In the Republican Brain, Chris Mooney describes how conservative Republicans have lost their mooring to reality, from cupidity or stupidity or just desire for life on another planet. Whether you believe this or not, depends to some extent on you position about reality. As Dan Kahan put it
As it turns out, I don’t feel persuaded of the central thesis of The Republican Brain. That is, I’m not convinced that the mass of studies that it draws on supports the inference that Republicans/conservatives reason in a manner that is different from and less reasoned than Democrats/liberals.
And Kahan and colleagues (Peters, Slovic and Cantrell Dawson) set out to do
an experiment that shows that Mooney got it right, of course, without setting out to do an experiment that showed that Mooney got it right, but that is what they did.
Now Kahan is of the school that you might as well save your breath, that no amount of knowledge will budge cultural orientation, what he calls the “Identity-protective Cognition Thesis” (ICT). This is opposed by a more loosely defined Deficit Model, that providing some factual material helps. In the paper, ICT is contrasted to the SCT
“Science Comprehension Thesis” (SCT), which identifies defects in the public’s knowledge and reasoning capacities as the source of such controversies; and the “Identity-protective Cognition Thesis” (ICT), which treats cultural conflict as disabling the faculties that members of the public use to make sense of decision-relevant science.
If you read Huffington Post, the claims are all or nothing, but if you back bunnies into a corner you get an it depends on how committed people are to their ideology, and certainly education, information, etc. has an effect, which is why the pushback on anything that shows how strongly those who study climate believe that people are having a major negative effect on climate
Briefly put Kahan, et al's subjects were classified as Conservative Republican or Liberal Democrat, and within each group those who could divide (the numerate) were separated from those who could not (the innumerate). Selected members from each group were given ~ninth grade ratio problems of moderate difficulty
One was about a new skin rash treatment
|
Rash Got Better
|
Rash Got Worse
|
Patients who did use the new skin cream
|
223
|
75
|
Patients who did not use the new skin cream
|
107
|
21
|
and the other was about
|
Increase in Crime
|
Decrease in Crime
|
Cities that did ban carrying concealed handguns in
public
|
223
|
75
|
Cities that did not ban carrying concealed handguns in
public
|
107
|
21
|
They also flipped the outcomes, for example
|
Decrease in Crime
|
Increase in Crime
|
Cities that did ban carrying concealed handguns in
public
|
223
|
75
|
Cities that did not ban carrying concealed handguns in
public
|
107
|
21
|
and the questions were, was the skin cream effective or not, or were concealed carry laws effective or not. (UPDATE: Since readers are picking exactitude the actual questions were People who used the skin cream were more likely to
get better/get worse than those who didn't. Eli also changed the titles on the columns to the ones used which he had shortened to save space)
For the purposes of this post, let's look at their predicted probability of getting the right answers and discuss the various takes.
Kahan, et al's take on this is
also strongly disconfirms the second, SCT hypothesis. A low-Numeracy Liberal Democrat is more likely to correctly identify the outcome supported by the data than is a low-Numeracy Conservative Republican when the data, in fact, supports the conclusion that a gun ban decreases crime, but is less likely to correctly identify the outcome when the data supports the conclusion that a gun ban increases crime. This pattern of polarization, contrary to the SCT hypothesis, does not abate among high Numeracy subjects.
Michael Tobis, at Planet 3.0
has a different take, calling this Kahan's latest mistake, an example of the Juggler's Paradox because "Kahan is not measuring what he claims he is measuring. Not at all."
Consider the comparable experiment with people who can juggle on one side and people who can’t juggle on the other. Set up a pair of juggling tests, one under ordinary conditions and the other in the presence of sudden, random, loud noises. The preformance of the adept will decline. The performance of those who cannot do the task under the best of circumstances will stay the same.
Can we therefore conclude that “highly dextrous people are more subject to distraction than clumsy ones”? Well, sort of, but it doesn’t really tell us very much of interest.
Can we conclude that “they applied their dexterity to the task of dropping the ball”? In this case that doesn’t even make any sense. Why should the analogous reason be relevant in Kahan’s?
In short, MT is pointing out that the numerate always do better than the innumerate, although there is certainly an ICT effect and but SCT also plays a role and one would expect this to be stronger among the less politically committed.
Eli, being a dumb bunny, would like to point out the interesting Baskerville hound in the data which Kahan et al do not hear. Specifically the results in all cases for the dumb liberals stayed about the same. In fact, if there is any significant change for the dumb liberals it is a move against ideology (they did better on the crime increases data than on the rash increases). In other words when faced with data that contradicted their ideology, they gave the problem more consideration.
The numerate and innumerate conservatives went with their prejudices. To a much lesser extent the numerate liberals did, but note that their crime decreases answers pretty well matched their rash decreases distribution, e.g. they did not let their prejudices distort their answers in that regard, although they did so to a much lesser extent than the conservatives on the opposite proposition.
What Kahan has really shown is that conservative republicans are barking mad. Sadly so.
His study certainly "supports the inference that Republicans/conservatives reason in a manner that is different from and less reasoned than Democrats/liberals."