Appendix I: Survey Method

The data in this report are based on a survey of 76,328 Facebook monthly active users, aged 18 and older. The survey was conducted February 17 – March 3, 2021. Sampled Facebook users saw an invitation to answer a short survey at the top of their Facebook Newsfeed and had the option to click the invitation to complete the survey on the Facebook platform.

The sample was drawn from the population of Facebook monthly active users, defined as registered and logged-in Facebook users who had visited Facebook through the website or a mobile device in the last 30 days.The Facebook monthly active users figure is reported in the company’s quarterly earnings report found on https://investor.fb.com. As of March 31, 2021, there were 2.85 billion monthly active users globally, including 259 million monthly active users in the US and Canada. Within each country or territory surveyed, we drew a sample in proportion to publicly available age and gender benchmarks. The sample population in the United States was drawn in proportion to the U.S. Census Bureau Current Population Survey 2018 March Supplement. All other countries and territories were sampled in proportion to data from the United Nations Population Division 2019 World Population Projections.

Data were weighted separately for each country and territory using a multi-stage, pre- and post-survey weighting process based on census and nationally representative survey benchmarks, Facebook demographics, and Facebook engagement metrics, balanced to the total number of survey completions.Weights were generated in three stages. First, we adjusted for sampling in proportion to age and gender census benchmarks. Second, we adjusted for non-response error using Inverse Propensity Score Weighting (IPSW) on Facebook demographics and Facebook engagement metrics to make the sample more representative of Facebook monthly active users. The Facebook monthly active user sampling frame constitutes a sizable proportion of the global population, but the proportion of adults who use Facebook differs from country to country. To more closely reflect the entire adult population in a country or territory, we used poststratification to publicly available nationally representative survey benchmarks, using weights from the first stages as inputs. The final weights were balanced to the total number of survey completions.

This project was a partnership between the Yale Program on Climate Change Communication and Facebook Data for Good. The survey instrument was designed by Anthony Leiserowitz, Seth Rosenthal and Jennifer Carman of Yale University, with support by Nicole Buttermore and Kelsey Mulcahy at Facebook. The survey was fielded by Facebook. The charts were designed by Xinran Wang and Jennifer Marlon of Yale University.

 

Rounding error and tabulation

Percentages are weighted based on general population parameters for each surveyed country and territory.

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., “I definitely would do it” + “I probably would do it”) are rounded after sums are calculated (e.g., 25.3% + 25.3% = 50.6%, which, after rounding, would be reported as 25% + 25% = 51%).

 

Sample size for surveyed countries and territories

The unweighted sample sizes for each country and territory are as follows:

  • Argentina (n = 2,450)
  • Australia (n = 2,668)
  • Brazil (n = 2,093)
  • Canada (n = 2,888)
  • Colombia (n = 2,040)
  • Costa Rica (n = 2,464)
  • Czech Republic (n = 2,431)
  • Egypt (n = 1,394)
  • France (n = 2,339)
  • Germany (n = 2,375)
  • India (n = 4,502)
  • Indonesia (n = 1,377)
  • Ireland (n = 1,483)
  • Italy (n = 2,554)
  • Japan (n = 2,747)
  • Malaysia (n = 1,125)
  • Mexico (n = 2,378)
  • Netherlands (n = 2,495)
  • Nigeria (n = 1,125)
  • Philippines (n = 1,126)
  • Poland (n = 2,446)
  • Russia (n = 2,568)
  • Saudi Arabia (n = 952)
  • South Africa (n = 1,512)
  • Spain (n = 2,319)
  • Taiwan (n = 1,918)
  • Thailand (n = 1,442)
  • Turkey (n = 1,712)
  • United Kingdom (n = 2,587)
  • United States (n = 13,555)
  • Vietnam (n = 1,263)