Editing Interaction (statistics) (section)

==Examples==
Real-world examples of interaction include:
*''Interaction'' between adding sugar to coffee and stirring the coffee. Neither of the two individual variables has much effect on sweetness but a combination of the two does.
*''Interaction'' between adding [[carbon]] to [[steel]] and [[quenching]]. Neither of the two individually has much effect on [[tensile strength|strength]] but a combination of the two has a dramatic effect.
*''Interaction'' between smoking and inhaling [[asbestos]] fibres: Both raise lung carcinoma risk, but exposure to asbestos ''multiplies'' the cancer risk in smokers and non-smokers. Here, the ''joint effect'' of inhaling asbestos and smoking is higher than the sum of both effects.<ref>{{Cite journal
 | author = Lee, P. N.
 | year = 2001
 | title = Relation between exposure to asbestos and smoking jointly and the risk of lung cancer
 | journal = Occupational and Environmental Medicine
 | volume = 58
 | issue = 3
 | pages = 145–53
 | doi = 10.1136/oem.58.3.145
 | pmid = 11171926
 | pmc = 1740104
 }}</ref>
*''Interaction'' between genetic risk factors for [[Diabetes mellitus type 2|type 2 diabetes]] and diet (specifically, a "western" dietary pattern). The western dietary pattern was shown to increase diabetes risk for subjects with a high "genetic risk score", but not for other subjects.<ref>{{Cite journal | author = Lu, Q. | year = 2009 | title = Genetic predisposition, Western dietary pattern, and the risk of type 2 diabetes in men | journal = Am J Clin Nutr | volume = 89 | pages = 1453&ndash;1458 | doi = 10.3945/ajcn.2008.27249 | pmid = 19279076 | display-authors = 1 | issue = 5 | author2 = <Please add first missing authors to populate metadata.>| pmc = 2676999 }}</ref>
*''Interaction'' between education and political orientation, affecting general-public perceptions about climate change. For example, US surveys often find that acceptance of the reality of [[anthropogenic climate change]] rises with education among moderate or liberal survey respondents, but declines with education among the most conservative.<ref>{{cite journal | last1 = Hamilton | first1 = L.C. | year = 2011 | title = Education, politics and opinions about climate change: Evidence for interaction effects | url = https://scholars.unh.edu/cgi/viewcontent.cgi?article=1388&context=soc_facpub| journal = [[Climatic Change (journal)|Climatic Change]] | volume = 104 | issue = 2| pages = 231–242 | doi = 10.1007/s10584-010-9957-8 | bibcode = 2011ClCh..104..231H | s2cid = 16481640 | url-access = subscription }}</ref><ref>{{cite journal |last=McCright |first=A. M. |year=2011 |title=Political orientation moderates Americans' beliefs and concern about climate change |journal=[[Climatic Change (journal)|Climatic Change]] |doi=10.1007/s10584-010-9946-y |volume=104 |issue=2 |pages=243–253 |bibcode=2011ClCh..104..243M |s2cid=152795205 }}</ref> Similar interactions have been observed to affect some non-climate science or environmental perceptions,<ref>{{Cite journal | doi=10.1080/09644016.2014.976485|title = A four-party view of US environmental concern| journal=Environmental Politics| volume=24| issue=2| pages=212–227|year = 2015|last1 = Hamilton|first1 = Lawrence C.| last2=Saito| first2=Kei| bibcode=2015EnvPo..24..212H |s2cid = 154762226}}</ref> and to operate with science literacy or other knowledge indicators in place of education.<ref>{{cite journal | last1 = Kahan | first1 = D.M. | last2 = Jenkins-Smith | first2 = H. | last3 = Braman | first3 = D. | year = 2011 | title = Cultural cognition of scientific consensus | url = https://scholarship.law.gwu.edu/cgi/viewcontent.cgi?article=1269&context=faculty_publications| journal = Journal of Risk Research | volume = 14 | issue = 2| pages = 147–174 | doi = 10.1080/13669877.2010.511246 | hdl = 10.1080/13669877.2010.511246 | s2cid = 216092368 | hdl-access = free }}</ref><ref>{{cite journal | last1 = Hamilton | first1 = L.C. | last2 = Cutler | first2 = M.J. | last3 = Schaefer | first3 = A. | year = 2012 | title = Public knowledge and concern about polar-region warming | journal = [[Polar Geography]] | volume = 35 | issue = 2| pages = 155–168 | doi = 10.1080/1088937X.2012.684155 | bibcode = 2012PolGe..35..155H | s2cid = 12437794 }}</ref>