In statistics , epidemiology , marketing and demography , a cohort is a group of subjects who share a defining characteristic (typically subjects who experienced a common event in a selected time period, such as birth or graduation).
100-417: Human life expectancy is a statistical measure of the estimate of the average remaining years of life at a given age. The most commonly used measure is life expectancy at birth (LEB, or in demographic notation e 0 , where e x denotes the average life remaining at age x ). This can be defined in two ways. Cohort LEB is the mean length of life of a birth cohort (in this case, all individuals born in
200-711: A "Britannica Checked" stamp, to distinguish it from the user-generated content. On 14 September 2010, Encyclopædia Britannica, Inc. announced a partnership with mobile phone development company Concentric Sky to launch a series of iPhone products aimed at the K–12 market. On 20 July 2011, Encyclopædia Britannica, Incorporated announced that Concentric Sky had ported the Britannica Kids product line to Intel's Intel Atom -based Netbooks and on 26 October 2011 that it had launched its encyclopaedia as an iPad app . In 2010, Britannica released Britannica ImageQuest,
300-425: A database of images. In March 2012, it was announced that the company would cease printing the encyclopaedia set, and that it would focus on its online version. On 7 June 2018, Britannica released a Google Chrome extension , "Britannica Insights", which shows snippets of information from Britannica Online whenever the user performs a Google Search , in a box to the right of Google's results. Britannica Insights
400-425: A given year) and can be computed only for cohorts born so long ago that all their members have died. Period LEB is the mean length of life of a hypothetical cohort assumed to be exposed, from birth through death, to the mortality rates observed at a given year. National LEB figures reported by national agencies and international organizations for human populations are estimates of period LEB. Human remains from
500-652: A guide to the Macropædia ; readers are advised to study the Propædia outline to understand a subject's context and to find more detailed articles. Over 70 years, the size of the Britannica has remained steady, with about 40 million words on half a million topics. Though published in the United States since 1901, the Britannica has for the most part maintained British English spelling . From 1985,
600-582: A healthy diet. The World Health Organization announced that the COVID-19 pandemic reversed the trend of steady gain in life expectancy at birth. The pandemic wiped out nearly a decade of progress in improving life expectancy. During the last 200 years, African countries have generally not had the same improvements in mortality rates that have been enjoyed by countries in Asia, Latin America, and Europe. This
700-399: A link to decreased thyroid activity, resulting in their lowered metabolic rate. Cohort (statistics) Cohort data can oftentimes be more advantageous to demographers than period data. Because cohort data is honed to a specific time period, it is usually more accurate. It is more accurate because it can be tuned to retrieve custom data for a specific study. In addition, cohort data
800-476: A lower life expectancy than average include transplant recipients and the obese. Education on all levels has been shown to be strongly associated with increased life expectancy. This association may be due partly to higher income, which can lead to increased life expectancy. Despite the association, among identical twin pairs with different education levels, there is only weak evidence of a relationship between educational attainment and adult mortality. According to
900-480: A paper from 2015, the mortality rate for the Caucasian population in the United States from 1993 to 2001 is four times higher for those who did not complete high school compared to those who have at least 16 years of education. In fact, within the U.S. adult population, people with less than a high school education have the shortest life expectancies. Preschool education also plays a large role in life expectancy. It
1000-594: A partnership with YouTube in which verified Britannica content appeared on the site as an antidote to user-generated video content that could be false or misleading. Krishnan, an educator at New York University 's Stern School of Business , believes in the "transformative power of education" and set steering the company toward solidifying its place among leaders in educational technology and supplemental curriculum. Krishnan aimed at providing more useful and relevant solutions to customer needs, extending and renewing Britannica's historical emphasis on "utility", which had been
1100-574: A promising candidate for further research within the field. This study suggests that high levels of iron in the blood likely reduce, and genes involved in metabolising iron likely increase healthy years of life in humans. A follow-up study which investigated the genetics of frailty and self-rated health in addition to healthspan, lifespan, and longevity also highlighted haem metabolism as an important pathway, and found genetic variants which lower blood protein levels of LPA and VCAM1 were associated with increased healthy lifespan. In developed countries,
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#17327658061771200-627: A single article; however, 64 contributed to three articles, 23 contributed to four articles, 10 contributed to five articles, and 8 contributed to more than five articles. An exceptionally prolific contributor is Christine Sutton of the University of Oxford , who contributed 24 articles on particle physics . While Britannica 's authors have included writers such as Albert Einstein , Marie Curie , and Leon Trotsky , as well as notable independent encyclopaedists such as Isaac Asimov , some have been criticized for lack of expertise. In 1911,
1300-590: A society with a life expectancy of 30, it may nevertheless be common to have a 40-year remaining timespan at age 5 (but not a 60-year one). Aggregate population measures—such as the proportion of the population in various age groups—are also used alongside individual-based measures—such as formal life expectancy—when analyzing population structure and dynamics. Pre-modern societies had universally higher mortality rates and lower life expectancies at every age for both males and females. Life expectancy, longevity , and maximum lifespan are not synonymous. Longevity refers to
1400-405: A study guide, as it puts subjects in their proper perspective and suggests a series of Britannica articles for the student wishing to learn a topic in depth. However, libraries have found that it is scarcely used for this purpose, and reviewers have recommended that it be dropped from the encyclopaedia. The Propædia contains color transparencies of human anatomy and several appendices listing
1500-472: A tight budget for food energy called caloric restriction . Caloric restriction observed in many animals (most notably mice and rats) shows a near doubling of life span from a very limited calorific intake. Support for the theory has been bolstered by several new studies linking lower basal metabolic rate to increased life expectancy. That is the key to why animals like giant tortoises can live so long. Studies of humans with life spans of at least 100 have shown
1600-748: A total of 13 million "missing Americans" from 1980 to 2021, deaths that would have been averted if it had the standard mortality rate of " wealthy nations ". The annual number of "missing Americans" has been increasing, with 622,534 in 2019 alone. Most excess deaths in the United States can largely be attributed to increasing obesity , alcoholism , drug overdoses , car accidents , suicides , and murders , with poor sleep , unhealthy diets , and loneliness being linked to most of them. Black Americans have generally shorter life expectancies than their White American counterparts. For example, white Americans in 2010 are expected to live until age 78.9, but black Americans only until age 75.1. This 3.8-year gap, however,
1700-516: Is a general knowledge English-language encyclopaedia . It has been published by Encyclopædia Britannica, Inc. since 1768, although the company has changed ownership seven times. The encyclopaedia is maintained by about 100 full-time editors and more than 4,000 contributors. The 2010 version of the 15th edition, which spans 32 volumes and 32,640 pages, was the last printed edition. Since 2016, it has been published exclusively as an online encyclopaedia . Printed for 244 years,
1800-656: Is a partial explanation. Another explanation is the unguarded X hypothesis . According to this hypothesis, one reason for why the average lifespan of males is not as long as that of females––by 18% on average, according to the study––is that they have a Y chromosome which cannot protect an individual from harmful genes expressed on the X chromosome, while a duplicate X chromosome, as present in female organisms, can ensure harmful genes are not expressed . In developed countries, starting around 1880, death rates decreased faster among women, leading to differences in mortality rates between males and females. Before 1880, death rates were
1900-661: Is a website with more than 120,000 articles and is updated regularly. It has daily features, updates and links to news reports from The New York Times and the BBC . As of 2009 , roughly 60% of Encyclopædia Britannica's revenue came from online operations, of which around 15% came from subscriptions to the consumer version of the websites. As of 2006 , subscriptions were available on a yearly, monthly or weekly basis. Special subscription plans are offered to schools, colleges and libraries; such institutional subscribers constitute an important part of Britannica's business. Beginning in early 2007,
2000-492: Is also likely to be affected by exposure to high levels of highway air pollution or industrial air pollution . This is one way that occupation can have a major effect on life expectancy. Coal miners (and in prior generations, asbestos cutters) often have lower life expectancies than average. Other factors affecting an individual's life expectancy are genetic disorders, drug use, tobacco smoking , excessive alcohol consumption, obesity, access to health care, diet, and exercise. In
2100-524: Is an average, a particular person may die many years before or after the expected survival. Life expectancy is also used in plant or animal ecology , and in life tables (also known as actuarial tables). The concept of life expectancy may also be used in the context of manufactured objects, though the related term shelf life is commonly used for consumer products, and the terms "mean time to breakdown" and " mean time between failures " are used in engineering. The earliest documented work on life expectancy
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#17327658061772200-417: Is considered to have a more left-leaning orientation. The 15th edition (1974–2010) has a three-part structure: a 12-volume Micropædia of short articles (generally fewer than 750 words), a 17-volume Macropædia of long articles (two to 310 pages), and a single Propædia volume to give a hierarchical outline of knowledge. The Micropædia was meant for quick fact-checking and as
2300-490: Is continually reprinted, with every article updated on a schedule. In the 21st century, the Britannica suffered first from competition with the digital multimedia encyclopaedia Microsoft Encarta , and later with the online peer-produced encyclopaedia Misplaced Pages . In March 2012, it announced it would no longer publish printed editions and would focus instead on the online version. Britannica has been assessed as being more politically centrist compared to Misplaced Pages, which
2400-524: Is estimated to be less than 10%, meaning the majority of variation in lifespan is attributable due to differences in environment rather than genetic variation . However, researchers have identified regions of the genome which can influence the length of life and the number of years lived in good health. For example, a genome-wide association study of 1 million lifespans found 12 genetic loci which influenced lifespan by modifying susceptibility to cardiovascular and smoking-related disease . The locus with
2500-462: Is for children aged three to six (issued 1974 to 1991). There have been, and are, several abridged Britannica encyclopaedias. The single-volume Britannica Concise Encyclopædia has 28,000 short articles condensing the larger 32-volume Britannica ; there are authorized translations in languages such as Chinese created by Encyclopedia of China Publishing House and Vietnamese . Compton's by Britannica , first published in 2007, incorporating
2600-459: Is highly sensitive to the rate of death in the first few years of life. Because of this sensitivity, LEB can be grossly misinterpreted, leading to the belief that a population with a low LEB would have a small proportion of older people. A different measure, such as life expectancy at age 5 (e 5 ), can be used to exclude the effect of infant mortality to provide a simple measure of overall mortality rates other than in early childhood. For instance, in
2700-409: Is known to have lived. According to a study by biologists Bryan G. Hughes and Siegfried Hekimi, there is no evidence for limit on human lifespan. However, this view has been questioned on the basis of error patterns. A theoretical study shows that the maximum life expectancy at birth is limited by the human life characteristic value δ, which is around 104 years. The following information is derived from
2800-464: Is most apparent by the impact of AIDS on many African countries. According to projections made by the United Nations in 2002, the life expectancy at birth for 2010–2015 (if HIV/AIDS did not exist) would have been: On average, eastern Europeans tend to live shorter lives than their western counterparts. For example, Spaniards from Madrid can expect to live to 85, but Bulgarians from
2900-400: Is not affected by tempo effects , unlike period data. However, cohort data can be disadvantageous in the sense that it can take a long amount of time to collect the data necessary for the cohort study . Another disadvantage of cohort studies is that it can be extremely costly to carry out, since the study will go on for a long period of time, demographers often require sufficient funds to fuel
3000-493: Is on the subject of the United States, and it resulted from merging separate articles on the individual US states . A 2013 "Global Edition" of Britannica contained approximately 40,000 articles. Information can be found in the Britannica by following the cross-references in the Micropædia and Macropædia ; these are sparse, however, averaging one cross-reference per page. Readers are instead recommended to consult
3100-437: Is that mitochondrial mutations which shorten lifespan continue to be expressed in males (but less so in females) because mitochondria are inherited only through the mother. By contrast, natural selection weeds out mitochondria that reduce female survival; therefore, such mitochondria are less likely to be passed on to the next generation. This thus suggests that females tend to live longer than males. The authors claim that this
Life expectancy - Misplaced Pages Continue
3200-416: Is that if predation or accidental deaths prevent most individuals from living to an old age, there will be less natural selection to increase the intrinsic life span. That finding was supported in a classic study of opossums by Austad; however, the opposite relationship was found in an equally prominent study of guppies by Reznick. One prominent and very popular theory states that lifespan can be lengthened by
3300-503: Is the lowest it has been since 1975 at the latest, the greatest difference being 7.1 years in 1993. In contrast, Asian American women live the longest of all ethnic and gender groups in the United States, with a life expectancy of 85.8 years. The life expectancy of Hispanic Americans is 81.2 years. In 2023, the life expectancy was 84.5 in Japan, 4.2 years above the OECD average, and one of
3400-414: The Britannica 's Board of Directors. In 2003, former management consultant Jorge Aguilar-Cauz was appointed President of Encyclopædia Britannica, Incorporated. Cauz is the senior executive and reports directly to the Britannica 's Board of Directors. Cauz has been pursuing alliances with other companies and extending the Britannica brand to new educational and reference products, continuing
3500-511: The Britannica consisted of four parts: the Micropædia , the Macropædia , the Propædia , and a two-volume index. The Britannica 's articles are contained in the Micro- and Macropædia , which encompass 12 and 17 volumes, respectively, each volume having roughly one thousand pages. The 2007 Macropædia has 699 in-depth articles, ranging in length from two pages to 310 pages, with references and named contributors. In contrast,
3600-590: The Britannica has been revised on a regular schedule, with at least 10% of the articles considered for revision each year. According to one Britannica website, 46% of the articles in the 2007 edition were revised over the preceding three years; however, according to another Britannica website, only 35% of the articles were revised over the same period. The alphabetization of articles in the Micropædia and Macropædia follows strict rules. Diacritical marks and non-English letters are ignored, while numerical entries such as " 1812, War of " are alphabetized as if
3700-425: The Britannica included five Senior Editors and nine Associate Editors, supervised by Dale Hoiberg and four others. The editorial staff helped to write the articles of the Micropædia and some sections of the Macropædia . As of 2012, Britannica had an editorial board of advisors, which included a number of distinguished figures, primarily scholars from a variety of disciplines. Past and present members of
3800-479: The Britannica made articles freely available if they are hyperlinked from an external site. Non-subscribers are served pop-ups and advertising. On 20 February 2007, Encyclopædia Britannica, Incorporated announced that it was working with mobile phone search company AskMeNow to launch a mobile encyclopaedia. Users will be able to send a question via text message, and AskMeNow will search Britannica 's 28,000-article concise encyclopaedia to return an answer to
3900-493: The Britannica turned to focus more on its online edition. The Encyclopædia Britannica has been compared with other print encyclopaedias, both qualitatively and quantitatively. A well-known comparison is that of Kenneth Kister , who gave a qualitative and quantitative comparison of the 1993 Britannica with two comparable encyclopaedias, Collier's Encyclopedia and the Encyclopedia Americana . For
4000-521: The Britannica was the longest-running in-print encyclopaedia in the English language. It was first published between 1768 and 1771 in the Scottish capital of Edinburgh , in three volumes. The encyclopaedia grew in size; the second edition was 10 volumes, and by its fourth edition (1801–1810), it had expanded to 20 volumes. Its rising stature as a scholarly work helped recruit eminent contributors, and
4100-548: The Industrial Revolution , the life expectancy of children increased dramatically. Recorded deaths among children under the age of 5 years fell in London from 74.5% of the recorded births in 1730–49 to 31.8% in 1810–29, though this overstates mortality and its fall because of net immigration (hence more dying in the metropolis than were born there) and incomplete registration (particularly of births, and especially in
Life expectancy - Misplaced Pages Continue
4200-688: The Royal Society of Edinburgh , and cultural anthropologist Michael Wesch . The Propædia and its Outline of Knowledge were produced by dozens of editorial advisors under the direction of Mortimer J. Adler . Roughly half of these advisors have since died, including some of the Outline's chief architects – Rene Dubos (d. 1982), Loren Eiseley (d. 1977), Harold D. Lasswell (d. 1978), Mark Van Doren (d. 1972), Peter Ritchie Calder (d. 1982) and Mortimer J. Adler (d. 2001). The Propædia also lists just under 4,000 advisors who were consulted for
4300-471: The University of Michigan found that life expectancy actually increased during the Great Depression , and during recessions and depressions in general. The authors suggest that when people are working at a more extreme degree during prosperous economic times, they undergo more stress , exposure to pollution , and the likelihood of injury among other longevity-limiting factors. Life expectancy
4400-468: The gastrointestinal tract ; the mentally ill have a four times risk of gastrointestinal disease. As of 2020 and the COVID-19 pandemic, researchers have found an increased risk of death in the mentally ill. The life expectancy of people with diabetes, which is 9.3% of the U.S. population, is reduced by roughly 10–20 years. People over 60 years old with Alzheimer's disease have about a 50% life expectancy of 3–10 years. Other demographics that tend to have
4500-463: The 1961 Encyclopædia Britannica and other sources, some with questionable accuracy. Unless otherwise stated, it represents estimates of the life expectancies of the world population as a whole. In many instances, life expectancy varied considerably according to class and gender. Life expectancy at birth takes account of infant mortality and child mortality but not prenatal mortality. Life expectancy at age 1 reached 34–41 remaining years for
4600-500: The 2007 Micropædia has roughly 65,000 articles, the vast majority (about 97%) of which contain fewer than 750 words, no references, and no named contributors. The Micropædia articles are intended for quick fact-checking and to help in finding more thorough information in the Macropædia . The Macropædia articles are meant as authoritative, well-written commentaries on their subjects, as well as storehouses of information not covered elsewhere. The longest article (310 pages)
4700-483: The 20th century, successful competitors included Collier's Encyclopedia , the Encyclopedia Americana , and the World Book Encyclopedia . Nevertheless, from the 9th edition onwards, the Britannica was widely considered to have the greatest authority of any general English-language encyclopaedia, especially because of its broad coverage and eminent authors. The print version of the Britannica
4800-420: The 67–75% surviving the first year. For the 55-65% surviving to age 5, remaining life expectancy reached around 40–45, while the ~50% reaching age 10 could expect another 40 years of life. Average remaining years fell to 33–39 at age 15; ~20 at age 40; 14–18 at age 50; ~10–12 at age 60; and ~6–7 at age 70. Only half of the people born in the early 19th century made it past their 50th birthday. In contrast, 97% of
4900-478: The 9th (1875–1889) and 11th editions (1911) are landmark encyclopaedias for scholarship and literary style. Starting with the 11th edition and following its acquisition by an American firm, the Britannica shortened and simplified articles to broaden its appeal to the North American market. In 1933, the Britannica became the first encyclopaedia to adopt "continuous revision", in which the encyclopaedia
5000-579: The Google Chrome browser that served up edited, fact-checked Britannica information with queries on search engines such as Google, Yahoo, and Bing. Its purpose, the company said, was to "provide trusted, verified information" in conjunction with search results that were thought to be increasingly unreliable in the era of misinformation and "fake news." The product was quickly followed by Britannica School Insights, which provided similar content for subscribers to Britannica's online classroom solutions, and
5100-798: The Life and Works of the Bard (Wiley, 2006). The Britannica Ultimate Reference Suite 2012 DVD contains over 100,000 articles. This includes regular Britannica articles, as well as others drawn from the Britannica Student Encyclopædia , and the Britannica Elementary Encyclopædia. The package includes a range of supplementary content including maps, videos, sound clips, animations and web links. It also offers study tools and dictionary and thesaurus entries from Merriam-Webster . Britannica Online
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#17327658061775200-623: The United States increased by more than 30 years, of which 25 years can be attributed to advances in public health. There are great variations in life expectancy between different parts of the world, mostly caused by differences in public health , medical care, and diet. Human beings are expected to live on average 60 years in Eswatini and 82.6 years in Japan. An analysis published in 2011 in The Lancet attributes Japanese life expectancy to equal opportunities , excellent public health , and
5300-462: The United States, the number of centenarians grew from 32,194 in 1980 to 71,944 in November 2010 (232 centenarians per million inhabitants). Mental illness is reported to occur in approximately 18% of the average American population. The mentally ill have been shown to have a 10- to 25-year reduction in life expectancy. Generally, the reduction of lifespan in the mentally ill population compared to
5400-427: The alphabetical index or the Propædia , which organizes the Britannica 's contents by topic. The core of the Propædia is its "Outline of Knowledge", which aims to provide a logical framework for all human knowledge. Accordingly, the Outline is consulted by the Britannica 's editors to decide which articles should be included in the Micro- and Macropædia . The Outline can also be used as
5500-518: The board have included: non-fiction author Nicholas Carr , religion scholar Wendy Doniger , political economist Benjamin M. Friedman , Council on Foreign Relations President Emeritus Leslie H. Gelb , computer scientist David Gelernter , Physics Nobel laureate Murray Gell-Mann , Carnegie Corporation of New York President Vartan Gregorian , philosopher Thomas Nagel , cognitive scientist Donald Norman , musicologist Don Michael Randel , Stewart Sutherland, Baron Sutherland of Houndwood , President of
5600-444: The company announced that the 2010 edition would be the last printed version. This was part of a move by the company to adapt to the times and focus on its future using digital distribution. The peak year for the printed encyclopaedia was 1990, when 120,000 sets were sold, but sales had dropped to 40,000 per annum by 1996. There were 12,000 sets of the 2010 edition printed, of which 8,000 had been sold by March 2012. By late April 2012,
5700-420: The company would be accepting edits and additions to the online Britannica website from the public. The published edition of the encyclopaedia will not be affected by the changes. Individuals wishing to edit the Britannica website will have to register under their real name and address prior to editing or submitting their content. All edits submitted will be reviewed and checked and will have to be approved by
5800-413: The disparity is amongst the highest in the world : life expectancy for males in the heavily deprived Calton area stands at 54, which is 28 years less than in the affluent area of Lenzie , which is only 8 km (5.0 mi) away. A 2013 study found a pronounced relationship between economic inequality and life expectancy. However, in contrast, a study by José A. Tapia Granados and Ana Diez Roux at
5900-399: The earlier period). English life expectancy at birth reached 41 years in the 1840s, 43 in the 1870s and 46 in the 1890s, though infant mortality remained at around 150 per thousand throughout this period. Public health measures are credited with much of the recent increase in life expectancy. During the 20th century, despite a brief drop due to the 1918 flu pandemic , the average lifespan in
6000-460: The early Bronze Age indicate an LEB of 24. In 2019, world LEB was 73.3. A combination of high infant mortality and deaths in young adulthood from accidents, epidemics , plagues, wars, and childbirth, before modern medicine was widely available, significantly lowers LEB. For example, a society with a LEB of 40 would have relatively few people dying at exactly 40: most will die before 30 or after 55. In populations with high infant mortality rates, LEB
6100-417: The encyclopaedia's professional staff. Contributions from non-academic users will sit in a separate section from the expert-generated Britannica content, as will content submitted by non- Britannica scholars. Articles written by users, if vetted and approved, will also only be available in a special section of the website, separate from the professional articles. Official Britannica material would carry
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#17327658061776200-459: The encyclopaedias had an article on sexual harassment in 1994. In the accuracy category, the Britannica received one "D" and seven "A"s, Encyclopedia Americana received eight "A"s, and Collier's received one "D" and seven "A"s; thus, Britannica received an average score of 92% for accuracy to Americana 's 95% and Collier's 92%. In the timeliness category, Britannica averaged an 86% to Americana' s 90% and Collier's 85%. In 2013,
6300-536: The existing literature, Kalben concluded that the fact that women live longer than men was observed at least as far back as 1750 and that, with relatively equal treatment, today males in all parts of the world experience greater mortality than females. However, Kalben's study was restricted to data in Western Europe alone, where the demographic transition occurred relatively early. United Nations statistics from mid-twentieth century onward, show that in all parts of
6400-407: The female mortality rate from breast cancer and cervical cancer. In the past, mortality rates for females in child-bearing age groups were higher than for males at the same age. A paper from 2015 found that female foetuses have a higher mortality rate than male foetuses. This finding contradicts papers dating from 2002 and earlier that attribute the male sex to higher in-utero mortality rates. Among
6500-607: The former Compton's Encyclopedia , is aimed at 10- to 17-year-olds and consists of 26 volumes and 11,000 pages. Since 1938, Encyclopædia Britannica, Inc. has published annually a Book of the Year covering the past year's events. A given edition of the Book of the Year is named in terms of the year of its publication, though the edition actually covers the events of the previous year. The company also publishes several specialized reference works, such as Shakespeare: The Essential Guide to
6600-518: The gap in life expectancy between men and women decreasing in later life. This may be attributable to the effects of infant mortality and young adult death rates. Some argue that shorter male life expectancy is merely another manifestation of the general rule, seen in all mammal species, that larger-sized individuals within a species tend, on average, to have shorter lives. This biological difference occurs because women have more resistance to infections and degenerative diseases. In her extensive review of
6700-594: The highest in the world. Japan's high life expectancy can largely be explained by their healthy diets, which are low on salt , fat , and red meat. For these reasons, Japan has a low obesity rate, and ultimately low mortality from heart disease and cancers Cities also experience a wide range of life expectancy based on neighborhood breakdowns. This is largely due to economic clustering and poverty conditions that tend to associate based on geographic location. Multi-generational poverty found in struggling neighborhoods also contributes. In American cities such as Cincinnati ,
6800-427: The historian George L. Burr wrote: With a temerity almost appalling, [the Britannica contributor, Mr. Philips] ranges over nearly the whole field of European history, political, social, ecclesiastical... The grievance is that [this work] lacks authority. This, too—this reliance on editorial energy instead of on ripe special learning—may, alas, be also counted an "Americanizing": for certainly nothing has so cheapened
6900-492: The largest effect is APOE . Carriers of the APOE ε4 allele live approximately one year less than average (per copy of the ε4 allele), mainly due to increased risk of Alzheimer's disease . In July 2020, scientists identified 10 genomic loci with consistent effects across multiple lifespan-related traits, including healthspan , lifespan, and longevity . The genes affected by variation in these loci highlighted haem metabolism as
7000-602: The life expectancy gap between low income and high-income neighborhoods touches 20 years. Economic circumstances also affect life expectancy. For example, in the United Kingdom, life expectancy in the wealthiest and richest areas is several years higher than in the poorest areas. This may reflect factors such as diet and lifestyle, as well as access to medical care. It may also reflect a selective effect: people with chronic life-threatening illnesses are less likely to become wealthy or to reside in affluent areas. In Glasgow ,
7100-480: The liver . Men are also more likely to die from injuries, whether unintentional (such as occupational , war , or car wrecks ) or intentional ( suicide ). Men are also more likely to die from most of the leading causes of death (some already stated above) than women. Some of these in the United States include cancer of the respiratory system, motor vehicle accidents, suicide, cirrhosis of the liver, emphysema, prostate cancer, and coronary heart disease. These far outweigh
7200-470: The mentally stable population has been studied and documented. The greater mortality of people with mental disorders may be due to death from injury, from co-morbid conditions, or medication side effects. For instance, psychiatric medications can increase the risk of developing diabetes . It has been shown that the psychiatric medication olanzapine can increase risk of developing agranulocytosis , among other comorbidities. Psychiatric medicines also affect
7300-637: The number had been written out ("Eighteen-twelve, War of"). Articles with identical names are ordered first by persons, then by places, then by things. Rulers with identical names are organized first alphabetically by country and then by chronology; thus, Charles III of France precedes Charles I of England , listed in Britannica as the ruler of Great Britain and Ireland. (That is, they are alphabetized as if their titles were "Charles, France, 3" and "Charles, Great Britain and Ireland, 1".) Similarly, places that share names are organized alphabetically by country, then by ever-smaller political divisions. In March 2012,
7400-471: The number of centenarians is increasing at approximately 5.5% per year, which means doubling the centenarian population every 13 years, pushing it from some 455,000 in 2009 to 4.1 million in 2050. Japan is the country with the highest ratio of centenarians (347 for every 1 million inhabitants in September 2010). Shimane Prefecture had an estimated 743 centenarians per million inhabitants. In
7500-570: The open PubMed Central library of the National Library of Medicine . The Internet tends to provide more current coverage than print media, due to the ease with which material on the Internet can be updated. In rapidly changing fields such as science, technology, politics, culture and modern history, the Britannica has struggled to stay up to date, a problem first analysed systematically by its former editor Walter Yust. Eventually,
7600-455: The people born in 21st century England and Wales can expect to live longer than 50 years. English life expectancy at birth averaged about 36 years in the 17th and 18th centuries, one of the highest levels in the world although infant and child mortality remained higher than in later periods. Life expectancy was under 25 years in the early Colony of Virginia , and in seventeenth-century New England, about 40% died before reaching adulthood. During
7700-488: The present, female human life expectancy is greater than that of males, despite females having higher morbidity rates (see health survival paradox ). There are many potential reasons for this. Traditional arguments tend to favor sociology-environmental factors: historically, men have generally consumed more tobacco , alcohol , and drugs than women in most societies, and are more likely to die from many associated diseases such as lung cancer , tuberculosis , and cirrhosis of
7800-451: The quantitative analysis, ten articles were selected at random— circumcision , Charles Drew , Galileo , Philip Glass , heart disease , IQ , panda bear , sexual harassment , Shroud of Turin and Uzbekistan —and letter grades of A–D or F were awarded in four categories: coverage, accuracy, clarity, and recency. In all four categories and for all three encyclopaedias, the four average grades fell between B− and B+ , chiefly because none of
7900-586: The query. Daily topical features sent directly to users' mobile phones were also planned. On 3 June 2008, an initiative to facilitate collaboration between online expert and amateur scholarly contributors for Britannica's online content (in the spirit of a wiki ), with editorial oversight from Britannica staff, was announced. Approved contributions would be credited, though contributing automatically grants Encyclopædia Britannica, Incorporated perpetual, irrevocable license to those contributions. On 22 January 2009, Britannica's president, Jorge Cauz , announced that
8000-485: The region of Severozapaden are predicted to live just past their 73rd birthday. This is in large part due to poor health habits, such as heavy smoking and high alcoholism in the region, and environmental actors, such as high air pollution. In 2022, the life expectancy was 77.5 in the United States , a decline from 2014, but an increase from 2021. In what has been described as a "life expectancy crisis", there were
8100-419: The relatively long lifespan of some members of a population. Maximum lifespan is the age at death for the longest-lived individual of a species. Mathematically, life expectancy is denoted e x {\displaystyle e_{x}} and is the mean number of years of life remaining at a given age x {\displaystyle x} , with a particular mortality . Because life expectancy
8200-450: The remaining copies of the 2010 edition had sold out at Britannica's online store. As of 2016 , a replica of Britannica's 1768 first edition is available via the online store. Britannica Junior was first published in 1934 as 12 volumes. It was expanded to 15 volumes in 1947, and renamed Britannica Junior Encyclopædia in 1963. It was taken off the market after the 1984 printing. A British Children's Britannica edited by John Armitage
8300-496: The same. In people born after 1900, the death rate of 50- to 70-year-old men was double that of women of the same age. Men may be more vulnerable to cardiovascular disease than women, but this susceptibility was evident only after deaths from other causes, such as infections, started to decline. Most of the difference in life expectancy between the sexes is accounted for by differences in the rate of death by cardiovascular diseases among persons aged 50–70. The heritability of lifespan
8400-642: The scholarship of our American encyclopaedias. As of 2007 in the 15th edition of Britannica , Dale Hoiberg , a sinologist , was listed as Britannica 's Senior Vice President and editor-in-chief. Among his predecessors as editors-in-chief were Hugh Chisholm (1902–1924), James Louis Garvin (1926–1932), Franklin Henry Hooper (1932–1938), Walter Yust (1938–1960), Harry Ashmore (1960–1963), Warren E. Preece (1964–1968, 1969–1975), Sir William Haley (1968–1969), Philip W. Goetz (1979–1991), and Robert McHenry (1992–1997). As of 2007 Anita Wolff
8500-399: The smallest premature babies (those under 2 pounds (910 grams)), females have a higher survival rate. At the other extreme, about 90% of individuals aged 110 are female. The difference in life expectancy between men and women in the United States dropped from 7.8 years in 1979 to 5.3 years in 2005, with women expected to live to age 80.1 in 2005. Data from the United Kingdom shows
8600-726: The staff members, advisors, and contributors to all three parts of the Britannica . Taken together, the Micropædia and Macropædia comprise roughly 40 million words and 24,000 images. The two-volume index has 2,350 pages, listing the 228,274 topics covered in the Britannica , together with 474,675 subentries under those topics. The Britannica generally prefers British spelling over American ; for example, it uses colour (not color ), centre (not center ), and encyclopaedia (not encyclopedia ). There are some exceptions to this rule, such as defense rather than defence . Common alternative spellings are provided with cross-references such as "Color: see Colour." Since 1936,
8700-569: The strategy pioneered by former CEO Elkan Harrison Powell in the mid-1930s. In the fall of 2017, Karthik Krishnan was appointed global chief executive officer of the Encyclopædia Britannica Group. Krishnan brought a varied perspective to the role based on several high-level positions in digital media, including RELX (formerly known as Reed Elsevier, and one of the constituents of the FTSE 100 Index) and Rodale, in which he
8800-460: The study. Demography often contrasts cohort perspectives and period perspectives . For instance, the total cohort fertility rate is an index of the average completed family size for cohorts of women, but since it can only be known for women who have finished child-bearing, it cannot be measured for currently fertile women. It can be calculated as the sum of the cohort's age-specific fertility rates that obtain as it ages through time. In contrast,
8900-454: The total period fertility rate uses current age-specific fertility rates to calculate the completed family size for a notional woman, were she to experience these fertility rates through her life. A study on a cohort is a cohort study . Two important types of cohort studies are: Encyclop%C3%A6dia Britannica This is an accepted version of this page The Encyclopædia Britannica ( Latin for 'British Encyclopaedia')
9000-467: The unsigned Micropædia articles. In January 1996, the Britannica was purchased from the Benton Foundation by billionaire Swiss financier Jacqui Safra , who serves as its current chair of the board. In 1997, Don Yannias, a long-time associate and investment advisor of Safra, became CEO of Encyclopædia Britannica, Incorporated. In 1999, a new company, Britannica.com Incorporated ,
9100-685: The watchword of its first edition in 1768. As the Britannica is a general encyclopaedia, it does not seek to compete with specialized encyclopaedias such as the Encyclopaedia of Mathematics or the Dictionary of the Middle Ages , which can devote much more space to their chosen topics. In its first years, the Britannica 's main competitor was the general encyclopaedia of Ephraim Chambers and, soon thereafter, Rees's Cyclopædia and Coleridge's Encyclopædia Metropolitana . In
9200-483: The world, females have a higher life expectancy at age 60 than males. Of 72 selected causes of death, only 6 yielded greater female than male age-adjusted death rates in 1998 in the United States. Except for birds, for almost all of the animal species studied, males have higher mortality than females. Evidence suggests that the sex mortality differential in people is due to both biological/genetic and environmental/behavioral risk and protective factors. One recent suggestion
9300-473: Was created to develop digital versions of the Britannica ; Yannias assumed the role of CEO in the new company, while his former position at the parent company remained vacant for two years. Yannias' tenure at Britannica.com Incorporated was marked by missteps, considerable lay-offs, and financial losses. In 2001, Yannias was replaced by Ilan Yeshua , who reunited the leadership of the two companies. Yannias later returned to investment management, but remains on
9400-500: Was also available as a Firefox extension but this was taken down due to a code review issue. The print version of the Britannica has 4,411 contributors, many eminent in their fields, such as Nobel laureate economist Milton Friedman , astronomer Carl Sagan , and surgeon Michael DeBakey . Roughly a quarter of the contributors are deceased, some as long ago as 1947 ( Alfred North Whitehead ), while another quarter are retired or emeritus . Most (approximately 98%) contribute to only
9500-404: Was done in the 1660s by John Graunt , Christiaan Huygens , and Lodewijck Huygens . The longest verified lifespan for any human is that of Frenchwoman Jeanne Calment , who is verified as having lived to age 122 years, 164 days, between 21 February 1875 and 4 August 1997. This is referred to as the " maximum life span ", which is the upper boundary of life, the maximum number of years any human
9600-793: Was found that high-quality early-stage childhood education had positive effects on health. Researchers discovered this by analyzing the results of the Carolina Abecedarian Project , finding that the disadvantaged children who were randomly assigned to treatment had lower instances of risk factors for cardiovascular and metabolic diseases in their mid-30s. Various species of plants and animals, including humans, have different lifespans. Evolutionary theory states that organisms which—by virtue of their defenses or lifestyle—live for long periods and avoid accidents, disease, predation, etc. are likely to have genes that code for slow aging, which often translates to good cellular repair. One theory
9700-672: Was issued in London in 1960. Its contents were determined largely by the eleven-plus standardized tests given in Britain. Britannica introduced the Children's Britannica to the US market in 1988, aimed at ages seven to 14. In 1961, a 16-volume Young Children's Encyclopaedia was issued for children just learning to read. My First Britannica is aimed at children ages six to 12, and the Britannica Discovery Library
9800-518: Was listed as the Deputy Editor and Theodore Pappas as Executive Editor. Prior Executive Editors include John V. Dodge (1950–1964) and Philip W. Goetz. Paul T. Armstrong remains the longest working employee of Encyclopædia Britannica. He began his career there in 1934, eventually earning the positions of treasurer, vice president, and chief financial officer in his 58 years with the company, before retiring in 1992. The 2007 editorial staff of
9900-400: Was responsible for "driving business and cultural transformation and accelerating growth". Taking the reins of the company as it was preparing to mark its 250th anniversary and define the next phase of its digital strategy for consumers and K–12 schools, Krishnan launched a series of new initiatives in his first year. First was Britannica Insights, a free, downloadable software extension to
10000-466: Was significantly more expensive than its competitors. Since the early 1990s, the Britannica has faced new challenges from digital information sources. The Internet, facilitated by the development of search engines , has grown into a common source of information for many people, and provides easy access to reliable original sources and expert opinions, thanks in part to initiatives such as Google Books , MIT 's release of its educational materials and
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