Beta
Greek alphabet  



History  
Use in other languages  
Related topics  
Beta (UK: /ˈbiːtə/, US: /ˈbeɪtə/; uppercase Β, lowercase β, or cursive ϐ; Ancient Greek: βῆτα, romanized: bē̂ta or Greek: βήτα, romanized: víta) is the second letter of the Greek alphabet. In the system of Greek numerals, it has a value of 2. In Ancient Greek, beta represented the voiced bilabial plosive IPA: [b]. In Modern Greek, it represents the voiced labiodental fricative IPA: [v] while IPA: [b] in borrowed words is instead commonly transcribed as μπ. Letters that arose from beta include the Roman letter ⟨B⟩ and the Cyrillic letters ⟨Б⟩ and ⟨В⟩.
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 βῆτα bêta, pronounced [bɛ̂ːta] in Ancient Greek. It is spelled βήτα in modern monotonic orthography and pronounced [ˈvita].
History
The letter beta was derived from the Phoenician letter beth .
The letter Β had the largest number of highly divergent local forms. Besides the standard form (either rounded or pointed, ), there were forms as varied as (Gortyn), and (Thera), (Argos), (Melos), (Corinth), (Megara, Byzantium), and (Cyclades).^{[citation needed]}
Uses
Algebraic numerals
In the system of Greek numerals, 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; pseudoimplied) 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 be confused with standard deviation (or the semivariance, 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 marketdrawdowns, during periods of marketstress 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, Greek minuscule beta denotes a voiced bilabial fricative [β].
A superscript version may also indicate a compressed vowel, like [ɯᵝ].
Meteorology
Beta has twice been used to name an Atlantic Basin tropical cyclone:
 Hurricane Beta, in 2005
 Tropical Storm Beta, in 2020
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 or beta rays. Decays producing electrons or their antiparticles are called beta decays. In regression analysis, ⟨B⟩ symbolizes nonstandardized partial slope coefficients, whereas ⟨β⟩ represents standardized (standard deviationscore form) coefficients; in both cases, the coefficients reflect the change in the criterion Y per oneunit change in the value of the associated predictor X. β is also used in biology, for instance in βCarotene, a primary source of provitamin A, or the β cells in pancreatic islets, which produce insulin.
β is sometimes used as a placeholder for an ordinal number if α is already used. For example, the two roots of a quadratic equation are typically labelled α and β.
In spaceflight, beta angle 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 protontoelectron mass ratio.
The uppercase letter beta is not generally used as a symbol because it tends to be rendered identically to the uppercase Latin B.
Rock climbing terminology
The term "beta" 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 selfidentifier among members of manosphere communities, particularly incels, who do not believe they are assertive or traditionally masculine, and feel overlooked by women. It is also used to negatively describe other men who are not assertive, particularly in heterosexual relationships.
Statistics
In statistics, beta may represent type II error, or regression slope.
Typography
In some highquality typesetting, especially in the French tradition, a typographic variant of the lowercase letter without a descender is used within a word for ancient Greek: βίβλος is printed βίϐλος.
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. Although similarly named, they are very different in function and obsolescence.
 Betamax 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 lowercase beta. Betamax lost in the market and is an oftused example of a technically superior solution that failed due to market forces.
 Betacam, 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 television, and their scarcity today is because the industry has moved to HD formats.
Character encodings
 Greek Beta
Preview  Β  β  ϐ  ᵝ  ᵦ  

Unicode name  GREEK CAPITAL LETTER BETA  GREEK SMALL LETTER BETA  GREEK BETA SYMBOL  MODIFIER LETTER SMALL BETA  GREEK SUBSCRIPT SMALL LETTER BETA  
Encodings  decimal  hex  dec  hex  dec  hex  dec  hex  dec  hex 
Unicode  914  U+0392  946  U+03B2  976  U+03D0  7517  U+1D5D  7526  U+1D66 
UTF8  206 146  CE 92  206 178  CE B2  207 144  CF 90  225 181 157  E1 B5 9D  225 181 166  E1 B5 A6 
Numeric character reference  Β 
Β 
β 
β 
ϐ 
ϐ 
ᵝ 
ᵝ 
ᵦ 
ᵦ 
Named character reference  Β  β  
DOS Greek  129  81  153  99  
DOS Greek2  165  A5  215  D7  
Windows 1253  194  C2  226  E2  
TeX  \beta 
 Coptic Vida
Preview  Ⲃ  ⲃ  

Unicode name  COPTIC CAPITAL LETTER VIDA  COPTIC SMALL LETTER VIDA  
Encodings  decimal  hex  dec  hex 
Unicode  11394  U+2C82  11395  U+2C83 
UTF8  226 178 130  E2 B2 82  226 178 131  E2 B2 83 
Numeric character reference  Ⲃ 
Ⲃ 
ⲃ 
ⲃ 
Preview  Ꞵ  ꞵ  

Unicode name  LATIN CAPITAL LETTER BETA  LATIN SMALL LETTER BETA  
Encodings  decimal  hex  dec  hex 
Unicode  42932  U+A7B4  42933  U+A7B5 
UTF8  234 158 180  EA 9E B4  234 158 181  EA 9E B5 
Numeric character reference  Ꞵ 
Ꞵ 
ꞵ 
ꞵ 
 Mathematical Beta
Preview  𝚩  𝛃  𝛣  𝛽  𝜝  𝜷  

Unicode name  MATHEMATICAL BOLD CAPITAL BETA 
MATHEMATICAL BOLD SMALL BETA 
MATHEMATICAL ITALIC CAPITAL BETA 
MATHEMATICAL ITALIC SMALL BETA 
MATHEMATICAL BOLD ITALIC CAPITAL BETA 
MATHEMATICAL BOLD ITALIC SMALL BETA  
Encodings  decimal  hex  dec  hex  dec  hex  dec  hex  dec  hex  dec  hex 
Unicode  120489  U+1D6A9  120515  U+1D6C3  120547  U+1D6E3  120573  U+1D6FD  120605  U+1D71D  120631  U+1D737 
UTF8  240 157 154 169  F0 9D 9A A9  240 157 155 131  F0 9D 9B 83  240 157 155 163  F0 9D 9B A3  240 157 155 189  F0 9D 9B BD  240 157 156 157  F0 9D 9C 9D  240 157 156 183  F0 9D 9C B7 
UTF16  55349 57001  D835 DEA9  55349 57027  D835 DEC3  55349 57059  D835 DEE3  55349 57085  D835 DEFD  55349 57117  D835 DF1D  55349 57143  D835 DF37 
Numeric character reference  𝚩 
𝚩 
𝛃 
𝛃 
𝛣 
𝛣 
𝛽 
𝛽 
𝜝 
𝜝 
𝜷 
𝜷 
Preview  𝝗  𝝱  𝞑  𝞫  

Unicode name  MATHEMATICAL SANSSERIF BOLD CAPITAL BETA 
MATHEMATICAL SANSSERIF BOLD SMALL BETA 
MATHEMATICAL SANSSERIF BOLD ITALIC CAPITAL BETA 
MATHEMATICAL SANSSERIF BOLD ITALIC SMALL BETA  
Encodings  decimal  hex  dec  hex  dec  hex  dec  hex 
Unicode  120663  U+1D757  120689  U+1D771  120721  U+1D791  120747  U+1D7AB 
UTF8  240 157 157 151  F0 9D 9D 97  240 157 157 177  F0 9D 9D B1  240 157 158 145  F0 9D 9E 91  240 157 158 171  F0 9D 9E AB 
UTF16  55349 57175  D835 DF57  55349 57201  D835 DF71  55349 57233  D835 DF91  55349 57259  D835 DFAB 
Numeric character reference  𝝗 
𝝗 
𝝱 
𝝱 
𝞑 
𝞑 
𝞫 
𝞫 
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.