Yale Program on Climate Change Communication

Appendix I: Methods

This report is based on findings from a nationally representative survey of 2,000 individuals in Indonesia (aged 18 years and above) conducted by the Yale Program on Climate Change Communication and fielded by an international survey company which has headquarters in Jakarta and more than 35 years of survey experience in Indonesia. Using a multi-stage probability proportional to size sampling method, approximately 100 sub-districts (Kecamatan) were randomly selected across 34 provinces in Indonesia. Within each Kecematan, urban (Kelurahan) and rural (Desa) areas were then randomly selected. Within each of those areas, approximately five households were randomly selected, and one respondent was randomly selected within each household. Respondents were recruited to participate in the questionnaire in-person, via door-to-door household interviews that occurred seven days per week (from 7 a.m. – 9 p.m.) from June 12 – July 16, 2025. If selected individuals were not available, interviewers made up to three callbacks to attempt to complete the interview. Interviews were conducted in person using Computer Aided Personal Interviewing (CAPI) via a tablet device. The average interview length was 43.6 minutes. Demographic parameters based on the 2022 Population Census data were used to create sampling targets. All target samples were achieved (refer to table below). The sample was weighted after completion of the data collection to adjust the final sample to match other (non-geographic) national demographic parameters (e.g., socio-economic status, age, gender). Interviews: 2,000 adults. Average margin of error: +/- 2.2 percentage points at the 95% confidence level.

In the data tables, bases specified are unweighted while percentages are weighted to match national population parameters. For tabulation purposes, percentage points are rounded to the nearest whole number. As a result, percentages in a given chart may total slightly higher or lower than 100%. Summed response categories (e.g., “strongly agree” + “somewhat agree”) are rounded after sums are calculated. For example, in some cases, the sum of 25% + 25% might be reported as 51% (e.g., 25.3% + 25.3% = 50.6%, which, after rounding, would be reported as 25% + 25% = 51%).

The survey instrument was designed by Anthony Leiserowitz, Jennifer Carman, Seth Rosenthal, Marija Verner, Emily Goddard, Emily Richards,and Jennifer Marlon of Yale University and Hilyatuz Zakiyyah of George Mason University. All graphics (including charts and tables) in this report were created by Emily Goddard of Yale University.