Editing Confirmation bias (section)

=== Science and scientific research ===
{{See also|Planck's principle|Escalation of commitment|Replication crisis}}

A distinguishing feature of [[science|scientific thinking]] is the search for confirming or supportive evidence ([[inductive reasoning]]) as well as falsifying evidence ([[deductive reasoning]]).<ref>{{Citation|journal=Cognitive Therapy and Research|volume=1|issue=3|pages=229–238|title=Psychology of the scientist: An analysis of problem-solving bias|first1=Michael J.|last1=Mahoney |first2=B.G.|last2=DeMonbreun |year=1977|doi=10.1007/BF01186796|s2cid=9703186}}</ref><ref>{{Citation|title=Norms and counter-norms in a select group of the Apollo moon scientists: A case study of the ambivalence of scientists|first=I. I.|last=Mitroff|journal=American Sociological Review|year=1974|volume=39|issue=4|pages=579–395|jstor=2094423|doi=10.2307/2094423}}
</ref>

Many times in the [[history of science]], scientists have resisted new discoveries by selectively interpreting or ignoring unfavorable data.<ref name ="nickerson"/>{{rp|192–194}} Several studies have shown that scientists rate studies that report findings consistent with their prior beliefs more favorably than studies reporting findings inconsistent with their previous beliefs.<ref name="Hergovich 2010" /><ref name="Koehler 1993">{{Harvnb|Koehler|1993}}</ref><ref name="Mahoney 1977">{{Harvnb|Mahoney|1977}}</ref>

However, assuming that the research question is relevant, the experimental design adequate and the data are clearly and comprehensively described, the empirical data obtained should be important to the scientific community and should not be viewed prejudicially, regardless of whether they conform to current theoretical predictions.<ref name="Mahoney 1977"/> In practice, researchers may misunderstand, misinterpret, or not read at all studies that contradict their preconceptions, or wrongly cite them anyway as if they actually supported their claims.<ref name="Letrud & Hernes 2019">{{cite journal|last1=Letrud|first1=Kåre|last2=Hernes|first2=Sigbjørn|title=Affirmative citation bias in scientific myth debunking: A three-in-one case study|journal=PLOS ONE|volume=14|issue=9|year=2019|pages=e0222213|doi=10.1371/journal.pone.0222213|pmid=31498834|pmc=6733478|bibcode=2019PLoSO..1422213L|doi-access=free|mode=cs2}}</ref>

Further, confirmation biases can sustain scientific theories or research programs in the face of inadequate or even contradictory evidence.<ref name="sutherland">{{Citation |last=Sutherland |first=Stuart |title=Irrationality |edition=2nd |publisher= Pinter and Martin |location=London |year=2007 |pages=95–103 |isbn=978-1-905177-07-3 |oclc=72151566}}</ref><ref>{{cite web | url =http://nautil.us/issue/24/error/the-trouble-with-scientists | title =The trouble with scientists: How one psychologist is tackling human biases in science | last =Ball | first =Phillip | date =14 May 2015 | website =Nautilus | access-date =6 October 2019 | mode =cs2 | archive-date =7 October 2019 | archive-url =https://web.archive.org/web/20191007124310/http://nautil.us/issue/24/error/the-trouble-with-scientists | url-status =dead }}</ref> The discipline of [[parapsychology]] is often cited as an example.<ref>{{Citation |last=Sternberg |first=Robert J. |author-link=Robert Sternberg |editor1-first=Robert J. |editor1-last=Sternberg |editor2-first=Henry L. |editor2-last=Roediger III |editor3-first=Diane F. |editor3-last=Halpern |title=Critical thinking in psychology |year=2007 |publisher=Cambridge University Press |isbn=978-0-521-60834-3 |oclc=69423179 |page=292 |chapter=Critical thinking in psychology: It really is critical |quote=Some of the worst examples of confirmation bias are in research on parapsychology ... Arguably, there is a whole field here with no powerful confirming data at all. But people want to believe, and so they find ways to believe.}}</ref>

An experimenter's confirmation bias can potentially affect which data are reported. Data that conflict with the experimenter's expectations may be more readily discarded as unreliable, producing the so-called [[publication bias|file drawer effect]]. To combat this tendency, scientific training teaches ways to prevent bias.<ref name="shadish">{{Citation |last=Shadish |first=William R. |title= Critical Thinking in Psychology |editor1-first=Robert J. |editor1-last=Sternberg |editor2-first=Henry L. |editor2-last=Roediger III |editor3-first=Diane F. |editor3-last=Halpern |publisher=Cambridge University Press |year=2007 |page=49 |chapter=Critical thinking in quasi-experimentation |isbn=978-0-521-60834-3}}</ref> For example, [[Design of experiments|experimental design]] of [[randomized controlled trial]]s (coupled with their [[systematic review]]) aims to minimize sources of bias.<ref name="shadish" /><ref>{{Citation | doi = 10.1136/bmj.323.7303.42 | last1 = Jüni | first1 = P.| last2 = Altman | first2 = D.G.| last3 = Egger | first3 = M.| title = Systematic reviews in health care: Assessing the quality of controlled clinical trials | journal = BMJ (Clinical Research Ed.)| volume = 323| issue = 7303| pages = 42–46| year = 2001| pmid = 11440947 | pmc = 1120670}}</ref>

The social process of [[peer review]] aims to mitigate the effect of individual scientists' biases, even though the peer review process itself may be susceptible to such biases<ref>{{Citation|last1=Lee|first1=C.J.|last2=Sugimoto|first2=C.R.|author2-link=Cassidy Sugimoto|last3=Zhang|first3=G.|last4=Cronin|first4=B.|year=2013|title=Bias in peer review|journal=Journal of the Association for Information Science and Technology|volume=64|pages=2–17|doi=10.1002/asi.22784}}</ref><ref>{{Citation |last=Shermer |first=Michael |author-link=Michael Shermer|date=July 2006 |title=The political brain: A recent brain-imaging study shows that our political predilections are a product of unconscious confirmation bias |journal=[[Scientific American]] |volume=295 |issue=1 |pages=36 |issn=0036-8733 |bibcode=2006SciAm.295a..36S |doi=10.1038/scientificamerican0706-36 |pmid=16830675 }}</ref><ref name="Mahoney 1977" /><ref>{{Citation | last1 = Emerson | first1 = G.B.| last2 = Warme | first2 = W.J.| last3 = Wolf | first3 = F.M.| last4 = Heckman | first4 = J.D.| last5 = Brand | first5 = R.A.| last6 = Leopold | first6 = S.S.| doi = 10.1001/archinternmed.2010.406 | title = Testing for the presence of positive-outcome bias in peer review: A randomized controlled trial | journal = [[Archives of Internal Medicine]] | volume = 170 | issue = 21| pages = 1934–1339 | year = 2010 | pmid = 21098355 | doi-access =  }}</ref><ref name="Bartlett 2011">Bartlett, Steven James, "The psychology of abuse in publishing: Peer review and editorial bias," Chap. 7, pp. 147–177, in [[Steven James Bartlett]], ''Normality does not equal mental health: The need to look elsewhere for standards of good psychological health''. Santa Barbara, CA: Praeger, 2011.</ref> Confirmation bias may thus be especially harmful to objective evaluations regarding nonconforming results since biased individuals may regard opposing evidence to be weak in principle and give little serious thought to revising their beliefs.<ref name="Koehler 1993" /> Scientific innovators often meet with resistance from the scientific community, and research presenting controversial results frequently receives harsh peer review.<ref>{{Citation |doi=10.1001/jama.263.10.1438 |last=Horrobin |first=David F. |author-link=David Horrobin |year=1990 |title=The philosophical basis of peer review and the suppression of innovation |journal=[[Journal of the American Medical Association]] |pmid=2304222 |volume=263 |issue=10 |pages=1438–1441 }}</ref>