that the change in perceptions of norms evoked by their intervention continued to affect perceptions three to five months after exposure. That we were able to change norms in the short run suggests that continued exposure to such messaging (for example, in an ongoing public information campaign) is likely to change norms over the longer term.

Extrapolating from Bursztyn et al. (2020) suggests that our intervention could result in an increase in female labor force participation as large as 6 percentage points (12%) from the current FLFP rate of 53%. That is, an extra 3.5 million women working.

A further, and interesting, corollary of our findings is that in contexts where women’s support for working women (or any other social phenomenon) is underestimated - and the social norm is formed on the basis of observations of people’s behavior rather than stated preferences - empowering women to express their opinions would likely encourage adoption of a less conservative norm. Hence, empowerment of women’s voices is an alternative policy prescription to public information campaigns for changing social norms.

Finally, the paper makes a methodological contribution by demonstrating that real stakes outcome measures are needed to evaluate changes in norms. Twenty percent of our respondents were asked to make a hypothetical choice between the career-mentoring course and the shopping voucher. Unlike the real reward choices, hypothetical choices were significantly and overwhelmingly swayed by social-desirability bias. When the choice was hypothetical, individuals who were the most prone to social desirability bias - measured – via a 5-point Crowne and Marlowe (1960) scale were 28 percentage points (72% of the control mean) more likely to choose the socially-desirable career-mentoring course than those with the lowest social desirability bias scores. In contrast, when the stakes were real, social desirability bias had an insignificant effect on respondent choices. In the absence of real stakes, the interventions would have appeared ineffective.

# **2 Data Collection**

Data was collected in two online surveys. The first online survey covers 1,050 respondents (50% male, 50% female) residing in large urban centers throughout Indonesia.<sup>7</sup> The aim of the first survey was to measure social norms and people’s perceptions of these norms. We targeted respondents who were 18 to 40 years old, with at least a junior secondary education and who were married with at least one child aged under 18 years

> 7We sample from urban areas as previous research has shown the negative impact of marriage and childbirth on women’s labor force participation to be larger in urban areas where women are more educated, there are more job opportunities and women’s productivity is potentially higher, Cameron et al. (2019). Both surveys were conducted using Qualtrics’ online platform and with members of Qualtrics panel respondents who met our eligibility criteria, i.e., they lived in a metropolitan area, were married, aged 18-40 years, living with their partner, had children under the age of eighteen, and had at least junior secondary education. Metropolitan areas are those areas defined as such by the Centre for Urban Development and include Lampung, Bandung, Batam, Bekasi, Bogor, Depok, Makassar, Medan, Palembang, Pekanbaru, Semarang, Tangerang, and Jakarta. See the Regional Infrastructure Development Agency’s Strategic Plan 2020-2024: https://bpiw.pu.go.id/product/get ~~i~~ ndex/1.

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