Posted by Andrew Bolt may have the worst case of confirmation bias ever seen. To Bolt, whether something is true or not has nothing to do with its accuracy and everything to do with whether it suits him or not. Here in its entirety,
If the evidence were so strong, there’d be no need for such untruths
Dennis Ambler checks the statistics behind recently claims that 97 per cent of climate scientists believe man is heating the planet and finds evidence of some exaggeration:
However a headline of “0.73% of climate scientists think that humans are affecting the climate” doesn’t quite have the same ring as 97% does it?
Er, no.
He’s referring to Doran and Zimmerman’s survey of 3146 Earth Scientists. The graph below shows their results for this question:
Do you think human activity is a significant contributing factor in changing mean global temperatures?
So what’s Ambler’s argument that proves that the 97% is really 0.73%?
The response to this question was 75 specialists out of 77, so here we have our massive 97%.
It is disingenuous to now use the “climate scientists” as a new population sample size. The response figure of 3,146 is the figure against which the 75 out of 77 should be compared and in this case we get not 97% but just 2.38%.
Err, no. Percentages don’t work that way. If you want to know the percentage of the 3146 Earth scientists that said “yes”, you have to divide the number of them that said yes (about 2580) by the sample size (3146) to get 82%.
This is something that students are supposed to learn in primary school. I would imagine that even Andrew Bolt could do primary school maths, so the reason that he didn’t notice that
Ambler was wrong was because of his confirmation bias.
Ambler gets the number down further with this:
The original number contacted was 10,157 and of those, 69% decided they didn’t want any part of it, but they were the original target population. When the figure of 75 believers is set against that number, we get a mere 0.73% of the scientists they contacted who agreed with their loaded questions.
We don’t know how the non-responders would have answered, but it is clearly wrong to assume, as Ambler does and Bolt blindly agrees, that they would all have answered “no”. The most reasonable assumption is that they their answers would be similar to that of the responders and 82% of Earth scientists would say “yes”. And this does not contradict the 97% figure, which was for active climate scientists.
The sad thing is that I don’t think Bolt is lying — why write something so easily shown to be untrue? Bolt’s severe confirmation bias mean that he is a less reliable source of information than someone who lies strategically.
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