Green returns to education: Does education affect pro-environmental attitudes and behaviors in China?

to a college level, eighteen years to a graduate school education and beyond. Moreover, the CGSS data set collects detailed demographic information, which allows us to control for a range of confounding factors. Specifically, we control for Male, Married, Income, Employed, Han nationality, Rural, cohort fixed effect, and city fixed effect. Table 2 provides the defini- tions of variables of interest. Table 2 reports the descriptive statistics of the variables outlined above. The mean educa- tional attainment is 8.933 years, which suggests that on average the final degree that the respondents in our sample receive is merely junior high school. The majority of respondents are married, employed and belong to Han ethnic nationality. 47.3% of respondents are men and 48.8% live in rural areas. To have a preliminary view on how education relates to pro-environmental attitudes and behaviors, we plot the average educational attainment and the average pro-environmental Table 1. Summary of pro-environmental attitudes and behaviors. % of respondents Panel A: Pro-environmental attitudes Extremely unwilling to Reluctant to Do not care Willing to Extremely willing to To protect the environment, are you willing to pay higher prices? 7.8 25.4 20.2 37.3 9.4 To protect the environment, are you willing to pay higher taxes? 9.8 31.2 21.1 31.7 6.2 To protect the environment, are you willing to lower your standard of living? 12.6 33.7 19.6 28.6 5.4 Panel B: Pro-environmental behaviors Not at all Occasionally Frequently

How often do you separate wastes for recycling? 23.8 32.6 43.5 How often do you buy locally produced products or groceries without chemical fertilizers or pesticides? 32.0 37.7 30.3 How often do you buy environmentally friendly products marked with an environmental label? 34.1 41.6 24.3 How often do you reduce car usage for environmental protection? 28.8 44.4 26.9 How often do you cut down energy consumption for environmental protection? 27.1 40.3 32.7 How often do you cut down water consumption for environmental protection? 17.0 34.0 49.0 Note: Panel A reports the proportion of respondents providing “Extremely unwilling”, “Reluctant to”, “Do not care”, “Willing to” and “Extremely willing to” answers to each of the three pro-environmental attitudes questions. Panel B reports the proportion of respondents providing “Not at all”, “Occasionally”, and ‘‘Frequently” answers to each of the six pro-environmental behaviors questions. Percentages may not sum up to 100 due to rounding. https://doi.org/10.1371/journal.pone.0263383.t001 Table 2. Descriptive statistics. Variables Definition Obs. Mean Std. Dev. Median Min Max Pro-environmental attitudes The intensity of an individual’s pro-environmental attitudes 3,458 0.569 0.210 0.6 0.066 1 Pro-environmental behaviors The intensity of an individual’s pro-environmental behaviors 3,661 0.539 0.199 0.555 0.055 1 Education Years of schooling 3,661 8.933 4.607 9 0 18 Age Age in number of years 3,661 47.31 15.73 47 18 85 Male = 1 if male, = 0 otherwise 3,661 0.473 0.499 0 0 1

Married = 1 if married, = 0 otherwise 3,661 0.807 0.395 1 0 1 Income Ln (Personal income+1) 3,661 9.298 4.093 9.473 0 16.118 Han nationality = 1 if Han nationality, = 0 otherwise 3,661 0.918 0.275 1 0 1 Employed = 1 if employed, = 0 otherwise 3,661 0.629 0.483 1 0 1 Rural = 1 if rural, = 0 otherwise 3,661 0.488 0.500 0 0 1 CSL Exposure to implementation of the CSL 3,661 0.222 0.386 0 0 1 Environmental knowledge Number of correct responses to ten environmental knowledge questions 3,601 5.154 2.762 5 0 10 https://doi.org/10.1371/journal.pone.0263383.t002 PLOS ONE Green returns to education PLOS ONE | https://doi.org/10.1371/journal.pone.0263383 February 3, 2022 7 / 20