streetlight effect

{{Short description|Observational bias from only searching where it is easiest to look}}

{{distinguish|Street light interference phenomenon}}

{{use mdy dates|date=September 2022}}

File:公园中的艺术路灯.jpg

The streetlight effect, or the drunkard's search principle, is a type of observational bias that occurs when people only search for something where it is easiest to look.{{cite news |author=David H. Freedman |title=The Streetlight Effect |work=Discover |date=August 1, 2010 |accessdate=2010-08-24 |url=http://discovermagazine.com/2010/jul-aug/29-why-scientific-studies-often-wrong-streetlight-effect }}
- Sufism/Nasrudin on Wikibooks
- {{Cite journal|title = The Streetlight Effect in Type 1|journal = Diabetes|date = 2015-04-01|issn = 0012-1797|pmc = 4375074|pmid = 25805758|pages = 1081–1090|volume = 64|issue = 4|doi = 10.2337/db14-1208|first1 = Manuela|last1 = Battaglia|first2 = Mark A.|last2 = Atkinson}} Both names refer to a well-known joke:

{{quote|A policeman sees a drunk man searching for something under a streetlight and asks what the drunk has lost. He says he lost his keys and they both look under the streetlight together. After a few minutes the policeman asks if he is sure he lost them here, and the drunk replies, no, and that he lost them in the park. The policeman asks why he is searching here, and the drunk replies, "this is where the light is".{{cite book |author=David H. Freedman |title=Wrong: Why Experts Keep Failing Us|year=2010 |publisher=Little, Brown and Company | url=https://books.google.com/books?id=XS4TQgAACAAJ |isbn=978-0-316-02378-8|via=Google Books }}
- Sufism/Nasrudin on Wikibooks

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| image1 = Observational bias 1 - a set of random dots.png

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| image2 = Observational bias 3 - Most random dots go undetected.png

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| image3= Observational bias 4 - Illusion that dots cluster near observation posts.png

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| footer = In a visual demonstration of surveillance bias, points are placed completely at random (white dots, top). Points are most likely to be detected (red dots, middle) if they are near a region of heighted scrutiny (yellow). The detected results (red dots, bottom) appear clustered around hotspots.

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The anecdote is attributed to Nasreddin. According to Idries Shah, this tale is used by many Sufis, commenting upon people who seek exotic sources for enlightenment.{{Cite book|url=https://archive.org/details/sufis00shah_0|url-access=registration|title=The Sufis |last=Shah|first=Idries|date=1964 |publisher=Doubleday |isbn=9780385079662|pages=[https://archive.org/details/sufis00shah_0/page/62 62]}} Outside of the Nasreddin corpus, the anecdote goes back at least to the 1920s,"'Did You Lose the Keys Here?' 'No, But the Light Is Much Better Here'", Quote Investigator [https://quoteinvestigator.com/2013/04/11/better-light/ April 4, 2013]
- {{cite journal|title=Bulletin of the Atomic Scientists|journal=Bulletin of the Atomic Scientists: Science and Public Affairs|date=December 1960|publisher=Educational Foundation for Nuclear Science, Inc.|issn=0096-3402|url=https://archive.org/details/bub_gb_HAoAAAAAMBAJ|page=[https://archive.org/details/bub_gb_HAoAAAAAMBAJ/page/n20 9]|accessdate=2017-01-08}}
- {{cite book|title=Hearings on Science Legislation (S. 1297 and Related Bills): Hearings Before a Subcommittee of the Committee on Military Affairs, United States Senate, Seventy-ninth Congress, First Session, Pursuant to S. Res. 107 (78th Congress) and S. Res. 146 (79th Congress) Authorizing a Study of the Possibilities of Better Mobilizing the National Resources of the United States|author=United States Senate Committee on Military Affairs|date=1945|issue=pts. 1-6|publisher=U.S. Government Printing Office|url=https://books.google.com/books?id=M9baAAAAMAAJ|accessdate=2017-01-08|via=Google Books}}
- {{cite book|title=Report of the Organization and of the... Annual Meeting of the Alabama State Bar Association|author=Alabama State Bar Association|date=July 1926|page=94|publisher=Smith & Armstrong|url=https://books.google.com/books?id=BmMdAQAAMAAJ&q=%22daddy%27s+watch%22|accessdate=2017-01-08|via=Google Books}}

and has been used metaphorically in the social sciences since at least 1964, when Abraham Kaplan referred to it as "the principle of the drunkard's search".{{cite book|author = Kaplan, Abraham|author-link = Abraham Kaplan|year = 1964|title = The Conduct of Inquiry: Methodology for Behavioral Science|url = https://books.google.com/books?id=OYe6fsXSP3IC|page = 11|publisher = Transaction Publishers|isbn = 9781412836296|accessdate = 2014-10-08|via=Google Books}} Noam Chomsky, for instance, uses the tale as a picture of how science operates: "Science is a bit like the joke about the drunk who is looking under a lamppost for a key that he has lost on the other side of the street, because that's where the light is. It has no other choice."{{cite book |last=Barsky |first=Robert F. |title=Noam Chomsky: a life of dissent |date=1998 |publisher=MIT Press |location=Cambridge, Mass. |isbn=0262024187 |page=95 |edition=Repr. |url = https://books.google.com/books?id=RKUbyYPG4mcC&dq=%E2%80%9CScience+is+a+bit+like+the+joke+about+the+drunk+who+is+looking+under+a+lamppost+for+a+key+that+he+has+lost+on+the+other+side+of+the+street%2C+because+th&pg=PA95|access-date=23 July 2022|via=Google Books}}

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