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Wikipedia and controversial science topics

Wikipedia is world’s most popular online encyclopedia, the sixth most visited website in America, and a source most students rely on. But, according to a recent study, Wikipedia entries on politically controversial science topics can be especially unreliable.

Co-author Gene Likens is President Emeritus of the Cary Institute of Ecosystem Studies. He co-discovered acid rain in North America, and counts among his accolades a National Medal of Science. Since 2003, Likens has monitored Wikipedia’s acid rain entry.

“We found that for topics that are controversial – not scientifically controversial but politically controversial, like climate change, evolution, and acid rain – that they could be changed very quickly and are changed very often in contrast to topics that are not as controversial.  And the result of that is that if two people were to go into Wikipedia even minutes apart, they could get information that could be diametrically different.”     

Across the board, politically controversial scientific topics were more heavily edited. Wikipedia’s global warming entry sees 2-3 edits a day, with more than 100 words altered, while the standard model in physics has around 10 words changed every few weeks. The dynamic nature of politically controversial science topic entries makes it difficult for experts to monitor their accuracy.

Likens and Wilson suggest identifying Wikipedia entries that are known to have a high rate of change. They also recommend quantifying the reputation of individual editors. In the meantime, users should cast a critical eye on Wikipedia source material, which is found at the bottom of each entry.

Produced in collaboration with WAMC Northeast Public Radio, this podcast originally aired on September 24, 2015. To access a full archive of Earth Wise podcasts, visit:

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