Editing Confirmation bias (section)

=== Cognitive versus motivational ===
[[File:Felicidade A very happy boy.jpg|thumb|250x250px|Happy events are more likely to be remembered.]]
According to [[Robert MacCoun]], most biased evidence processing occurs through a combination of "cold" (cognitive) and "hot" (motivated) mechanisms.<ref>{{Harvnb|MacCoun|1998}}</ref>

Cognitive explanations for confirmation bias are based on limitations in people's ability to handle complex tasks, and the shortcuts, called ''[[heuristics in judgment and decision making|heuristics]]'', that they use.<ref>{{Harvnb|Friedrich|1993|p=298}}</ref> For example, people may judge the reliability of evidence by using the ''[[availability heuristic]]'' that is, how readily a particular idea comes to mind.<ref>{{Harvnb|Kunda|1999|p=94}}</ref> It is also possible that people can only focus on one thought at a time, so find it difficult to test alternative hypotheses in parallel.<ref name ="nickerson"/>{{rp|198–199}} Another heuristic is the positive test strategy identified by Klayman and Ha, in which people test a hypothesis by examining cases where they expect a property or event to occur. This heuristic avoids the difficult or impossible task of working out how diagnostic each possible question will be. However, it is not universally reliable, so people can overlook challenges to their existing beliefs.<ref name="klaymanha" /><ref name ="nickerson"/>{{rp|200}}

Motivational explanations involve an effect of [[desire (emotion)|desire]] on [[belief]].<ref name ="nickerson"/>{{rp|197}}<ref>{{Harvnb|Baron|2000|p=206}}</ref> It is known that people prefer positive thoughts over negative ones in a number of ways: this is called the "[[Pollyanna principle]]".<ref>{{Citation |last=Matlin |first=Margaret W. |title=Cognitive illusions: A handbook on fallacies and biases in thinking, judgement and memory |editor-first=Rüdiger F. |editor-last=Pohl |publisher=[[Psychology Press]] |location=Hove, UK |year=2004 |pages=[https://archive.org/details/cognitiveillusio0000unse/page/255 255–272] |chapter=Pollyanna Principle |isbn=978-1-84169-351-4 |oclc=55124398 |chapter-url=https://archive.org/details/cognitiveillusio0000unse/page/255}}</ref> Applied to [[argument]]s or sources of [[evidence]], this could explain why desired conclusions are more likely to be believed true. According to experiments that manipulate the desirability of the conclusion, people demand a high standard of evidence for unpalatable ideas and a low standard for preferred ideas. In other words, they ask, "Can I believe this?" for some suggestions and, "Must I believe this?" for others.<ref>{{Citation|last1=Dawson |first1=Erica |first2=Thomas |last2=Gilovich |author-link2=Thomas Gilovich |first3=Dennis T. |last3=Regan |date=October 2002 |title=Motivated reasoning and performance on the Wason Selection Task |journal=Personality and Social Psychology Bulletin |volume=28 |issue=10 |pages=1379–1387 |doi=10.1177/014616702236869|s2cid=143957893 }}</ref><ref>{{Citation |last1=Ditto |first1=Peter H. |first2= David F. |last2=Lopez |year=1992 |title=Motivated skepticism: Use of differential decision criteria for preferred and nonpreferred conclusions |journal=[[Journal of Personality and Social Psychology]] |volume=63 |issue=4 |pages=568–584 |issn=0022-3514 |doi=10.1037/0022-3514.63.4.568}}</ref> Although [[consistency]] is a desirable feature of attitudes, an excessive drive for consistency is another potential source of bias because it may prevent people from neutrally evaluating new, surprising information. Social psychologist [[Ziva Kunda]] combines the cognitive and motivational theories, arguing that motivation creates the bias, but cognitive factors determine the size of the effect.<ref name ="nickerson"/>{{rp|198}}