Beta (, ; uppercase , lowercase , or
cursive
Cursive (also known as script, among other names) is any style of penmanship in which characters are written joined in a flowing manner, generally for the purpose of making writing faster, in contrast to block letters. It varies in functionalit ...
; grc, βῆτα, bē̂ta or ell, βήτα, víta) is the second letter of the
Greek alphabet
The Greek alphabet has been used to write the Greek language since the late 9th or early 8th century BCE. It is derived from the earlier Phoenician alphabet, and was the earliest known alphabetic script to have distinct letters for vowels as we ...
. In the system of Greek numerals, it has a value of 2. In
Modern Greek
Modern Greek (, , or , ''Kiní Neoellinikí Glóssa''), generally referred to by speakers simply as Greek (, ), refers collectively to the dialects of the Greek language spoken in the modern era, including the official standardized form of the ...
, it represents the
voiced labiodental fricative
The voiced labiodental fricative is a type of consonantal sound used in some spoken languages. The symbol in the International Phonetic Alphabet that represents this sound is , and the equivalent X-SAMPA symbol is v.
The sound is similar to vo ...
while in borrowed words is instead commonly transcribed as μπ. Letters that arose from beta include the Roman letter and the Cyrillic letters and .
Name
Like the names of most other Greek letters, the name of beta was adopted from the
acrophonic name of the corresponding letter in Phoenician, which was the common
Semitic word ''*bait'' ('house'). In Greek, the name was ''bêta'', pronounced in Ancient Greek. It is spelled βήτα in modern monotonic orthography and pronounced .
History
The letter beta was derived from the
Phoenician letter beth .
Uses
Algebraic numerals
In the system of
Greek numerals
Greek numerals, also known as Ionic, Ionian, Milesian, or Alexandrian numerals, are a system of writing numbers using the letters of the Greek alphabet. In modern Greece, they are still used for ordinal numbers and in contexts similar to tho ...
, beta has a value of 2. Such use is denoted by a number mark: Β′.
Computing
Finance
Beta is used in finance as a measure of (historical; pseudo-implied) financial asset sensitivity to the relevant benchmark index. Conditional on the benchmark index, the resulting beta value can vary considerably (S&P500 vs NASDAQ vs ETF of a specific industry).
Beta should not to be confused with standard deviation (or the semi-variance, which considers only negative returns): the preferred measure of the "riskiness" (historical volatility of returns) of a financial asset or a portfolio in isolation.
Beta can be calculated as the covariance of a financial asset (or portfolio) with its benchmark index, divided by the variance of the benchmark index.
Since the industry of finance gravitates towards return generating activities, typically the historical returns (percentage changes) are used in the calculations Beta values (among others).
There are numerous other methods a financial analyst can employ to derive Beta values if historical prices are not available.
Beta values change over time (company restructuring; industry sentiment; endo/exogenous factors). Beta values also vary, conditional on the time period used in calculating a Beta value.
Beta values can be negative, which infers the existence of financial assets which historically, tended to move in opposite directions to one another by some unit value.
It would seem these are the optimal "hedges" to offset market-draw-downs, during periods of market-stress and poor liquidity Beta values can vary dramatically, and previously low or even negative correlations converge to "1".
A beta of 1.5 implies that for every 1% change in the value of the benchmark index, the portfolio's value tends to change by 1.5%.
The greater the absolute value, the greater the implied move.
International Phonetic Alphabet
In the
International Phonetic Alphabet
The International Phonetic Alphabet (IPA) is an alphabetic system of phonetic transcription, phonetic notation based primarily on the Latin script. It was devised by the International Phonetic Association in the late 19th century as a standa ...
, Greek minuscule beta denotes a
voiced bilabial fricative
The voiced bilabial fricative is a type of consonantal sound, used in some spoken languages. The symbol in the International Phonetic Alphabet that represents this sound is , and the equivalent X-SAMPA symbol is B. The official symbol is the G ...
.
A superscript version may also indicate a
compressed vowel
In phonetics, vowel roundedness is the amount of rounding in the lips during the articulation of a vowel. It is labialization of a vowel. When a ''rounded'' vowel is pronounced, the lips form a circular opening, and ''unrounded'' vowels are pro ...
, like .
Meteorology
Beta has twice been used to
name
A name is a term used for identification by an external observer. They can identify a class or category of things, or a single thing, either uniquely, or within a given context. The entity identified by a name is called its referent. A personal ...
an Atlantic Basin
tropical cyclone
A tropical cyclone is a rapidly rotating storm system characterized by a low-pressure center, a closed low-level atmospheric circulation, strong winds, and a spiral arrangement of thunderstorms that produce heavy rain and squalls. Depend ...
:
*
Hurricane Beta
Hurricane Beta was a compact and intense tropical cyclone that impacted the southwestern Caribbean in late October 2005. Beta was the twenty-fourth tropical storm, fourteenth hurricane, and seventh and final major hurricane of the record-b ...
, in
2005
File:2005 Events Collage V2.png, From top left, clockwise: Hurricane Katrina in the Gulf of Mexico; the Funeral of Pope John Paul II is held in Vatican City; "Me at the zoo", the first video ever to be uploaded to YouTube; Eris was discovered in ...
*
Tropical Storm Beta, in
2020
2020 was heavily defined by the COVID-19 pandemic, which led to global Social impact of the COVID-19 pandemic, social and Economic impact of the COVID-19 pandemic, economic disruption, mass cancellations and postponements of events, COVID- ...
Mathematics and science
Beta is often used to denote a variable in mathematics and physics, where it often has specific meanings for certain applications. In physics a stream of unbound energetic electrons is commonly referred to as
beta radiation
A beta particle, also called beta ray or beta radiation (symbol β), is a high-energy, high-speed electron or positron emitted by the radioactive decay of an atomic nucleus during the process of beta decay. There are two forms of beta decay, β ...
or
beta rays
A beta particle, also called beta ray or beta radiation (symbol β), is a high-energy, high-speed electron or positron emitted by the radioactive decay of an atomic nucleus during the process of beta decay. There are two forms of beta decay, β ...
. Decays producing electrons or their antiparticles are called
beta decay
In nuclear physics, beta decay (β-decay) is a type of radioactive decay in which a beta particle (fast energetic electron or positron) is emitted from an atomic nucleus, transforming the original nuclide to an isobar of that nuclide. For ...
s. In
regression analysis
In statistical modeling, regression analysis is a set of statistical processes for estimating the relationships between a dependent variable (often called the 'outcome' or 'response' variable, or a 'label' in machine learning parlance) and one ...
, symbolizes nonstandardized partial slope coefficients, whereas represents
standardized (standard deviation-score form) coefficients; in both cases, the coefficients reflect the change in the criterion Y per one-unit change in the value of the associated predictor X. β is also used in biology, for instance in
β-Carotene
β-Carotene is an organic, strongly coloured red-orange pigment abundant in fungi, plants, and fruits. It is a member of the carotenes, which are terpenoids (isoprenoids), synthesized biochemically from eight isoprene units and thus having 40 ...
, a primary source of
provitamin A provitamin is a substance that may be converted within the body to a vitamin. The term previtamin is a synonym.
The term "provitamin" is used when it is desirable to label a substance with little or no vitamin activity, but which can be converted ...
A, or the
β cells
Beta cells (β-cells) are a type of cell found in pancreatic islets that synthesize and secrete insulin and amylin. Beta cells make up 50–70% of the cells in human islets. In patients with Type 1 diabetes, beta-cell mass and function are dimini ...
in
pancreatic islets
The pancreatic islets or islets of Langerhans are the regions of the pancreas that contain its endocrine (hormone-producing) cells, discovered in 1869 by German pathological anatomist Paul Langerhans. The pancreatic islets constitute 1–2% of ...
, which produce
insulin
Insulin (, from Latin ''insula'', 'island') is a peptide hormone produced by beta cells of the pancreatic islets encoded in humans by the ''INS'' gene. It is considered to be the main anabolic hormone of the body. It regulates the metabolism o ...
.
β is sometimes used as a placeholder for an
ordinal number
In set theory, an ordinal number, or ordinal, is a generalization of ordinal numerals (first, second, th, etc.) aimed to extend enumeration to infinite sets.
A finite set can be enumerated by successively labeling each element with the least n ...
if α is already used. For example, the two roots of a
quadratic equation
In algebra, a quadratic equation () is any equation that can be rearranged in standard form as
ax^2 + bx + c = 0\,,
where represents an unknown (mathematics), unknown value, and , , and represent known numbers, where . (If and then the equati ...
are typically labelled and .
In spaceflight,
beta angle
In orbital spaceflight, the beta angle (\boldsymbol) is the angle between a satellite's orbital plane around Earth and the geocentric position of the sun. The beta angle determines the percentage of time that a satellite in low Earth orbit (LEO) ...
describes the angle between the orbit plane of a spacecraft or other body and the vector from the sun.
β is sometimes used to mean the
proton-to-electron mass ratio In physics, the proton-to-electron mass ratio, ''μ'' or ''β'', is the rest mass of the proton (a baryon found in atoms) divided by that of the electron (a lepton found in atoms), a dimensionless quantity, namely:
:''μ'' =
The number in parenthe ...
.
Rock climbing terminology
The term "
beta
Beta (, ; uppercase , lowercase , or cursive ; grc, βῆτα, bē̂ta or ell, βήτα, víta) is the second letter of the Greek alphabet. In the system of Greek numerals, it has a value of 2. In Modern Greek, it represents the voiced labiod ...
" refers to advice on how to successfully complete a particular climbing route, boulder problem, or crux sequence.
Slang
''Beta male'', or simply ''beta'', is a slang term for men derived from the designation for beta animals in ethology, along with its counterpart, ''
alpha male.'' The term has been used as a pejorative self-identifier among members of
manosphere
The manosphere is a collection of websites, blogs, and online forums promoting masculinity, misogyny, and opposition to feminism. Communities within the manosphere include men's rights activists, incels (involuntary celibates), Men Going Their Ow ...
communities, particularly
incel
An incel ( , an abbreviation of "involuntary celibate") is a member of an Internet culture, online subculture of people who define themselves as unable to get a Romantic partner, romantic or sexual partner despite desiring one. Discussions in ...
s, who do not believe they are assertive or traditionally
masculine
Masculinity (also called manhood or manliness) is a set of attributes, behaviors, and roles associated with men and boys. Masculinity can be theoretically understood as socially constructed, and there is also evidence that some behaviors con ...
, and feel overlooked by women.
It is also used to negatively describe other men who are not assertive, particularly in
heterosexual
Heterosexuality is romantic attraction, sexual attraction or sexual behavior between people of the opposite sex or gender. As a sexual orientation, heterosexuality is "an enduring pattern of emotional, romantic, and/or sexual attractions" to ...
relationships.
Statistics
In statistics, beta may represent
type II error
In statistical hypothesis testing, a type I error is the mistaken rejection of an actually true null hypothesis (also known as a "false positive" finding or conclusion; example: "an innocent person is convicted"), while a type II error is the fa ...
, or
regression slope.
Typography
In some high-quality typesetting, especially in the French tradition, a typographic variant of the lowercase letter without a
descender
In typography and handwriting, a descender is the portion of a letter that extends below the baseline of a font.
For example, in the letter ''y'', the descender is the "tail", or that portion of the diagonal line which lies below the ''v'' c ...
is used within a word for
ancient Greek
Ancient Greek includes the forms of the Greek language used in ancient Greece and the ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Dark Ages (), the Archaic peri ...
: is printed .
In typesetting technical literature, it is a commonly made mistake to use the
German letter ß (a s–z or s–s ligature) as a replacement for β. The two letters resemble each other in some fonts, but they are unrelated.
Videotape formats
"Beta" can be used to refer to several consumer and professional videotape formats developed by Japan's
Sony Corporation
, commonly stylized as SONY, is a Japanese multinational conglomerate corporation headquartered in Minato, Tokyo, Japan. As a major technology company, it operates as one of the world's largest manufacturers of consumer and professional ...
. Although similarly named, they are very different in function and obsolescence.
*
Betamax
Betamax (also known as Beta, as in its logo) is a consumer-level analog recording and cassette format of magnetic tape for video, commonly known as a video cassette recorder. It was developed by Sony and was released in Japan on May 10, 1975, ...
was the name of a domestic videotape format developed in the 1970s and 1980s. It competed with the Video Home System (
VHS) format developed by the
Japanese Victor Company, to which it eventually succumbed. The Betamax format was also marketed
Betacord by (Sanyo); some cassettes were simply labeled "Beta", and the logo was a lower-case beta. Betamax lost in the market and is an oft-used example of a technically superior solution that failed due to market forces.
*
Betacam
Betacam is a family of half-inch professional videocassette products developed by Sony in 1982. In colloquial use, "Betacam" singly is often used to refer to a Betacam camcorder, a Betacam tape, a Betacam video recorder or the format itself.
All ...
, including Beta SP and DigiBeta, is a family of professional videotape formats launched in 1982 that was the de facto standard for professional video, advertising, and television production through the 2000s. The formats outlasted analog
NTSC
The first American standard for analog television broadcast was developed by National Television System Committee (NTSC)National Television System Committee (1951–1953), Report and Reports of Panel No. 11, 11-A, 12–19, with Some supplement ...
television, and their scarcity today is because the industry has moved to
HD formats.
Character encodings
* Greek Beta
*
Latin Beta
Latin beta (uppercase: Ꞵ, lowercase: ꞵ), is an additional letter of the Latin script, based the letter beta from the Greek alphabet. The letter is used in the various languages of Gabon and has been used in Ndaʼndaʼ language in Cameroon to ...
* Mathematical Beta
These characters are used only as mathematical symbols. Stylized Greek text should be encoded using the normal Greek letters, with markup and formatting to indicate text style.
References
{{DEFAULTSORT:Beta (Letter)
Greek letters
Phonetic transcription symbols