GA
A genetic algorithm (GA) is a stochastic optimization technique modeled on the principles of natural selection and genetics, employing mechanisms such as selection, crossover, and mutation to evolve a population of candidate solutions toward improved fitness for complex search and optimization problems.[1][2] GAs operate on encoded representations of solutions, typically as strings or chromosomes, evaluating their performance via a fitness function that guides iterative improvement without relying on gradient information, making them suitable for non-differentiable or multimodal landscapes.[3][4] Developed primarily by John Holland in the 1960s and formalized in his 1975 book Adaptation in Natural and Artificial Systems, GAs emerged as part of the broader field of evolutionary computation, drawing from Darwinian evolution to address adaptive systems in artificial environments.[5] Key components include an initial random population, probabilistic selection favoring high-fitness individuals, genetic operators to generate offspring, and replacement strategies to maintain diversity, often converging on near-optimal solutions for problems like function optimization, scheduling, and design.[6][7] Empirical applications have demonstrated effectiveness in engineering tasks, such as antenna design and neural network training, though performance varies by problem structure and parameter tuning.[8] While praised for handling high-dimensional spaces where traditional methods falter, GAs face criticism for sensitivity to hyperparameters, potential premature convergence, and computational expense compared to alternatives like gradient descent or particle swarm optimization; additionally, their biological analogy has sparked debate over whether they validate evolutionary theory, as real-world implementations often use simplified, non-realistic mutation rates and genome sizes that diverge from observed natural processes.[5] Despite these limitations, ongoing research integrates GAs with machine learning hybrids, enhancing robustness in areas like robotics and bioinformatics.Places
United States
The two-letter code GA serves as the official postal abbreviation for the state of Georgia, as standardized by the United States Postal Service for mail addressing and data processing.[9][10] This designation is widely used in federal, state, and commercial contexts, including vehicle license plates, official state documents, and geographic identifiers in databases. Georgia occupies 57,783 square miles in the southeastern United States, bordering the Atlantic Ocean along 100 miles of coastline and sharing land boundaries with Florida (south), Alabama (west), Tennessee and North Carolina (north), and South Carolina (east).[11] The state ranks as the eighth-most populous in the nation, with an estimated 11,029,227 residents as of July 1, 2023, according to U.S. Census Bureau data; this reflects steady growth driven by migration to urban centers like Atlanta, the state capital and largest city. Economically, Georgia contributes significantly to national output, recording a gross domestic product of $701.1 billion in 2024, bolstered by strengths in logistics (via Hartsfield-Jackson Atlanta International Airport, the world's busiest by passenger traffic), manufacturing, agriculture (notably peanuts and pecans), and emerging technology sectors.[12] Administrative uses of GA extend to state agencies, such as the Georgia Department of Transportation (GDOT) and the Georgia Environmental Protection Division (EPD), which incorporate the code in official nomenclature and operations.[11] The state, governed by Republican Brian Kemp since January 14, 2019, maintains a bicameral legislature in Atlanta and operates under a constitution ratified in 1983, emphasizing its role as a key southeastern hub for trade and governance.Africa
The Ga-Adangbe, also known as Ga-Dangme or Ga-Adangbe, form an ethnic group primarily inhabiting the coastal plains of southern Ghana, centered in the Greater Accra Region, with smaller communities extending into Togo and Benin.[13] This group includes the Ga to the west of Accra and the Adangbe (or Dangme) to the east, occupying key urban and peri-urban areas along the Gulf of Guinea.[14] The core Ga settlements comprise six historically independent coastal towns—Accra, Osu, Labadi (La), Teshie (Teshi), Nungua, and Tema—each traditionally governed by a stool symbolizing chiefly authority and communal leadership.[15] These locations form the demographic and cultural heartland of the Ga people, who migrated southward across the Volta River during the 17th century, establishing polities focused on fishing, trade, and agriculture in the Accra Plains.[16] Greater Accra, as Ghana's smallest but most densely populated region, encompasses these towns within districts such as Accra Metropolitan, Ga East, Ga West, and Tema Metropolitan, supporting over 5 million residents as of recent censuses, with Ga-Adangbe forming a significant portion.[17] In Togo, Ga-Amina subgroups reside in southern border areas near the Ghanaian frontier, numbering in the tens of thousands, while Benin's Ga communities are marginal and integrated into broader coastal ethnic mosaics.[13] No other major African geographic designations tied to "GA" beyond these Ga-Adangbe-associated locales have been verifiably documented.[18]Other geographic locations
In the ISO 3166-2 standard for country subdivisions, GA serves as the code for Goa, a state on the southwestern coast of India.[19] Goa spans 3,702 square kilometers, bordering Maharashtra to the north and Karnataka to the east and south, with a 104-kilometer coastline along the Arabian Sea. Its capital, Panaji, and largest city, Vasco da Gama, reflect its historical role as a major Portuguese enclave from 1510 until its annexation by India on December 19, 1961, following military action. Goa's geography features a mix of coastal plains, plateaus, and the Western Ghats, supporting tourism, mining, and agriculture, with rice, cashew, and coconut as key crops. As of the 2011 census, its population was 1,458,545, with projections estimating around 1.6 million by 2025, driven by migration and economic growth in hospitality and pharmaceuticals. The state's unique blend of Indian and Portuguese cultural influences, including Konkani as the official language alongside English and Marathi, underscores its distinct identity within India. No other major geographic entities outside the United States and Africa prominently use GA in official coding systems, though minor locales like Ga villages in Asia exist without standardized GA designation.[20]Organizations and institutions
Businesses and companies
General Atomics (GA) is a privately held American company specializing in defense technologies, energy systems, and advanced research. Founded in 1955 as a division of General Dynamics and acquired by the Blue family in 1986, it is headquartered in San Diego, California, and develops products such as unmanned aerial systems, electromagnetic systems, and nuclear fusion technologies for government and commercial clients.[21] General Assembly (GA) operates as a for-profit provider of immersive tech education programs, including bootcamps in software engineering, data science, UX design, and digital marketing. Established in 2011 and based in New York City, the company partners with corporations and individuals for skill-building, reporting over 100,000 alumni placements in tech roles as of recent data.[22][23] GA technologies Co., Ltd. is a Japanese real estate technology firm offering platforms for property brokerage, investment management, and renovation services under brands like RENOSY. Incorporated on March 12, 2013, and headquartered in Tokyo, it listed on the Tokyo Stock Exchange in 2018 and reported consolidated revenue of approximately 45 billion yen for the fiscal year ending December 2023.[24][25][26] General Atlantic (GA) functions as a growth equity investment firm, deploying capital in technology, healthcare, consumer, and financial services sectors worldwide. Founded in 1980 and headquartered in New York, it manages over $84 billion in assets under management as of 2023 and has backed more than 830 companies, including exits via IPOs and acquisitions.[27][28]Non-profits and associations
Gamblers Anonymous (GA) is an international mutual-aid fellowship established in January 1957 following a meeting between two individuals struggling with compulsive gambling, one of whom drew from his prior experience in Alcoholics Anonymous to initiate the group.[29] The organization adapts Alcoholics Anonymous's 12-step program, emphasizing spiritual principles, personal accountability, and peer support to foster recovery from gambling addiction through regular meetings where members share experiences, strengths, and hopes without dues or formal entry requirements.[30] GA operates autonomously via local groups worldwide, providing a structured framework that has sustained operations for over six decades, with attendance serving as a primary metric of engagement in recovery efforts.[31] The Graphic Arts Education and Research Foundation (GAERF), a non-profit entity, funds scholarships, educational programs, and research initiatives to advance skills and innovation in the printing and graphic arts industries, having supported student training and technical studies since its inception.[32]Governmental and international bodies
The United Nations General Assembly (UNGA or GA) is one of the six principal organs of the United Nations, established under Chapter IV of the UN Charter signed on June 26, 1945, and effective October 24, 1945. It consists of all 193 UN member states, with each state holding one vote regardless of size or population. The GA functions as the primary forum for multilateral discussion, adopting non-binding resolutions on global issues including peace, development, and human rights.[33][34] Decisions in the GA on procedural matters and ordinary substantive questions are made by a simple majority of members present and voting, while important matters—such as recommendations on maintaining international peace and security, electing non-permanent Security Council members, admitting new UN members, budget approval, or suspending member rights—require a two-thirds majority of members present and voting. Regular sessions convene annually starting in September, with the president elected by acclamation or secret ballot for a one-year term; special sessions can be called by the Security Council or a majority of members, and emergency special sessions under the "Uniting for Peace" mechanism address urgent threats to peace.[33] At the national level, several legislative bodies are designated as General Assemblies and abbreviated GA, particularly in bicameral systems. The Georgia General Assembly, the legislature of the U.S. state of Georgia since its 1777 constitution, comprises 180 House members and 56 senators, meeting annually from the second Monday in January through late March or April to pass laws, approve budgets, and confirm appointments. Similarly, the Virginia General Assembly, dating to 1619 as the oldest continuous legislative body in the Western Hemisphere, includes a 100-member House of Delegates and 40-member Senate, convening biennially in odd-numbered years for 45-60 days to legislate on state matters. The New Jersey General Assembly serves as the lower house of that state's bicameral legislature, with 80 members elected for two-year terms, focusing on originating revenue bills and debating policy. These bodies exemplify how "GA" denotes deliberative assemblies with defined session schedules, voting quorums, and lawmaking powers under respective constitutions.[35]Languages and linguistics
Natural languages
The Ga language (ISO 639-3: gaa), natively known as Gã, is a Kwa language within the Niger-Congo phylum, spoken primarily by the Ga ethnic group in southeastern Ghana, especially the Greater Accra Region around Accra.[36] It forms the Ga-Adangme subgroup alongside Adangme (Dangme), characterized by shared phonological and lexical features such as nasal vowels and verb serialization, diverging from other Kwa languages like Akan or Ewe through distinct consonant inventories and tonal systems.[37] Ga serves as a vernacular for daily communication among its speakers, with official status limited despite its role in local education and media in Ghana, where English predominates nationally.[36] Ethnographic and linguistic surveys estimate approximately 745,000 first-language speakers as of the mid-2010s, concentrated in urban Accra and surrounding coastal areas, though bilingualism with Akan (Twi) and English reduces monolingual use among younger generations.[38] This figure aligns with proportional data from Ghana's 2010 population and housing census, where Ga-Dangme ethnic groups comprised about 7.4% of the national population of roughly 30.8 million, implying a core speaker base under 1 million when accounting for language shift and urbanization.[39] Recent analyses indicate stable but not growing vitality, with L2 speakers potentially adding several hundred thousand in multilingual Accra contexts, though no comprehensive 2021 census update isolates Ga proficiency precisely.[36] Grammatically, Ga employs a subject-verb-object (SVO) constituent order, typical of many Kwa languages, with agglutinative elements in verb morphology.[37] It is tonal, distinguishing meaning via high and low tones on syllables (e.g., bá 'child' vs. bà 'go'), and features bound subject pronoun clitics prefixed to verbs (e.g., me-dɔ 'I eat'), contrasted with free-standing object pronouns.[40] Nouns lack grammatical gender but mark plurality through suffixes like -ŋmɛ́ or partial reduplication (e.g., abé 'person' to abéabé 'people'), while possession relies on juxtaposition or genitive markers. Verbs indicate tense-aspect via preverbal auxiliaries and particles (e.g., kɛ́ for progressive), supporting serial verb constructions for complex actions (e.g., e tsui lɛ dɔ 'he took it and ate'). Adjectives follow nouns and agree minimally in number.[37] Lexically, Ga vocabulary reflects Niger-Congo origins with substrate influences from historical interactions, including Portuguese loanwords from 15th-century trade (e.g., saasá 'sauce' from salsa) and modern English calques in urban speech. Core terms include atsɔ 'person', dɔ 'eat', tsi 'water', and ŋwɛ 'house', often compounded for specificity (e.g., tsi-mɔ 'river').[40] The language uses a Latin-based orthography standardized since the 1960s, facilitating basic literacy but challenged by dialectal tone variation in writing.[37]Dialects and accents
In linguistics, General American (GA) refers to a rhotic variety of American English characterized by the consistent pronunciation of the /r/ sound after vowels, distinguishing it from non-rhotic accents such as those historically found in parts of the Northeast or Received Pronunciation in British English.[41] This accent lacks pronounced regional markers, making it a perceived standard for broadcast media and education, though it encompasses a range of subtle variations rather than a uniform dialect.[42] GA is particularly prevalent in the Midwestern United States, including states like Minnesota, Wisconsin, and Iowa, where sociolinguistic surveys indicate it aligns closely with neutral, supra-regional norms spoken by approximately two-thirds of Americans as of the late 20th century, though exact prevalence has shifted with migration and media influence.[43] A key phonetic feature in many GA realizations is the cot–caught merger, a low-back vowel merger where the open back vowels /ɑ/ (as in "cot") and /ɔ/ (as in "caught") neutralize to [ɑ], observed in acoustic analyses of Midwestern and Western speakers but absent in some Eastern non-merged dialects.[44] This merger, documented in over 60% of U.S. dialects per phonological mapping, reflects ongoing sound changes rather than a fixed GA trait.[45] Separately, ga denotes the ISO 639-1 code for Gaeilge (Irish), a Celtic language with three traditional dialects—Ulster (Gaeilge Uladh), Connacht (Gaeilge Chonnacht), and Munster (Gaeilge Mumhan)—differentiated by phonetic shifts, such as slender vs. broad consonant realizations and lexical variations (e.g., "potato" as práta in Connacht but páta in Ulster).[46] Ulster Irish features nasalization and Scottish Gaelic influences due to historical proximity, while Munster preserves older lenition patterns, as evidenced in corpus studies of Gaeltacht speech communities; these dialects maintain mutual intelligibility but inform regional accents in Irish English substrates.[47] Unlike GA's supra-regional status, Gaeilge dialects are tied to specific Gaeltacht areas, with declining native speakers prompting standardization efforts since the 1950s Irish Orthographic Reform.[48]Scripts and characters
In abugidas derived from the ancient Brahmi script, such as Devanagari, the letter Ga (ग; Unicode U+0917) represents the consonant sound /g/, the voiced velar plosive, and serves as the third consonant in the standard ordering of these writing systems. This grapheme traces its origins to the early Brahmi letter for ga, used in inscriptions from the 3rd century BCE onward, and appears consistently across modern Indic scripts including Bengali (গ; U+0997), Gujarati (ગ; U+0997 equivalent in block), and Odia (ଗ; U+0B17). Similar Ga letters exist in other non-Latin scripts influenced by Indic traditions. In Gurmukhi, used for Punjabi, Ga is encoded as U+0A17 (ਗ).[49] Tibetan script employs U+0F42 (ག) for Ga, integral to its consonant-vowel structure. Mongolian script features U+182D (ᠭ) as the letter Ga, adapted for vertical writing and historically derived from Uyghur influences via Brahmi lineages. Southeast Asian scripts like Javanese (ꦒ; U+A992) and Buginese (ᨁ; U+1A01) also include dedicated Ga characters for the /g/ sound, reflecting regional adaptations of abugida principles. In East Asian syllabaries, Japanese Hiragana uses が (U+304C) for the mora "ga," combining the base ka with a dakuten mark for voicing, while Katakana employs ガ (U+30AC) in the same manner for emphasis or foreign words.[50] These characters, standardized in Unicode since version 1.1 (1993) for Hiragana, facilitate digital representation across diverse linguistic contexts without altering core phonetic values.Science and technology
Chemistry and materials
Gallium is a chemical element with the symbol Ga and atomic number 31, positioned in group 13 (boron group) and period 4 of the periodic table.[51][52] Classified as a post-transition metal, it appears as a soft, silvery-white solid at standard room temperature but melts into a liquid at slightly elevated temperatures due to its unusually low melting point.[51][53] The element was discovered in 1875 by French chemist Paul-Émile Lecoq de Boisbaudran, who identified it spectroscopically through new violet emission lines in samples extracted from zinc blende ore, confirming its isolation via electrolysis later that year.[51][54] This discovery validated predictions by Dmitri Mendeleev for eka-aluminum in his periodic table.[53] Key physical properties include a melting point of 29.7646 °C, boiling point of 2229 °C, and density of 5.91 g/cm³ at room temperature, rendering it denser than many liquids yet highly malleable and ductile in solid form.[51] Chemically, gallium predominantly exhibits a +3 oxidation state, reacting with acids to form salts like gallium chloride (GaCl₃) and with alkalis to produce gallates, though it resists attack by water and oxygen under ambient conditions.[51][53] Its electron configuration ([Ar] 3d¹⁰ 4s² 4p¹) contributes to semiconductor behavior in compounds.[51] In materials science, gallium's primary industrial role involves III-V compound semiconductors, such as gallium arsenide (GaAs), valued for its direct bandgap (1.42 eV) enabling efficient light emission and high electron mobility (8500 cm²/V·s) in high-frequency devices like microwave integrated circuits and solar cells.[51][55] Gallium nitride (GaN), with a wider bandgap (3.4 eV), supports high-power applications including radio-frequency amplifiers and power electronics, where it handles voltages up to 3.3 kV and operates at frequencies exceeding 10 GHz.[56][57] Elemental gallium also alloys with indium and tin to form low-melting eutectics like galinstan (melting at -19 °C), used in thermal management and flexible electronics due to non-toxicity relative to mercury.[51] Emerging materials like β-gallium oxide (β-Ga₂O₃) leverage ultrawide bandgaps (4.8 eV) and high breakdown fields (8 MV/cm) for next-generation power semiconductors, potentially reducing energy losses in converters by 50% compared to silicon carbide.[58][59] Global production, primarily from bauxite residues and zinc processing, reached approximately 500 metric tons in 2021, with over 95% directed toward electronics.[60]Biology and medicine
Geographic atrophy (GA) represents the advanced stage of dry age-related macular degeneration (AMD), characterized by well-demarcated atrophic lesions primarily affecting the outer retina, retinal pigment epithelium (RPE), choriocapillaris, and photoreceptor cells in the macula, leading to irreversible central vision loss.[61][62] These lesions manifest as sharply defined areas of retinal depigmentation visible on fundus examination, resulting from progressive cell death without neovascularization, distinguishing GA from wet AMD.[63] The condition's pathophysiology involves dysregulation of the complement system, oxidative stress, and inflammation, which accelerate RPE and photoreceptor atrophy, though exact causal mechanisms remain under investigation through histopathological and genetic studies.[64] Epidemiologically, GA affects an estimated 5 million individuals globally, with approximately 1 million cases in the United States, accounting for about 20% of legal blindness due to AMD.[65][66] Prevalence escalates sharply with age, from 0.7% in those aged 70 years to 2.9% by age 80, reaching nearly 20% in individuals over 85; in developed nations, it impacts roughly 1 in 29 people over 75.[67][68] Risk factors include advanced age, genetic variants in complement genes (e.g., CFH), smoking, and Caucasian ethnicity, with bilateral involvement common in over 70% of cases.[69] GA progression is nonlinear and variable, with lesions expanding at an average rate of 1.5-2.5 mm² per year, though longitudinal studies report total atrophy increases of up to 6.4 mm² over five years across affected eyes.[70] Advanced imaging modalities like fundus autofluorescence (FAF) and spectral-domain optical coherence tomography (SD-OCT) enable quantification of lesion growth, revealing patterns such as perifoveal coalescence and foveal involvement that correlate with reading speed decline and scotoma expansion.[71] Recent deep learning models trained on FAF or OCT data predict 1-year lesion growth with high accuracy (e.g., via random forest algorithms assessing retinal sensitivity loss), aiding personalized prognosis but not yet altering standard clinical management.[72][73] Medically, GA management historically focused on supportive measures like low-vision aids, as no therapies halted progression until 2023 FDA approvals of complement inhibitors. Pegcetacoplan (Syfovre), a C3 inhibitor administered via intravitreal injection every 25-60 days, was approved on February 17, 2023, based on phase 3 OAKS and DERBY trials showing 20-30% reduction in GA lesion growth over 24 months, with greater effects in monthly dosing and toward the fovea.[74][75] Avacincaptad pegol (Izervay), a C5 inhibitor approved in August 2023, similarly slows progression by 27-30% in the GATHER trials, though both carry risks of ocular inflammation and endophthalmitis (0.6-1.6% incidence).[76] As of 2025, these remain the only approved treatments, with ongoing phase 2/3 trials exploring oral agents and stem cell therapies, but no evidence of vision restoration; patient selection emphasizes extrafoveal GA to maximize functional preservation.[77][78]Computing and algorithms
Genetic algorithms (GAs) are a class of evolutionary computation methods that simulate natural selection processes to solve optimization and search problems in computing. Introduced by John H. Holland in his 1975 book Adaptation in Natural and Artificial Systems, GAs operate on a population of candidate solutions represented as chromosomes, typically binary strings or other encodings, evolving them over generations to converge on high-fitness outcomes.[79][80] The core algorithm initializes a random population, evaluates fitness via an objective function, and iteratively applies three operators: selection, crossover, and mutation. Selection favors individuals with superior fitness—often using techniques like roulette wheel or tournament selection—to form a mating pool, probabilistically mimicking survival of the fittest. Crossover recombines genetic material from paired parents at random points, producing offspring that inherit advantageous traits, with rates typically around 0.6–0.9 to balance exploration and exploitation. Mutation introduces small random alterations to offspring bits or parameters, at low probabilities (e.g., 0.001–0.01 per locus), preventing premature convergence and maintaining diversity. These steps repeat until termination criteria, such as maximum generations or fitness thresholds, are met.[81][82][83] In terms of computational efficiency, GAs excel in rugged, multimodal search spaces where gradient-based or exhaustive methods fail due to high dimensionality or NP-hardness, trading guaranteed optimality for scalable heuristics via parallel population evaluation. Historical developments include schema theorem proofs by Holland in the 1970s, justifying building-block hypothesis for rapid adaptation, and extensions like steady-state GAs in the 1980s for incremental updates, reducing evaluations from O(generations × population size) in generational models. Modern variants incorporate adaptive parameters and hybridizations with local search to enhance convergence speed, as seen in implementations solving problems infeasible for deterministic algorithms.[84][85] A prominent application is the traveling salesman problem (TSP), an NP-hard optimization task minimizing tour length across n cities. GAs encode tours as permutation chromosomes, using order-based crossover to preserve feasibility and mutation via swaps or inversions; for instance, on benchmark instances like TSPLIB with 50–100 cities, tuned GAs achieve near-optimal solutions (within 1–5% of best-known) in under 10^5 fitness evaluations, outperforming naive brute-force (O(n!)) by orders of magnitude.[86][87]Other technical applications
In software engineering, general availability (GA) designates the final release stage of a product or feature to the broader market and production environments, succeeding preview, beta, or limited rollout phases to confirm reliability, security, and full support. This transition typically occurs after rigorous internal validation, enabling scalable deployment; for example, Microsoft declared GA for in-app notifications in Power Platform model-driven apps on April 28, 2022, following a July 2021 preview.[88] Oracle employs GA for annual product updates in sectors like energy management, issuing three such releases per calendar year with 12-month support each, aligning with enterprise deployment cycles in the 2020s.[89] In engineering measurements, gauge (GA) systems standardize wire, sheet, and tubing dimensions for applications in electrical conduction, structural integrity, and fluid handling, where precise thickness correlates to load-bearing or current-carrying capacity. The American Wire Gauge (AWG) inversely scales size—thinner wires have higher numbers—with AWG 12 (diameter approximately 2.05 mm) or 14 (1.63 mm) standard for household circuits rated up to 20-15 amperes, per resistance and ampacity tables derived from cross-sectional area.[90] Complementarily, the Birmingham Wire Gauge (BWG), or Stubs' gauge, applies to ferrous wire and tube walls, specifying BWG 16 at 0.065 inches (1.65 mm) thick for drill rods and piping, ensuring interoperability in manufacturing standards without reliance on metric equivalents alone.[91] These GA metrics, verified against empirical draw ratios from wire production (e.g., 92% area reduction per AWG step), underpin safety codes like those from the National Electrical Code for preventing overheating in technical assemblies.[92]Sports
Athletic associations
The Georgia Athletic Directors Association (GA) supports athletic directors across Georgia's educational institutions by offering professional training, leadership development, and resources to advance interscholastic athletics.[93] It serves over 200 members, focusing on fostering ethical practices and preparing student-athletes for citizenship through organized sports programs.[94] Affiliated with the National Interscholastic Athletic Administrators Association (NIAAA), National Federation of State High School Associations (NFHS), Georgia High School Association (GHSA), and Georgia Athletic Coaches Association (GACA), the GA emphasizes certification programs such as Registered Athletic Administrator (RAA), Certified Athletic Administrator (CAA), and Certified Master Athletic Administrator (CMAA).[93] Key activities include annual state and national conferences, a quarterly journal titled Interscholastic Athletic Administrator, and the Leadership Training Institute for professional learning units (PLUs). Members receive benefits like $2,500 term life insurance and $2,000,000 liability coverage, alongside the association's provision of $1,500 in annual student-athlete scholarships.[93]Statistical terms
In ice hockey, particularly in the National Hockey League (NHL), GA denotes "goals against," representing the total number of goals scored by the opposing team while a specific goaltender is in net, excluding empty-net goals and those scored in shootouts.[95][96] This metric serves as a foundational defensive statistic for evaluating goaltender performance, often aggregated into goals against average (GAA), calculated as (GA × 60) divided by total minutes played, yielding goals allowed per 60 minutes of regulation and overtime play.[95][97] For example, in the 2023-2024 NHL season, GAA calculations highlighted variability among starting goaltenders, with league-wide averages influenced by factors like team defensive strength and shot volume faced.[98] In soccer (association football), GA similarly refers to "goals against," quantifying the total goals conceded by a team or goalkeeper over a season or tournament, commonly featured in league standings alongside goals for (GF) to compute goal difference (GD = GF - GA).[99][100] This raw count does not normalize for matches played or minutes exposed, distinguishing it from per-game averages used in goalkeeper evaluations. In the 2023-2024 Premier League season, for instance, Manchester City recorded the lowest team GA at 34 goals across 38 matches, underscoring their defensive efficiency, while relegated teams like Sheffield United tallied 101 GA, reflecting poor backline performance.[101] Lower GA correlates with higher league positions, as goal difference serves as a primary tiebreaker in points-based tables.[99]Other uses
Military ranks
General of the Army (abbreviated as GA) is the highest attainable rank in the United States Army, classified as a five-star general officer position reserved primarily for wartime use.[102] Established by an act of Congress on December 14, 1944, the rank authorized the appointment of no more than four officers initially, though five ultimately received it, with insignia consisting of five silver stars arranged in a horizontal line on the shoulder board.[103] [104] In the hierarchy of precedence, GA outranks the four-star general (GEN) and holds special pay grade status equivalent to O-11, reflecting its exceptional authority over large-scale theater commands.[102] The rank has not been conferred since 1950 and remains dormant in peacetime, with living holders retaining the title for life.[105] Five officers have held the rank of General of the Army:| Officer | Date of Rank |
|---|---|
| George C. Marshall | December 16, 1944 |
| Douglas MacArthur | December 18, 1944 |
| Dwight D. Eisenhower | December 20, 1944 |
| Henry H. Arnold | December 21, 1944 |
| Omar N. Bradley | September 22, 1950 |