the machine consists of three parts: a 'blueprint' for itself, a mechanism that can read any blueprint and construct the machine (sans blueprint) specified by that blueprint, and a 'copy machine' that can make copies of any blueprint. After the mechanism has been used to construct the machine specified by the blueprint, the copy machine is used to create a copy of that blueprint, and this copy is placed into the new machine, resulting in a working replication of the original machine. Some machines will do this backwards, copying the blueprint and then building a machine.

To define his machine in more detail, von Neumann invented the concept of a cellular automaton. The one he used consists of a two-dimensional grid of cells, each of which can be in one of 29 states at any point in time. At each timestep, each cell updates its state depending on the states of the surrounding cells at the prior timestep. The rules governing these updates are identical for all cells.

The universal constructor is a certain pattern of cell states in this cellular automaton. It contains one line of cells that serve as a 'tape', encoding a sequence of instructions that serve as a 'blueprint' for the machine. The machine reads these instructions one by one and performs the corresponding actions. The instructions direct the machine to use its 'construction arm' to build a copy of the machine, without tape, at some other location in the cell grid. The tape can't contain instructions to build an equally long tape, just as a container can't contain a container of the same size. Therefore, the machine contains a separate 'copy machine' which reads the tape and places a copy into the newly constructed machine. The resulting new machine and tape is identical to the old one, and it proceeds to replicate again.

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πŸ”— Potato Paradox

πŸ”— Mathematics

The potato paradox is a mathematical calculation that has a counter-intuitive result. The Universal Book of Mathematics states the problem as follows:

Fred brings home 100 kg of potatoes, which (being purely mathematical potatoes) consist of 99% water. He then leaves them outside overnight so that they consist of 98% water. What is their new weight? The surprising answer is 50 kg.

In Quine's classification of paradoxes, the potato paradox is a veridical paradox.

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πŸ”— Emergence

πŸ”— Biology πŸ”— Physics πŸ”— Economics πŸ”— Philosophy πŸ”— Systems πŸ”— Philosophy/Philosophy of science πŸ”— Philosophy/Epistemology

In philosophy, systems theory, science, and art, emergence occurs when an entity is observed to have properties its parts do not have on their own. These properties or behaviors emerge only when the parts interact in a wider whole. For example, smooth forward motion emerges when a bicycle and its rider interoperate, but neither part can produce the behavior on their own.

Emergence plays a central role in theories of integrative levels and of complex systems. For instance, the phenomenon of life as studied in biology is an emergent property of chemistry, and psychological phenomena emerge from the neurobiological phenomena of living things.

In philosophy, theories that emphasize emergent properties have been called emergentism. Almost all accounts of emergentism include a form of epistemic or ontological irreducibility to the lower levels.

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πŸ”— Allen Curve

πŸ”— Science

In communication theory, the Allen curve is a graphical representation that reveals the exponential drop in frequency of communication between engineers as the distance between them increases. It was discovered by Massachusetts Institute of Technology Professor Thomas J. Allen in the late 1970s.

A related and highly significant finding of Allen's was his identification of the key role of information gatekeepers. Often such interlocutors were poorly recognized by management and yet conveyed vital concepts from just the right people to just the right other people in the organization.

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πŸ”— Stochastic Parrot

πŸ”— Computer science πŸ”— Philosophy πŸ”— Philosophy/Contemporary philosophy πŸ”— Philosophy/Philosophy of mind πŸ”— Artificial Intelligence

In machine learning, "stochastic parrot" is a term coined by Emily M. Bender in the 2021 artificial intelligence research paper "On the Dangers of Stochastic Parrots: Can Language Models Be Too Big?" by Bender, Timnit Gebru, Angelina McMillan-Major, and Margaret Mitchell. The term refers to "large language models that are impressive in their ability to generate realistic-sounding language but ultimately do not truly understand the meaning of the language they are processing."

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πŸ”— Rekursiv

πŸ”— Computing πŸ”— Computing/Computer hardware

Rekursiv was a computer processor designed by David M. Harland in the mid-1980s for Linn Smart Computing in Glasgow, Scotland. It was one of the few computer architectures intended to implement object-oriented concepts directly in hardware, a form of high-level language computer architecture. The Rekursiv operated directly on objects rather than bits, nibbles, bytes and words. Virtual memory was used as a persistent object store and unusually, the processor instruction set supported recursion (hence the name).

The project originated in an initiative within the hi-fi manufacturer Linn Products to improve its manufacturing automation systems, which at the time ran on a DEC VAX minicomputer. This resulted in the design of Lingo, an object-oriented programming language derived from Smalltalk and ALGOL. Due to the poor performance of Lingo on the VAX, a subsidiary company, Linn Smart Computing Ltd., was formed to develop a new processor to efficiently run Lingo.

The Rekursiv processor consisted of four gate-array chips named Numerik (32-bit ALU), Logik (instruction sequencer), Objekt (object-oriented memory management unit) and Klock (processor clock and support logic). A small number of prototype VMEbus boards, called Hades, comprising these four chips plus 80 MB of RAM were produced. These were intended for installation in a host system such as a Sun-3 workstation.

Although the Rekursiv was never fully developed and was not a commercial success, several Hades boards were used in academic research projects in the UK. The last known copy of a Rekursiv computer ended up at the bottom of the Forth and Clyde canal in Glasgow.

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πŸ”— Solomon Shereshevsky

πŸ”— Biography πŸ”— Russia πŸ”— Russia/mass media in Russia πŸ”— Psychology πŸ”— Russia/science and education in Russia

Solomon Veniaminovich Shereshevsky (Russian: Π‘ΠΎΠ»ΠΎΠΌΠΎΠ½ Π’Π΅Π½ΠΈΠ°ΠΌΠΈΠ½ΠΎΠ²ΠΈΡ‡ Π¨Π΅Ρ€Π΅ΡˆΠ΅Π²ΡΠΊΠΈΠΉ; 1886 – 1 May 1958), also known simply as 'Π¨' ('Sh'), 'S.', or Luria's S, was a Soviet journalist and mnemonist active in the 1920s. He was the subject of Alexander Luria's case study The Mind of a Mnemonist (1968).

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πŸ”— Indian entrepreneur, industrialist, and philanthropist, Ratan Tata, dead at 86

πŸ”— Biography πŸ”— Business πŸ”— New York (state) πŸ”— India πŸ”— New York (state)/Cornell University πŸ”— Zoroastrianism πŸ”— India/Mumbai πŸ”— India/Maharashtra

Ratan Tata (28 December 1937 – 9 October 2024) was an Indian industrialist and philanthropist who served as chairman of Tata Group and Tata Sons from 1990 to 2012, and then as interim chairman from October 2016 through February 2017. In 2008, he received the Padma Vibhushan, the second highest civilian honour in India. Ratan had previously received the Padma Bhushan, the third highest civilian honour, in 2000. He passed away on October 9, 2024, following a prolonged illness related to his age.

Ratan Tata was the son of Naval Tata, who was adopted by Ratanji Tata. Ratanji Tata was the son of Jamshedji Tata, the founder of the Tata Group. He graduated from the Cornell University College of Architecture with a bachelor's degree in architecture. He joined Tata in 1961, where he worked on the shop floor of Tata Steel. He later succeeded J. R. D. Tata as chairman of Tata Sons upon the latter's retirement in 1991. During his tenure, the Tata Group acquired Tetley, Jaguar Land Rover, and Corus, in an attempt to turn Tata from a largely India-centric group into a global business. Tata was also a philanthropist.

Tata was a prolific investor and invested in over 30 start-ups, most in a personal capacity and some via his investment company.