Are the opinions of expert economists persuasive? The answer to that question will no doubt depend on who you ask. And at least some would answer 'yes, but I wish they weren't'. Does the gender of the economist matter for how persuasive their opinion is? That is a much more difficult question to answer. However, this recent article by Hans Sievertsen and Sarah Smith (both University of Bristol), published in the Journal of Economic Behavior and Organization (open access, but see this paywalled FT article as well), provides us with a starting point. Sievertsen and Smith:
...use an information provision experiment... to test whether the opinion about a topical policy issue expressed by a senior female economist is more, or less, persuasive than the same opinion expressed by a senior male economist. We run the same experiment twice – the first time, members of the public are shown credentials of expertise, the second time they are not.
Specifically, Sievertsen and Smith survey people in the US, asking their opinion on a range of issues (rated on a five-point scale from 'strongly disagree' to 'strongly agree'). Alongside a statement of the issue, each research participant was provided with the opinion of an economist, drawn from the US Economic Experts Panel run out of the University of Chicago. By comparing the results from the survey with those of an earlier survey of people who didn't get to see an economist's opinion, the persuasiveness of the economist whose opinion is provided (on each issue) can be evaluated.
The ten issues are based on the following statements:
1. Use of artificial intelligence over the next ten years will lead to a substantial increase in the growth rates of real per capita income in the US and Western Europe over the subsequent two decades.
2. There needs to be more government regulation around Twitter’s content moderation and personal data protection.
3. It would serve the US economy well to make it unlawful for companies with revenues over $1 billion to offer goods or services for sale at an excessive price during an exceptional market shock. (Price Gouging)
4. Efforts to achieve the goal of reaching net-zero emissions of greenhouse gases by 2050 will be a major drag on global economic growth.
5. Given the centrality of semiconductors to the manufacturing of many products, securing reliable supplies should be a key strategic objective of national policy.
6. A significant factor behind today’s higher US inflation is dominant corporations in uncompetitive markets taking advantage of their market power to raise prices. (Greedflation)
7. Financial regulators in the US and Europe lack the tools and authority to deter runs on banks by uninsured depositors.
8. When economic policy-makers are unable to commit credibly in advance to a specific decision rule, they will often follow a poor policy trajectory.
9. A windfall tax on the profits of large oil companies ‚ with the revenue rebated to households‚ would provide an efficient means to protect the average US household.
10. A ban on advertising junk foods (those that are high in sugar, salt, and fat) would be an effective policy to reduce child obesity.
The economists' actual views on each of the statements is not important for the research question (although the article does tell you, and you can probably guess for some of them what the average opinion of the economists is). Sievertsen and Smith first evaluate how persuasive economists are in general, finding that:
On average, a one-point change on the Likert scale in expert opinion is associated with a 0.17 point change in public opinion... Expert opinions have no effect on public opinions about Greedflation, while there are stronger effects for Price Gouging, Financial Regulation and Economic Policy. There is some support for the argument... that persuaders are more effective when receivers are less certain: The degree of persuasiveness is weaker on issues where baseline public opinion is more certain... The degree of persuasiveness is also stronger on issues where there is less distance between sub-panel expert opinion and baseline public opinion... this suggests that experts may be perceived as less credible when their views are further out of line with those of the general public.
So, the opinions of economic experts are convincing (somewhat). The last point is interesting though - people are most convinced when the economist's views are similar to those of the general public. This suggests some confirmation bias - people believe the experts more when the experts agree with them! It is also interesting who is persuaded most:
The degree of persuasiveness is greater for men [p = 0.002] and for non-whites [p = 0.000]. It is also greater for those with a degree [p = 0.000] and for those with higher self-reported economics knowledge [p = 0.000]. Those who identify as Republicans are also more persuaded by economists’ opinions than Democrats/Independents [p = 0.030].
Those who are more educated, and who claim to have more economics knowledge, are more persuaded by expert economists. More educated people likely give more credence to the views of other educated people, while those who claim to know more economics are more likely to modify their views to fit with those of economics experts.
What about gender differences in persuasion? Sievertsen and Smith switch the analysis to evaluating whether the opinion of the research participants exactly matches that of the expert whose opinion they are provided, and find that:
...members of the public are 1.1 percentage points more likely to match with the opinion of a female expert than with the same opinion expressed by a male economist.
Sievertsen and Smith find similar results when evaluating the distance between the opinion of the research participant and the expert (the distance is smaller for female experts). The effect (1.1 percentage points, against a match rate for male experts of 33.5 percent) seems quite small, but Sievertsen and Smith note that some matches would happen purely by chance, and after accounting for that:
...the degree of persuasiveness of female expert opinions is around 20 per cent higher {than male experts]...
Why are female economics experts so persuasive? Here's where things get interesting. Sievertsen and Smith run their survey a second time. The first time around, research participants were told the name and institutional affiliation of the expert economist (as well as shown their profile photo). In the second survey, research participants were only told the name of the expert economist (and shown the photo). In that second survey:
The overall effect of
female expert on the probability of matching opinion drops from 0.011 in the main experiment to 0.0002 in the follow-up.
The extra persuasiveness of female experts (over and above male experts) disappears! Sievertsen and Smith conclude that:
...in the first experiment, credentials provided an information signal that favoured senior female experts. Removing that signal in the follow-up experiment eliminates the gender difference.
It is worth explaining that last result in a bit more detail, because what it really shows is that the general public recognises the gender bias in top economics institutions.
The quality of a purported economics expert is private information. it is known to the expert themselves, but not known to the public. This is a case of asymmetric information. The expert is the informed party, and the general public is the uninformed party. Since the general public cannot tell high-quality and low-quality experts apart, they might assume that all experts are low quality. How can a high-quality expert instead convince the general public of their high quality? They must credibly reveal their quality to the public - this is called signalling.
For a signal to be effective, it must meet two conditions: (1) it must be costly; and (2) it must be costly in such a way that those with low quality attributes would not want to attempt the signal. Getting a tenured position is signal of high quality for experts. It is costly to get such a position, and it is costly in a way that low-quality experts wouldn't want to attempt it (because they would be unsuccessful in getting tenure anyway). So, a position at a top university is a signal of quality.
Now, why would this signal be even more effective for female economists? If getting a tenured position at a top institution is even more costly for female economists than for male economists, then the quality of the signal is higher for women than for men. And therefore, the general public would be even more believing of the signal for female economists than for male economists. The gender gap in economics is pervasive (see this post, and the posts linked at the bottom of that post). What is interesting is that this gender gap is so well established that the general public is acting on it!
Sievertsen and Smith finish by pointing out a bit of a paradox:
...if senior female economists have greater credibility in the eyes of the public, then why are they less confident in giving their opinion. This remains an open question.
Indeed. Hopefully, at the margin, this research will convince senior female economists to use their persuasiveness for the good of all (where 'good' is defined as persuaded more people to believe in economists' opinions).
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