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🔗 Economics

The men's underwear index (MUI) is an economic index that can supposedly detect the beginnings of a recovery during an economic slump. The premise is that men's underwear are a necessity in normal economic times and sales remain stable. During a severe downturn, demand for these goods changes as new purchases are deferred. Hence, men's purchasing habits for underwear (and that of their spouses on their behalf) is thought to be a good indicator of discretionary spending for consumption at large especially during turnaround periods.

This indicator is noted for being followed by former Federal Reserve Chairman, Alan Greenspan.

🔗 Computer science 🔗 Mathematics

In combinatory logic for computer science, a fixed-point combinator (or fixpoint combinator),^: p.26 is a higher-order function (i.e. a function which takes a function as argument) that returns some fixed point (a value that is mapped to itself) of its argument function, if one exists.

Formally, if ${\displaystyle {\textsf {fix}}}$ is a fixed-point combinator and the function ${\displaystyle f}$ has one or more fixed points, then ${\displaystyle {\textsf {fix}}\ f}$ is one of these fixed points, i.e.

${\displaystyle f\ ({\textsf {fix}}\ f)={\textsf {fix}}\ f\ .}$

Fixed-point combinators can be defined in the lambda calculus and in functional programming languages and provide a means to allow for recursive definitions.

🔗 Photography 🔗 Photography/History of photography 🔗 Gemology and Jewelry

A stanhope or stanho-scope is an optical device that enables the viewing of microphotographs without using a microscope. They were invented by René Dagron in 1857. Dagron bypassed the need for an expensive microscope to view the microscopic photographs by attaching the microphotograph at the end of a modified Stanhope lens. He called the devices bijoux photo-microscopiques or microscopic photo-jewelry.

🔗 Environment

🔗 Apple Inc. 🔗 Computing 🔗 Computing/Software 🔗 Computing/Free and open-source software 🔗 Linux 🔗 Perl

Vim (; a contraction of Vi IMproved) is a clone, with additions, of Bill Joy's vi text editor program for Unix. Vim's author, Bram Moolenaar, based it upon the source code for a port of the Stevie editor to the Amiga and released a version to the public in 1991. Vim is designed for use both from a command-line interface and as a standalone application in a graphical user interface. Vim is free and open-source software and is released under a license that includes some charityware clauses, encouraging users who enjoy the software to consider donating to children in Uganda. The license is compatible with the GNU General Public License through a special clause allowing distribution of modified copies "under the GNU GPL version 2 or any later version".

Since its release for the Amiga, cross-platform development has made it available on many other systems. In 2006, it was voted the most popular editor amongst Linux Journal readers; in 2015 the Stack Overflow developer survey found it to be the third most popular text editor, and the fifth most popular development environment in 2019.

🔗 United States 🔗 Companies 🔗 United States/Washington - Seattle 🔗 United States/Washington 🔗 Fashion

Nordstrom, Inc. () is an American luxury department store chain founded in 1901 by John W. Nordstrom and Carl F. Wallin. It originated as a shoe store, and evolved into a full-line retailer with departments for clothing, footwear, handbags, jewelry, accessories, cosmetics, and fragrances. Some stores feature home furnishings and wedding departments, and several have in-house cafes, restaurants, and espresso bars.

As of 2020, Nordstrom operates 117 stores in 40 U.S. states, three Canadian provinces, and Puerto Rico. The corporate headquarters and flagship store are located in the former Frederick & Nelson building in Seattle, Washington; a second flagship store is located near Columbus Circle in New York City. Its subsidiaries include the off-price department store chain Nordstrom Rack and the members-only online store HauteLook.

🔗 Statistics

The Erlang distribution is a two-parameter family of continuous probability distributions with support ${\displaystyle x\in [0,\infty )}$. The two parameters are:

• a positive integer ${\displaystyle k,}$ the "shape", and
• a positive real number ${\displaystyle \lambda ,}$ the "rate". The "scale", ${\displaystyle \mu ,}$ the reciprocal of the rate, is sometimes used instead.

The Erlang distribution with shape parameter ${\displaystyle k=1}$ simplifies to the exponential distribution. It is a special case of the gamma distribution. It is the distribution of a sum of ${\displaystyle k}$ independent exponential variables with mean ${\displaystyle 1/\lambda }$ each.

The Erlang distribution was developed by A. K. Erlang to examine the number of telephone calls which might be made at the same time to the operators of the switching stations. This work on telephone traffic engineering has been expanded to consider waiting times in queueing systems in general. The distribution is also used in the field of stochastic processes.

🔗 Internet 🔗 Software 🔗 Software/Computing 🔗 Maps

Yahoo! Pipes was a web application from Yahoo! that provided a graphical user interface for building data mashups that aggregate web feeds, web pages, and other services, creating Web-based apps from various sources, and publishing those apps. The application worked by enabling users to "pipe" information from different sources and then set up rules for how that content should be modified (for example, filtering). Other than the pipe editing page, the website had a documentation page and a discussion page. The documentation page contained information about pipes including guides for the pipe editor and troubleshooting. The discussion page enabled users to discuss the pipes with other users.

🔗 Philosophy 🔗 Philosophy/Logic 🔗 Philosophy/Epistemology

The theory of belief functions, also referred to as evidence theory or Dempster–Shafer theory (DST), is a general framework for reasoning with uncertainty, with understood connections to other frameworks such as probability, possibility and imprecise probability theories. First introduced by Arthur P. Dempster in the context of statistical inference, the theory was later developed by Glenn Shafer into a general framework for modeling epistemic uncertainty—a mathematical theory of evidence. The theory allows one to combine evidence from different sources and arrive at a degree of belief (represented by a mathematical object called belief function) that takes into account all the available evidence.

In a narrow sense, the term Dempster–Shafer theory refers to the original conception of the theory by Dempster and Shafer. However, it is more common to use the term in the wider sense of the same general approach, as adapted to specific kinds of situations. In particular, many authors have proposed different rules for combining evidence, often with a view to handling conflicts in evidence better. The early contributions have also been the starting points of many important developments, including the transferable belief model and the theory of hints.

🔗 California 🔗 California/San Francisco Bay Area

The Centennial Light is the world's longest-lasting light bulb, burning since 1901, and almost never switched off. It is at 4550 East Avenue, Livermore, California, and maintained by the Livermore-Pleasanton Fire Department. Due to its longevity, the bulb has been noted by The Guinness Book of World Records, Ripley's Believe It or Not!, and General Electric.