"Monetary preference falsification": a thought experiment to test the validity of adding monetary incentives to politically motivated reasoning experiments
Friday, March 11, 2016 at 2:19AM
Dan Kahan

From something or other and basically an amplification of point from Kahan (in press) 

1.  Monetary preference falsification

Imagine I am solicited and agree to participate in an experiment by researchers associated with the “Moon Walk Hoax Society,” which is dedicated to “exposing the massive fraud perpetrated by the U.S. government, in complicity with the United Nations, in disseminating the misimpression that human beings visited the Moon in 1969 or at any point thereafter.”  These researchers present me with a "study" containing what I’m sure are bogus empirical data suggesting that a rocket the size of Apollo 11 could not have contained a sufficient amount of fuel to propel a spacecraft to the surface of the moon.

After I read the study, I am instructed that I will be asked questions about the inferences supported by the evidence I just examined and will be offered a monetary reward (one that I would actually find meaningful; I am not an M Turk worker, so it would have to be more than $0.10, but as a poor university professor, $1.50 might suffice) for “correct answers.”  The questions all amount to whether the evidence presented supports the conclusion that the 1969 Moon-landing never happened.

Because I strongly suspect that the researchers believe that that is the “correct” answer, and because they’ve offered to pay me if I claim to agree, I indicate that the evidence—particularly the calculations that show a rocket loaded with as much fuel as would fit on the Apollo 11 could never have made it to the Moon—isvery persuasive proof that the 1969 Moon landing for sure didn't really  occur.

If a large majority of the other experiment subjects respond the way I do, can we infer from the experiment that all the "unincentivized" responses that pollsters have collected on the belief that humans visited the Moon in 1969 are survey “artifacts,” & that the appearance of widespread public acceptance of this “fact” is “illusory” (Bullock, Gerber, Hill & Huber 2015)? 

As any card-carrying member of the “Chicago School of Behavioral Economics, Incentive-Compatible Design Division” will tell you the answer is, "Hell no, you can't!" 

Under these circumstances, we should anticipate that a great many subjects who didn’t find the presented evidence convincing will have said they did in order to earn money by supplying the response they anticipated the experimenters would pay them for.

Imagine further that the researchers offered the subjects the opportunity, after they completed the portion of the experiment for which they were offered incentives for “correct” answers, to indicate whether they found the evidence “credible.”  Told that at this point there would be no “reward” for a “correct” answer or penalty for an incorrect one, the vast majority of the very subjects who said they thought the evidence proved that the moon landing was faked now reveal that they thought the study was a sham (Khanna & Sood 2016).

Obviously, it would be much more plausible to treat that "nonincentivized" answer as the one that finally revealed what all the respondents truly believed.

By their own logic, researchers who argue that monetary incentives can be used to test the validity of experiments on politically motivated reasoning invite exactly this response to their studies.  These researchers might not have expectations as transparent or silly as those of the investigators who designed the "Moon walk hoax" public opinion study.  But they are furnishing their subjects with exactly the same incentive: to make their best guess about what the experimenter will deem to be a "correct" response--not to reveal their own "true beliefs" about politically contested facts.

Studies as interesting as Khanna and Sood (2016) can substantially enrich scholarly inquiry. But seeing how requires looking past the patently unpersuasive claim that "incentive compatible methods" are suited for testing the external validity of politically motivated reasoning experiments (Bullock, Gerber, Hill & Huber 2015).


Bullock, J.G., Gerber, A.S., Hill, S.J. & Huber, G.A. Partisan Bias in Factual Beliefs about Politics. Quarterly Journal of Political Science 10, 519-578 (2015).

Kahan, D.M. The Politically Motivated Reasoning ParadigmEmerging Trends in Social & Behavioral Sciences, (in press). 

Khanna, Kabir &  Sood, Gaurav. Motivated Learning or Motivated Responding? Using Incentives to Distinguish Between Two Processes (2016), available at http://www.gsood.com/research/papers/partisanlearning.pdf.

Article originally appeared on cultural cognition project (http://www.culturalcognition.net/).
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