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Yahoo! Answers
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Yahoo! Answers
A screenshot of a Yahoo! Answers question.
Type of site
Collaboration
Available in
Chinese, English, French, German, Indonesian, Italian, Japanese, Korean, Portuguese, Spanish, Thai, Vietnamese
Website
answers.yahoo.com
Commercial
No
Launched
June 28, 2005; 12 years ago (2005-06-28)
Current status
Active
Yahoo! Answers is a community-driven question-and-answer (Q&A) website or a knowledge market from Yahoo!, that allows users to both submit questions to be answered and answer questions asked by other users.
Contents
[hide]
1 History
2 Site operation
3 Level table
4 Badges
4.1 Top Contributor
4.2 Staff
4.3 Official
4.4 Knowledge Partners
5 Academic studies
6 Quality of answers
7 Promotions and events
7.1 Yamster
7.2 Special guests
8 Site statistics
9 In popular media
10 See also
11 References
12 Further reading
13 External links
History[edit]
The website Yahoo! was officially incorporated on March 2, 1995, and was created by Jerry Yang and David Filo. The website began as a search directory for various websites, and soon grew into an established Internet resource that features the "Yahoo! Answers" platform.[1] Yahoo! Answers was launched on June 28, 2005, while in internal alpha testing by Director of Engineering, Ofer Shaked.[2][3][4] Yahoo! Answers was launched to the general public while in beta testing on December 8, 2005,[5][6] which lasted until May 14, 2006. Yahoo! Answers was finally incorporated for general availability on May 15, 2006.[7]
Yahoo! Answers was created to replace Ask Yahoo!, Yahoo!'s former Q&A platform which was discontinued in March 2006.[8] The site gives members the chance to earn points as a way to encourage participation and is based on Naver's Knowledge iN. Yahoo! Answers is available in 12 languages, but several Asian sites operate a different platform which allows for non-Latin characters. The platform is known as Yahoo! Chiebukuro (Yahoo!知恵袋) in Japan[9] and as Yahoo! Knowledge in Korea, Taiwan, China, and Hong Kong.[citation needed] An Arabic language Q&A platform called Seen Jeem is available through the Yahoo! subsidiary Maktoob.
On December 8, 2016, Yahoo! released an app for the platform called Yahoo! Answers Now (formally known as Yahoo! Hive) for iOS and Android.[10][11][12][13][14]
The number of poorly formed questions and inaccurate answers has made the site a target of ridicule.[15][16]
Site operation[edit]
Yahoo! Answers allows any questions that do not violate Yahoo! Answers community guidelines.[17] To encourage good answers, helpful participants are occasionally featured on the Yahoo! Answers Blog. Though the service itself is free, the contents of the answers are owned by the respective users – while Yahoo! maintains a non-exclusive royalty-free worldwide right to publish the information.[18] Chat is explicitly forbidden in the Community Guidelines, although categories like Politics and Religion & Spirituality are mostly opinion.[19] Users may also choose to reveal their Yahoo! Messenger ID on their Answers profile page.
Misuse of Yahoo! Answers is handled by a user moderation system, where users report posts that are in breach of guidelines or the Terms of Service. Posts are removed if they receive sufficient weight of trusted reports (reports from users with a reliable reporting history). Deletion may be appealed: an unsuccessful appeal receives a 10-point penalty; a successful one reinstates the post and reduces the 'trust rating' (reporting power) of the reporter. If a user receives a large number of violations in a relatively short amount of time or a very serious violation, it can cause the abuser's account to be suspended. In extreme, but rare cases (for a Terms of Service violation), the abuser's entire Yahoo! ID will be suddenly deactivated without warning.
To open an account, a user needs a Yahoo! ID but can use any name as identification on Yahoo! Answers. A user can be represented by a picture from various internet avatar sites or a user-made graphic uploaded to replace their default Yahoo graphic. Yahoo! Avatars was discontinued in 2012. When answering a question, a user can search Yahoo! or Wikipedia, or any source of information that the user wishes, as long as they mention their source.
Questions are initially open to answers for four days. However, the asker can choose to pick a best answer for the question after a minimum of one hour. However, comments and answers can still be posted after this time.[20] To ask a question, one has to have a Yahoo! account with a positive score balance of five points or more.
The points system is weighted to encourage users to answer questions and to limit spam questions. There are also levels (with point thresholds), which give more site access.[21] Points and levels have no real world value, cannot be traded, and serve only to indicate how active a user has been on the site. A notable downside to the points/level system is that it encourages people to answer questions even when they do not have a suitable answer to give to gain points. Users also receive ten points for contributing the "Best Answer" which is selected by the question's asker. The voting function, which allowed users to vote for the answer they considered best, was discontinued in April 2014.
In addition to points awarded for activity,[21] Yahoo! Answers staff may also award extra points if they are impressed with a user's contributions.[22] The Yahoo! Answers community manager has stated that "power users" who defend the company should be thanked and rewarded.[23]
Level table[edit]
Level 1
Level 2
Level 3
Level 4
Level 5
Level 6
Level 7
Points 1–249 250–999 1,000–2,499 2,500–4,999 5,000–9,999 10,000–24,999 25,000+
Questions 5 10 15 20 20 20 20
Answers 20 80 120 160 160 160 160
Commentaries 10 20 30 40 40 40 40
Stars 10 100 100 100 100 100 100
Evaluation permission No Yes Yes Yes Yes Yes Yes
Note: All limitations are per day.
Users begin on level 1 and receive 100 free points. Prior to this, they began on level 0, could only answer one question, and then were promoted to level 1.
Before April 20, 2012, users levels 5 and above could give an unlimited amount of questions, answers, and comments. Yahoo! Answers established an upper limit to curb spam and unproductive answers.[24] Before April 2014 users were also able to vote for a best answer if the asker did not choose one, but this was discontinued.
Badges[edit]
Top Contributor[edit]
The point system ostensibly encourages users to answer as many questions as they possibly can, up to their daily limit. Once a user achieves and maintains a certain minimum number of such contributions (See Note*, further...), they may receive an orange "badge" under the name of their avatar, naming the user a Top Contributor (TC). Users can lose this badge if they do not maintain their level of participation.[25] Once a user becomes a "Top Contributor" in any category, the badge appears in all answers, questions, and comments by the user, regardless of category. A user can be a Top Contributor in a maximum of 3 categories.[25] The list of Top contributors is updated every Monday.[25] Although Yahoo! Answers staff has kept secret the conditions of becoming a TC, many theories exist among users, for example:
Maintaining a weekly (mystery) "quota" of answers in the category.
User wanting to become a TC must have more than or equal to 12% Best answers.
User should be at least on level 2, although there have been claims[citation needed] that first-level users with TC Badge have been seen.
User should concentrate only on one particular category to become a Top Contributor for that category.
Out of these, none have an official status. This feature began March 8, 2007.
Staff[edit]
Badge is seen under the name staff members of Yahoo! Answers.[26]
Official[edit]
This type of badge is found on the name of celebrities (like mentioned above) and government departments like the health department.[26]
Knowledge Partners[edit]
These badges are found under the name of the companies or organizations who share their personal knowledge and experience with the members of Yahoo! Answers.[26]
Academic studies[edit]
A number of studies have looked at the structure of the community and the interaction between askers and responders. Studies of user typology on the site have revealed that some users answer from personal knowledge – "specialists" – while others use external sources to construct answers – "synthesists", with synthesists tending to accumulate more reward points.[27] Adamic et al. looked at the ego networks of users and showed that it is possible to distinguish "answer people" from "discussion people" with the former found in specialist categories for factual information, such as mathematics and the latter more common in general interest categories, such as marriage and wrestling. They also show that answer length is a good predictor of "best answer" choice.[28] Kim and Oh looked at the comments given by users on choosing best answers and showed that content completeness, solution feasibility and personal agreement/confirmation were the most significant criteria.[29]
Quality of answers[edit]
Researchers found that questions seeking factual information received few answers and that the knowledge on Yahoo! Answers is not very deep.[19]
Despite the presence of experts, academics and other researchers, Yahoo! Answers' base consists of a much more general group; hence, it has been criticized for the large number of dubious questions, such as "how is babby formed how girl get pragnent" [sic], which sparked an Internet meme.
This "Internet language" of incorrect spelling and improper grammar also contributes to Yahoo! Answers' reputation of being a source of entertainment rather than a fact based question and answer platform,[30][31] and for the reliability, validity, and relevance of its answers. A 2008 study found that Yahoo! Answers is suboptimal for questions requiring factual answers and that the quality decreases as the number of users increases.[32] One journalist observed that the structure Yahoo! Answers provides, particularly the persistence of inaccuracies, the inability to correct them, and a point structure that rewards participation more readily than accuracy, all indicate that the site is oriented towards encouraging use of the site, not offering accurate answers to questions.[33] The number of poorly formed questions and inaccurate answers has made the site a target of ridicule.[15][16] Likewise, posts on many Internet forums and Yahoo! Answers itself indicate that Yahoo! Answers attracts a large number of trolls.
The site does not have a system that filters the correct answers from the incorrect answers.[34] At one time, the community could vote for the best answer among the posted answers; but that option was disabled in March 2014.[35] For most of the life of Yahoo! Answers, once the "best answer" was chosen, there was no way to add more answers nor to improve or challenge the best answer chosen by the question asker; there is a display of thumbs down or thumbs up for each answer, but viewers cannot vote. In April 2014, this was changed to allow for additional answers after a best answer is chosen, but the best answer can never be changed. Also, while "best answers" can be briefly commented upon, the comment is not visible by default and is hence hardly read.[citation needed] (Even the user who posts the question isn't notified, before or after the best answer is picked, about a comment on the question or on the best answer.) If the best answer chosen is wrong or contains problematic information, the only chance to give a better (or correct) answer will be the next time the same question is asked. The older answer will likely get higher priority in search engines. Any new answer will most probably not be seen by any original questioner.[original research?]
Promotions and events[edit]
Yamster[edit]
The Yahoo! Answers green smiley.
The official Yahoo! Answers mascot is a cartoon hamster called Yamster. Yamster is a combination, or portmanteau, of the words "Yahoo" and "hamster". The mascot is also used as an avatar for Yahoo! Answers staff.[36]
During beta testing of Yahoo! Answers in 2005, the Director of Product Management would use a Gemmy Kung Fu Hamster to summon employees to meetings. The toy was a battery-operated, dancing, musical plush hamster clothed in a karate uniform. A Yahoo! Answers employee selected a photo of the toy as the staff avatar.[37] A user then questioned the potential trademark/copyright infringement of using such an avatar. At that time, the photo was replaced with the Yahoo! Answers green smiley face. At the beginning of 2006, the green smiley face was replaced by the cartoon Yamster clad in a karate uniform.[38] As of November 2009[update], the history of Yamster, complete with photos of the toy, was available on the Yahoo! Answers Team Vietnam blog.[39]
Special guests[edit]
Several celebrities and notables have appeared on Yahoo! Answers to ask questions. These users have an "official" badge below their avatar and on their profile page. During the 2008 U.S. Presidential campaign, Hillary Clinton, John McCain, Barack Obama, and Mitt Romney posted questions on Yahoo! Answers, in addition to YouTube.[40] In an awareness campaign, "UNICEF Up Close 2007", nine UNICEF ambassadors asked questions.[41][42] The launch of Answers on Yahoo! India included a question from A. P. J. Abdul Kalam, the President of India at that time.[43] Other guests have included international leaders (Queen Rania of Jordan,[44] candidate for United Nations Secretary-General Shashi Tharoor[45]), Nobel Peace Prize laureates (Al Gore,[46][47] Muhammad Yunus[48]) and other international activists (Bono,[46] Jean-Michel Cousteau[49]), intellectuals (Stephen Hawking,[46] Marilyn vos Savant[47]), and numerous other celebrities.
Site statistics[edit]
Yahoo! used comScore statistics in December 2006 to proclaim Yahoo! Answers "the leading Q&A site on the web".[50] Currently Yahoo! Answers is ranked as the second most popular Q&A site on the web by comScore.[51][52] The slogan "The world's leading Q&A site" has since been adopted by Answers.com.
In 2009, Yahoo! Answers staff claimed 200 million users worldwide[53] and 15 million users visiting daily.[54] Google Trends has reported around 4 million unique visitors (Global) daily.[55] In January 2010, the web analytics website Quantcast reported 24 million active users (US) per month; in November 2015, that had fallen by 77% to 5.6 million.[56] Quantcast traffic statistics for Yahoo! Answers, January 2010:
24,201,619 people per month (US)
62,171,200 visits per month (US)
For January 1–30, 2015:
11,273,839 people per month (US)
For October 31 – November 29, 2015:
5,555,080 people per month (US)
For December 1 – December 30, 2015:
4,546,016 people per month (US)
Google Ad Planner traffic statistics for Yahoo! Answers, December 2009:[57]
26,000,000 unique visitors (users) (US)
110,000,000 total visits (US)
Compete Site Analytics traffic statistics for Yahoo! Answers, December 2009:[58]
33,090,163 unique visitors (US)
64,928,634 visits (US)
Yahoo! Answers represents between 1.03%[59] to 1.7%[60] of Yahoo! traffic.
In popular media[edit]
The comedy/advice podcast My Brother, My Brother and Me features a reoccurring segment in which co-host Griffin McElroy selects and reads a particularly humorous or outrageous question from Yahoo! Answers. The hosts then discuss and attempt to answer the question, to comedic effect.[61] [62]
The Internet troll Ken M is a regular user on Yahoo! Answers, posting comments that confound and annoy other users. There are several communities on social media sites such as Reddit and Facebook dedicated to observing his antics, especially on Yahoo! Answers.[63][64] Ken was named as one of Time's most influential people online in 2016.[65]
See also[edit]
List of question-and-answer websites
Ask MetaFilter
Askalo
Askville
Blurtit
GirlsAskGuys
Google Answers
Q&A software
Hunch
Knowledge Search
LinkedIn Answers
Quora
Stack Exchange
Wiki Answers
References[edit]
Jump up ^ Mccullough, Brian. "On the 20th Anniversary – The History of Yahoo's Founding". Internet History Podcast.
Jump up ^ "First/oldest Y!A account - Director of Engineering, Ofer Shaked's Yahoo! Answers account, created on June 28, 2005". Yahoo! Answers. 2005-06-28. Retrieved 2016-03-29.
Jump up ^ "SiliconBeat: Yahoo Answers". SiliconBeat. 2005-12-07. Retrieved 2016-04-01.
Jump up ^ "The Birth of Yahoo Answers - Search Engine Watch". Search Engine Watch. 2005-12-07. Retrieved 2016-04-01.
Jump up ^ "Yahoo launches Q&A service - CNET News.com". CNET. 2005-12-07. Archived from the original on December 10, 2005. Retrieved 2016-02-28.
Jump up ^ "Yahoo! Answers - Home on December 10, 2005". Wayback Machine. December 10, 2005. Archived from the original on December 10, 2005. Retrieved February 28, 2016.
Jump up ^ "Yahoo - Yahoo! Search Leverages Human Knowledge From Yahoo! Answers to Improve Web Search; Yahoo! Answers Surpasses 10 Million Answers to Everyday Questions From Real People". Yahoo! Investor. 2006-05-15. Retrieved 2016-02-28.
Jump up ^ Schwartz, Barry (December 13, 2006). "Yahoo Answers Birthday: One Year Old". Search Engine Land. Retrieved August 22, 2012.
Jump up ^ "Yahoo! Chiebukuro Website". Retrieved August 22, 2012.
Jump up ^ "Yahoo Answers Now on the App Store". iTunes. Retrieved 2016-12-12.
Jump up ^ "Yahoo Answers Now - Android Apps on Google Play". Google Play. Retrieved 2016-12-12.
Jump up ^ "Yahoo Answers Now is a standalone app for iOS". Engadget. 2016-11-29. Retrieved 2016-12-12.
Jump up ^ "Yahoo officially launches its Yahoo Answers Q&A mobile app - VentureBeat". VentureBeat. 2016-12-08. Retrieved 2016-12-12.
Jump up ^ "Yahoo Answers makes its official mobile debut - TechCrunch". TechCrunch. 2016-12-09. Retrieved 2016-12-12.
^ Jump up to: a b Raphael, J. R. (December 17, 2009). "The 20 Dumbest Questions on Yahoo Answers". PC World. Retrieved May 24, 2010.
^ Jump up to: a b Ahmed, Murad (January 3, 2009). "Ask a silly question.." The Times. London. Retrieved May 24, 2010.
Jump up ^ "Community guidelines". Yahoo! Answers. Retrieved April 20, 2012.
Jump up ^ "Yahoo! Terms of Service". Yahoo! Terms. Retrieved August 22, 2012. 9) Content submitted or made available for inclusion on the Yahoo! Services: Yahoo! does not claim ownership of Content you submit or make available for inclusion on the Yahoo! Services. However, with respect to Content you submit or make available for inclusion on publicly accessible areas of the Yahoo! Services, you grant Yahoo! the following worldwide, royalty-free and non-exclusive license(s), as applicable
^ Jump up to: a b Moore, Nicole Casal (April 21, 2008). "Users of Yahoo Answers seek advice, opinion, expertise". University of Michigan News Service. Ann Arbor, Michigan. Retrieved August 22, 2012.
Jump up ^ "What if my question doesn't receive any answers?". Yahoo! Help. Retrieved August 22, 2012.
^ Jump up to: a b "Yahoo! Answers – Point System". Yahoo! Answers. Retrieved August 22, 2012.
Jump up ^ "A person in my category has -9,000 points this week. (Yes, that's a minus.) Someone else has -22% Best Answers. (Also a minus)". Yahoo! Answers Suggestion Board. Archived from the original on January 15, 2010. Retrieved August 22, 2012. Sometimes when we [Yahoo!Answers employees] are impressed with a user's answer quality or overall contribution to make Answers a better place, we award extra points as a mark of encouragement.
Jump up ^ "Managing the Mob: What to do when things go wrong". Socialtext. Archived from the original on November 22, 2009. Retrieved August 22, 2012.
Jump up ^ "Limitations on Level 5, 6 and 7 Users". Yahoo! Answers Blog. April 18, 2012. Retrieved 22 August 2012.
^ Jump up to: a b c "What is a Top Contributor?". Yahoo! Answers. Retrieved August 22, 2012.
^ Jump up to: a b c "What do the different badges on Yahoo! Answers mean?". Yahoo!Answers. December 7, 2009. Archived from the original on November 12, 2010.
Jump up ^ Gazan, R.; et al. (2006). "Specialists and Synthesists in a Question Answering Community". 69th Annual Meeting of the American Society for Information Science and Technology (ASIST), Austin (US), 3–8 November 2006. Richard B. Hill. CiteSeerX 10.1.1.124.6014  . Missing or empty |url= (help); |access-date= requires |url= (help)
Jump up ^ Adamic, L.; et al. (2008). "Knowledge Sharing and Yahoo Answers: Everyone Knows Something". WWW 2008 / Refereed Track: Social Networks & Web 2.0 -Analysis of Social Networks & Online Interaction. Retrieved 2017-12-05.
Jump up ^ Kim, S.; Oh, S. (2009). "Users' relevance criteria for evaluating answers in a social Q&A site". Journal of the American Society for Information Science and Technology. 60 (4): 716. doi:10.1002/asi.21026.
Jump up ^ "Stet". The New York Times. July 20, 2008. Retrieved April 26, 2017.
Jump up ^ Modine, Austin (June 9, 2009). "Wolfram Alpha to venture beyond boron nucleus". The Register. Southport, England: Situation Publishing. Retrieved January 24, 2011.
Jump up ^ Liu, Yandong; Agichtein, Eugene (2008). "On the Evolution of the Yahoo! Answers QA Community" (PDF).
Jump up ^ Liebenluft, Jacob (December 7, 2007). "A Librarian's Worst Nightmare: Yahoo! Answers, where 120 million users can be wrong". Slate. Retrieved August 23, 2011.
Jump up ^ Angwin, Julia (December 23, 2008). "Looking for a Few Good Answers Online". WSJ.
Jump up ^ "Important Changes to Answers". Yahoo! Answers official blog. March 20, 2014. Retrieved January 22, 2016.
Jump up ^ "Yahoo! Answers Team's Profile". Answers.yahoo.com. Retrieved April 20, 2012.
Jump up ^ "MyThings – View Item: KungFu Hamster". Archived from the original on November 10, 2009.
Jump up ^ "What is the history of the Yahoo! Answers Hamster?". Answers.yahoo.com. Retrieved April 20, 2012.
Jump up ^ "Y! Answers _ Yamster". Archived from the original on November 17, 2009.
Jump up ^ Mills, Elinor (April 11, 2007). "Presidential candidates to appear on YouTube". CNET News. Retrieved April 10, 2009.
Jump up ^ "Yahoo Answers Unicef And Widgets Vista". WebProNews. January 30, 2007. Retrieved April 10, 2009.
Jump up ^ "UNICEF Up Close 2007". 2007. Retrieved April 10, 2009.
Jump up ^ "`Yahoo! Answers' launched". The Hindu Business Line. The Hindu Group. January 14, 2007. Retrieved April 10, 2009.
Jump up ^ "Queen Rania of Jordan's Activity – Yahoo! Answers". Answers.yahoo.com. Retrieved April 20, 2012.
Jump up ^ "Shashi Tharoor's Activity – Yahoo! Answers". Answers.yahoo.com. February 1, 2007. Retrieved April 20, 2012.
^ Jump up to: a b c Sample, Ian (July 8, 2006). "Hawking turns to Yahoo for answers to his big question". The Guardian. Retrieved April 11, 2009.
^ Jump up to: a b Herman, Michele (June 23, 2006). "Answer Al Gore's Question, Win a Prius". Extra Helping. School Library Journal. Retrieved April 11, 2009.
Jump up ^ "How can you help to create a poverty-free world? – Yahoo! Answers". Answers.yahoo.com. December 6, 2006. Retrieved April 20, 2012.
Jump up ^ "Jean-Michel Cousteau's Activity – Yahoo! Answers". Answers.yahoo.com. June 7, 2007. Retrieved April 20, 2012.
Jump up ^ "Yahoo! Answers Celebrates One Year of Knowledge and Success as Poll Reveals Use and Influence of Q&A Sites" (Press release). Business Wire. December 13, 2006. Archived from the original on November 16, 2009. Retrieved November 15, 2009.
Jump up ^ "Who's Scorched Up comScore In September, You Ask?". October 15, 2009. Retrieved September 18, 2010.
Jump up ^ "Answers.com Announces September comScore Rank of No. 13, up from No. 18 in August" (Press release). Business Wire. October 15, 2009. Retrieved November 15, 2009.
Jump up ^ "Yahoo! Answers hits 200 million visitors – December 14, 2009". Yanswersblog.com. December 14, 2009. Retrieved April 20, 2012.
Jump up ^ "Did you know? – October 5, 2009". Yanswersblog.com. October 5, 2009. Retrieved April 20, 2012.
Jump up ^ "Google Trends for Yahoo! Answers". Google. Retrieved April 20, 2012.
Jump up ^ "Quantcast profile for Yahoo! Answers". Quantcast.com. Retrieved April 20, 2012.
Jump up ^ "Site profile for Yahoo! Answers". Google. Archived from the original on January 4, 2012. Retrieved April 20, 2012.
Jump up ^ "Site Profile for answers.yahoo.com". Site Analytics. October 26, 2011. Retrieved April 20, 2012.
Jump up ^ Hopkins, Heather (March 5, 2009). "Yahoo! Mail More than One Third of Yahoo! Traffic". Experian Hitwise blogs. Retrieved April 20, 2012.
Jump up ^ "Yahoo.com site info". Alexa.com. Retrieved August 22, 2012.
Jump up ^ "My Brother, My Brother, and Me". Maximum Fun. Retrieved 8 February 2017.
Jump up ^ Lavender, Dave (8 November 2010). "McElroy brothers find success with podcast". The Herald-Dispatch. Retrieved 8 February 2017.
Jump up ^ "Ken M dedicated Reddit site". Reddit.com. Retrieved 28 March 2017.
Jump up ^ "Ken M official Facebook page". Facebook.com. Retrieved 28 March 2017.
Jump up ^ "Independent article on Ken M". independent.co.uk. Retrieved 28 March 2017.
Further reading[edit]
Gomes, Lee (August 23, 2006). "Portals: Success, greed in the new economy of web point payouts". Pittsburgh Post-Gazette. The Wall Street Journal. Archived from the original on March 6, 2008.
External links[edit]
Official website
Quicken Support Phone Number
Answers architect
Yahoo! Answers Suggestion Board
Answers API
Ask Yahoo!, Yahoo!'s former Q&A site, now merged with Answers
Python wrapper over Answers API
Introducing the new Yahoo! Answers (Tumblr announcement)
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Trevi Fountain
From Wikipedia, the free encyclopedia
Jump to: navigation, search
Trevi Fountain
Italian: Fontana di Trevi
Artist
Nicola Salvi
Year
1762 (1762)
Type
Public fountain
Medium
Stone
Dimensions
26.3 m × 49.15 m (86 ft × 161.3 ft)
Location
Trevi, Rome, Italy
Coordinates
41°54′3.15″N 12°28′59.4″E / 41.9008750°N 12.483167°E / 41.9008750; 12.483167Coordinates: 41°54′3.15″N 12°28′59.4″E / 41.9008750°N 12.483167°E / 41.9008750; 12.483167
The Trevi Fountain (Italian: Fontana di Trevi) is a fountain in the Trevi district in Rome, Italy, designed by Italian architect Nicola Salvi and completed by Pietro Bracci. Standing 26.3 metres (86 ft) high and 49.15 metres (161.3 ft) wide,[1] it is the largest Baroque fountain in the city and one of the most famous fountains in the world. The fountain has appeared in several notable films, including Federico Fellini's La Dolce Vita and the eponymous Three Coins in the Fountain.
Contents
[hide]
1 History before 1629
2 Commission, construction, and design
3 Restoration
4 Iconography
4.1 Coin throwing
5 Trivia
6 See also
7 References
8 External links
History before 1629[edit]
Trevi Fountain in Rome, Italy.
The fountain at the junction of three roads (tre vie)[2] marks the terminal point[3] of the "modern" Acqua Vergine, the revived Aqua Virgo, one of the aqueducts that supplied water to ancient Rome. In 19 BC, supposedly with the help of a virgin, Roman technicians located a source of pure water some 13 km (8.1 mi) from the city. (This scene is presented on the present fountain's façade.) However, the eventual indirect route of the aqueduct made its length some 22 km (14 mi). This Aqua Virgo led the water into the Baths of Agrippa. It served Rome for more than 400 years.[4]
Commission, construction, and design[edit]
In 1629 Pope Urban VIII, finding the earlier fountain insufficiently dramatic, asked Gian Lorenzo Bernini to sketch possible renovations, but the project was abandoned when the pope died. Though Bernini's project was never constructed, there are many Bernini touches in the fountain as it exists today. An early, influential model by Pietro da Cortona, preserved in the Albertina, Vienna, also exists, as do various early 18th century sketches, most unsigned, as well as a project attributed to Nicola Michetti[5] one attributed to Ferdinando Fuga[6] and a French design by Edme Bouchardon.[7]
Trevi Fountain at night
Competitions had become the rage during the Baroque era to design buildings, fountains and even the Spanish Steps. In 1730 Pope Clement XII organized a contest in which Nicola Salvi initially lost to Alessandro Galilei – but due to the outcry in Rome over the fact that a Florentine won, Salvi was awarded the commission anyway.[8] Work began in 1732 and the fountain was completed in 1762, long after Salvi's death, when Pietro Bracci's Oceanus (god of all water) was set in the central niche.
Salvi died in 1751 with his work half finished, but he had made sure a stubborn barber's unsightly sign would not spoil the ensemble, hiding it behind a sculpted vase, called by Romans the asso di coppe, the "Ace of Cups".
The Trevi Fountain was finished in 1762 by Giuseppe Pannini, who substituted the present allegories for planned sculptures of Agrippa and "Trivia", the Roman virgin. It was officially opened and inaugurated on May 22 by Pope Clement XIII.
The majority of the piece is made from Travertine stone, quarried near Tivoli, about 35 kilometres (22 miles) east of Rome.[9]
Sculptures at night
Restoration[edit]
Trevi Fountain papal coat of arms
Trevi Fountain as viewed from the side
The fountain was refurbished in 1998; the stonework was scrubbed and all cracks and other areas of deterioration were repaired by skilled artisans and the fountain was equipped with recirculating pumps.
In January 2013, it was announced that the Italian fashion company Fendi would sponsor a 20-month, 2.2-million-euro restoration of the fountain; it was to be the most thorough restoration in the fountain's history.[10]
Restoration work began in June 2014 and was completed in November 2015. The fountain was reopened with an official ceremony on the evening of November 3, 2015. The restoration included the installation of more than 100 LED lights to improve the nighttime illumination of the fountain. [11] [12] [13]
Iconography[edit]
The backdrop for the fountain is the Palazzo Poli, given a new façade with a giant order of Corinthian pilasters that link the two main stories. Taming of the waters is the theme of the gigantic scheme that tumbles forward, mixing water and rockwork, and filling the small square. Tritons guide Oceanus' shell chariot, taming hippocamps.
In the centre a robustly-modelled triumphal arch is superimposed on the palazzo façade. The centre niche or exedra framing Oceanus has free-standing columns for maximal light and shade. In the niches flanking Oceanus, Abundance spills water from her urn and Salubrity holds a cup from which a snake drinks. Above, bas reliefs illustrate the Roman origin of the aqueducts.
The tritons and horses provide symmetrical balance, with the maximum contrast in their mood and poses[citation needed] (by 1730, rococo was already in full bloom in France and Germany).
Coin throwing[edit]
Coins are purportedly meant to be thrown using the right hand over the left shoulder. This was the theme of 1954's Three Coins in the Fountain and the Academy Award-winning song by that name which introduced the picture.
An estimated 3,000 Euros are thrown into the fountain each day.[14] In 2016, an estimated US $1.5 million was thrown into the fountain.[15] The money has been used to subsidise a supermarket for Rome's needy;[14] however, there are regular attempts to steal coins from the fountain although it is illegal to do so.[14][16][17]
Trivia[edit]
In 1973, Italian National Postal Service dedicated a postage stamp to the Trevi Fountain.[citation needed]
See also[edit]
List of fountains in Rome
Fountains of Rome
References[edit]
Citations
Jump up ^ "Trevi Fountain". TreviFountain.net.
Jump up ^ Though other etymologies have been suggested, this is the straightforward modern etymology adopted by Pinto 1986 and others.
Jump up ^ The technical Italian term for such a "terminal fountain" is a ("display"): Peter J. Aicher, "Terminal Display Fountains ("Mostre") and the Aqueducts of Ancient Rome" Phoenix 47.4 (Winter 1993:339–352).
Jump up ^ Pintochs.yes I and II.
Jump up ^ John A. Pinto, "An Early Project by Nicola Michetti for the Trevi Fountain" The Burlington Magazine 119 No. 897 (December 1977:853–857).
Jump up ^ Pinto, John; Elisabeth Kieven (December 1983). "An Early Project by Ferdinando Fuga for the Trevi Fountain in Rome". The Burlington Magazine. 125: 746–749, 751.
Jump up ^ Pinto 1986. Bouchardon's drawing is conserved in the Musée Vivènal, Compiègne.
Jump up ^ Gross, Hanns (1990). Rome in the Age of Enlightenment: the Post-Tridentine syndrome and the ancient regime. New York: Cambridge University Press. p. 28. ISBN 0-521-37211-9.
Jump up ^ "The Trevi Fountain – The most beautiful fountain in the world". Retrieved 23 February 2014.
Jump up ^ Pullella, Philip (29 January 2013). "Rome Trevi Fountain, symbol of Dolce Vita, to get big facelift". Reuters. Retrieved 29 January 2013.
Jump up ^ "Torna l'acqua a Fontana di Trevi, dopo il restauro firmato Fendi". Roma - La Repubblica. 3 November 2015.
Jump up ^ "La Fontana di Trevi torna all'antico splendore dopo il restauro". rainews. 11 March 2015.
Jump up ^ "La Fontana di Trevi, applauso e flash salutano il ritorno dell'acqua". ANSA.it.
^ Jump up to: a b c "Trevi coins to fund food for poor". BBC News. 26 November 2006. Retrieved 18 January 2010.
Jump up ^ "Rome’s Trevi Fountain Holds Nearly $1.5 Million in Loose Change". NBC. 13 April 2017.
Jump up ^ "Trevi coins row re-surfaces". BBC News. 8 October 2003. Retrieved 18 January 2010.
Jump up ^ "Trevi fountain 'copycat' thieves arrested". BBC News. 9 August 2002. Retrieved 18 January 2010.
Bibliography
Pinto, John A. (1986). The Trevi Fountain. New Haven: Yale University Press.
External links[edit]
Wikimedia Commons has media related to Trevi Fountain.
Wikinews has related news: Man throws red paint in Roman Trevi fountain to protest film festival
Wikisource has the text of the 1905 New International Encyclopedia article Fountain of Trevi.
"Aerial view of Trevi Fountain.". Google Maps. Retrieved 6 August 2007. The fountain is the blue rounded rectangle in the centre of the photo, just west of the Quirinal Palace.
Roman Bookshelf – Trevi Fountain – Views from the 18th and 19th centuries
Trevi Fountain Virtual 360° panorama and photo gallery.
Engraving of the fountain's more modest predecessor.
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Therac-25
From Wikipedia, the free encyclopedia
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The Therac-25 was a radiation therapy machine produced by Atomic Energy of Canada Limited (AECL) in 1982 after the Therac-6 and Therac-20 units (the earlier units had been produced in partnership with CGR of France).
It was involved in at least six accidents between 1985 and 1987, in which patients were given massive overdoses of radiation.[1]:425 Because of concurrent programming errors, it sometimes gave its patients radiation doses that were hundreds of times greater than normal, resulting in death or serious injury.[2] These accidents highlighted the dangers of software control of safety-critical systems, and they have become a standard case study in health informatics and software engineering. Additionally the overconfidence of the engineers[1]:428 and lack of proper due diligence to resolve reported software bugs, is highlighted as an extreme case where the engineer's overconfidence in their initial work and failure to believe the end users' claims caused drastic repercussions.
Contents
[hide]
1 Design
2 Problem description
3 Root causes
4 See also
5 Notes
6 Additional reading
Design[edit]
The machine offered two modes of radiation therapy:[3]
Direct electron-beam therapy, in which a narrow low-current beam of high-energy (5 MeV to 25 MeV) electrons was scanned over the treatment area by magnets; and
Megavolt X-ray therapy, which delivered a fixed wide beam of X-rays, produced by colliding a narrow 100-times higher current beam of 25 MeV electrons with a target, then passing the emitted X-rays through both a flattening filter and a collimator.
A third "field-light" mode allowed the patient to be correctly positioned by illuminating the treatment area with visible light.
Problem description[edit]
The six documented accidents occurred when the high-current electron beam generated in X-ray mode was delivered directly to patients. Two software faults were to blame:[3] One, when the operator incorrectly selected X-ray mode before quickly changing to electron mode, allowed the electron beam to be set for X-ray mode without the X-ray target being in place. A second fault allowed the electron beam to activate during field-light mode, during which no beam scanner was active or target was in place.
Previous models had hardware interlocks to prevent such faults, but the Therac-25 had removed them, depending instead on software checks for safety.
The high-current electron beam struck the patients with approximately 100 times the intended dose of radiation, and over a narrower area, delivering a potentially lethal dose of beta radiation. The feeling was described by patient Ray Cox as "an intense electric shock", causing him to scream and run out of the treatment room.[4] Several days later, radiation burns appeared, and the patients showed the symptoms of radiation poisoning; in three cases, the injured patients later died as a result of the overdose.[5]
Root causes[edit]
A commission concluded that the primary reason should be attributed to the bad software design and development practices, and not explicitly to several coding errors that were found. In particular, the software was designed so that it was realistically impossible to test it in a clean automated way.[6]
Researchers who investigated the accidents found several contributing causes. These included the following institutional causes:
AECL did not have the software code independently reviewed.
AECL did not consider the design of the software during its assessment of how the machine might produce the desired results and what failure modes existed. These form parts of the general techniques known as reliability modeling and risk management.
The system noticed that something was wrong and halted the X-ray beam, but merely displayed the word "MALFUNCTION" followed by a number from 1 to 64. The user manual did not explain or even address the error codes, so the operator pressed the P key to override the warning and proceed anyway.
AECL personnel, as well as machine operators, initially did not believe complaints. This was likely due to overconfidence.[1]:428
AECL had never tested the Therac-25 with the combination of software and hardware until it was assembled at the hospital.
The researchers also found several engineering issues:
The failure only occurred when a particular nonstandard sequence of keystrokes was entered on the VT-100 terminal which controlled the PDP-11 computer: an "X" to (erroneously) select 25 MeV photon mode followed by "cursor up", "E" to (correctly) select 25 MeV Electron mode, then "Enter", all within eight seconds.[6] This sequence of keystrokes was improbable, and so the problem did not occur often and went unnoticed for a long time.[4]
The design did not have any hardware interlocks to prevent the electron-beam from operating in its high-energy mode without the target in place.
The engineer had reused software from older models. Such methods manifest in so called Cargo coding where there is blind reliance on previously created code that is poorly understood and may or may not be applicable. These models had hardware interlocks that masked their software defects. Those hardware safeties had no way of reporting that they had been triggered, so there was no indication of the existence of faulty software commands.
The hardware provided no way for the software to verify that sensors were working correctly (see open-loop controller). The table-position system was the first implicated in Therac-25's failures; the manufacturer revised it with redundant switches to cross-check their operation.
The equipment control task did not properly synchronize with the operator interface task, so that race conditions occurred if the operator changed the setup too quickly. This was missed during testing, since it took some practice before operators were able to work quickly enough to trigger this failure mode.
The software set a flag variable by incrementing it, rather than by setting it to a fixed non-zero value. Occasionally an arithmetic overflow occurred, causing the flag to return to zero and the software to bypass safety checks.
The software was written in assembly language that might require more attention for testing and good design. However the choice of language by itself is not listed as a primary cause in the report. The machine also used its own operating system.
Leveson notes that a lesson to be drawn from the incident is to not assume that reused software is safe: "A naive assumption is often made that reusing software or using commercial off-the-shelf software will increase safety because the software will have been exercised extensively. Reusing software modules does not guarantee safety in the new system to which they are transferred..."[6] This blind faith in poorly understood software coded paradigms is known as Cargo cult programming. In response to incidents like those associated with Therac-25, the IEC 62304 standard was created, which introduces development life cycle standards for medical device software and specific guidance on using software of unknown pedigree.[7]
See also[edit]
IEC 62304
Ionizing radiation
List of civilian radiation accidents
Nuclear and radiation accidents
Radiation protection
Notes[edit]
^ Jump up to: a b c Baase, Sara (2008). A Gift of Fire. Pearson Prentice Hall.
Jump up ^ Leveson, Nancy G.; Turner, Clark S. (July 1993). "An Investigation of the Therac-25 Accidents" (PDF). IEEE Computer. 26 (7): 18–41.
^ Jump up to: a b Levenson, Nancy (1995). "Safeware: System Safety and Computers. Appendix A: Medical Devices: The Therac-25" (PDF). Addison-Wesley.
^ Jump up to: a b Casey, Steven. Set Phasers On Stun - Design and Human Error. Aegean Publishing Company. pp. 11–16.
Jump up ^ Rose, Barbara Wade. "Fatal Dose - Radiation Deaths linked to AECL Computer Errors". www.ccnr.org. Retrieved 14 June 2016.
^ Jump up to: a b c Leveson, Nancy, University of Washington (1995). "Medical Devices: The Therac-25 Accidents" (PDF). Safeware: System Safety, and Computers (Update of the 1993 IEEE Computer article ed.). Addison-Wesley. CS1 maint: Multiple names: authors list (link)
Jump up ^ Hall, Ken (June 1, 2010). "Developing Medical Device Software to IEC 62304". MDDI - Medical Device and Diagnostic Industry. Retrieved 2016-12-12.
Additional reading[edit]
Gallagher, Troy. THERAC-25 Computerized Radiation Therapy. (short summary of the Therac-25 Accidents)
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