[gyf304]

I believe the methodology is flawed.

> The business cards displayed the owner’s name and email address and we used fictitious but commonplace male names for each country.

This is assuming that email is a ubiquitous communication method in all countries, which is not true. USA has a very high email penetration rate, so does Japan (where all phones use email instead of SMS). On the other end of the spectrum, China's email penetration rate is less than 40% [1]. Business in China is conducted over WeChat and phone calls instead of email. If the person receiving the wallet does not have an email account, or doesn't even know what email is, I'd imagine the email contact rate to be quite low.

[1] https://www.twinova.com/email-dead-long-live-wechat/#:~:text....

[davetannenbaum]

A valid concern, but a couple points:

(1) This issue doesn't affect the treatment effect (the difference in return rates for money vs no money), which was the main focus of the paper. If email usage is low in a particular country, that should affect return rates equally in both the money and no money conditions.

(2) We've done a number of robustness checks on the point about email usage and have not been able to find evidence that it has a meaningful impact on the results. For instance, when looking at cross country differences in wallet return rates, the rank order correlation between the "raw" data and one that statistically adjusts for email penetration rates (based on World Bank data) is 0.95.

[gyf304]

Thank you for your reply.

Here are my thoughts on your 2 points.

(1) Noted. The main graphic emphasizes reporting rate over the delta, in both the axes selection and the ranking - and indeed the ranking is the main takeaway from many of the readers. If you rank by percentage delta of report rate, the graphic would be drastically different. This newer graphic wouldn't be "fair" either, as countries with higher control (no money) report rate would have a relatively low percentage delta.

(2) The World Bank Enterprise Survey data is listed under the title "Percent of firms using e-mail to interact with clients/suppliers" (for which China is at 85%) which I think is not the same as email penetration rate (which in the above reference in my parent comment, is at <40%). I understand your reasoning that cross country data is hard to come across.

I also read your reply in Science. I believe that while there are multiple limitations conducting the research - all perfectly reasonable - the limitations nonetheless affected the credibility of Fig. 1 - the main figure of the paper.

It is also mentioned in the reply that creating new social accounts is unfeasible. While I think this is true, wouldn't a single account per platform suffice? Most social platforms allow anonymity for display names / handles. If the social account name does not bear resemblance to an actual name, I don't think the participants would notice.