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

warming. True or False? 53.2 4.9 41.9 Note: This table reports the proportion of respondents providing correct, incorrect, and ‘‘do not know” answers to each of the ten environmental knowledge questions. Percentages may not sum up to 100 due to rounding. https://doi.org/10.1371/journal.pone.0263383.t007 PLOS ONE Green returns to education PLOS ONE | https://doi.org/10.1371/journal.pone.0263383 February 3, 2022 15 / 20

Table 7 summaries the responses to the environmental knowledge questions. In particular, it reports the proportion of respondents providing correct, incorrect and “do not know” answers to each of the ten environmental literacy questions. Overall, we observe a lack of envi- ronmental literacy among Chinese people. Most respondents could provide correct answers to the questions of automobile exhaust (81.2%) and abuse of fertilizers (83.6%), while the propor- tions of correct answers to the questions of acid rain, single species, domestic water pollution reports and air quality reports fail to exceed 50%. The question of domestic water pollution reports turns out to be the most difficult question for respondents, as the percentage of correct answer to that question (16.4%) is the lowest among the ten questions. Then, we construct an environmental knowledge score by awarding one point for each correct answer. Thereby the resulting score, Environmental knowledge, lies between 0 and 10. We relate this environmental knowledge score to educational attainment and report the results in Table 8. The coefficients on education are significantly positive, indicating that the level of education has a positive impact on environmental knowledge. This supports the notion that the education effects pass through environmental knowledge. Furthermore, we investigate the extent to which this mediating variable contributes to the effects of education on pro-environmental attitudes and behaviors. To achieve this goal, we

follow the literature [14,39] and perform a standard mediation analysis in which we assess how the coefficient of education changes when the mediating variable is added as controls to the regressions. Specifically, we compute the percent change in the magnitude for the coefficient of education when a particular mediator is added and interpret it as the proportion of effects of education that are explained by that mediator. Table 9 reports the results of the mediation analysis. We keep the sample in which all the variables are consistently available to ensure that the changes in the estimated coefficients across regressions are not driven by changes in the sample. Consequently, we end up with 3,401 observations for pro-environmental attitudes and 3,601 observations for pro-environ- mental behaviors. We report the corresponding benchmark estimates without the mediator in the columns (1) and (3) for the purpose of comparison. Columns (2) and (4) show the results when the variable Environmental knowledge is included as an explanatory variable. The Table 8. The effects of education on environmental knowledge. Environmental knowledge OLS 2SLS (1) (2) Education 0.191��� 0.340��� (0.013) (0.065) Controls Yes Yes Observations 3,601 3,601 First-stage estimation CSL 3.157��� (0.260) F-statistics 147.00 Note: The table reports the estimates from regressions of education on environmental knowledge. Column (1) uses OLS model for estimation, while column (2) uses 2SLS model for estimation. All regressions have the same controls

as in column (2) of Table 3, but their coefficients are suppressed for brevity. Robust standard errors are clustered at the cohort-city level and are reported in parentheses. ���, �� and � indicate 1%, 5% and 10% significance levels, respectively. https://doi.org/10.1371/journal.pone.0263383.t008 PLOS ONE Green returns to education PLOS ONE | https://doi.org/10.1371/journal.pone.0263383 February 3, 2022 16 / 20

variable Environmental knowledge has significant and positive effects on pro-environmental attitudes and behaviors. The addition of the environmental knowledge score in column (2) causes the coefficient of education to decrease from 0.012 to 0.007, indicating that 41.6% of the effect of education is explained by environmental knowledge. Similarly, we add the environ- mental knowledge score in column (4), resulting in a decrease in the magnitude of the coeffi- cient of education by 63.6%. Moreover, the estimated coefficients of education in columns (2) and (4) even become insignificant after controlling for the environmental knowledge. These results reveal that the mediator of environmental knowledge accounts for a large proportion of the effect of education. Hence, improved environmental knowledge is the important pathway through which education influences pro-environmental attitudes and behaviors. 6. Conclusions In this paper, we investigate whether educational attainment promotes pro-environmental attitudes and behaviors in China, using microdata from CGSS 2010. We first construct an atti- tude score and a behavior score using the responses to three questions regarding the willing- ness of their pro-environmental attitudes and six questions about the frequency of their pro- environmental behaviors, respectively. We establish causality by exploiting the exogenous vari- ation induced by the implementation of the Compulsory Schooling Law (CSL) in China. We find evidence that educational attainment is associated with higher levels of both pro-environ-

mental attitudes and behaviors. The estimates from 2SLS regressions reveal that an additional year of schooling results in an increase of 0.012 and 0.011 in the pro-environmental attitudes and behaviors, which are approximately 2.1% and 2% of the corresponding sample means. Moreover, we show that the positive effects of education on pro-environmental attitudes and behaviors are robust to various robustness checks and are heterogeneous across individuals. Furthermore, we focus on environmental knowledge as the major pathway underlying the Table 9. The part of education effects mediated by environmental knowledge. Pro-environmental attitudes Pro-environmental behaviors Base Base+ Environmental knowledge Base Base+ Environmental knowledge 2SLS 2SLS 2SLS 2SLS (1) (2) (3) (4) Part of effects can be explained 41.6% 63.6% Education 0.012�� 0.007 0.011�� 0.004� (0.004) (0.005) (0.004) (0.001) Environmental 0.013��� 0.019��� knowledge (0.003) (0.003) Controls Yes Yes Yes Yes Observations 3,401 3,401 3,601 3,601 First-stage estimation CSL 2.949��� 2.448��� 3.154��� 2.625��� (0.255) (0.257) (0.260) (0.261) F-statistics 133.44 90.61 146.58 101.50 Note: The table reports the results of mediation analysis. 2SLS models are used for estimation. As the potential mediator, environmental knowledge is added to the regressions in column (2) and in column (4), respectively. For the purpose of comparison, the results of base model without environmental knowledge are reported in

column (1) and in column (3). All regressions also control for the covariates in the basic model as in column (2) of Table 3. The coefficients on the control variables are suppressed for brevity. Robust standard errors are clustered at the cohort-city level and are reported in parentheses. ���, �� and � indicate 1%, 5% and 10% significance levels, respectively. https://doi.org/10.1371/journal.pone.0263383.t009 PLOS ONE Green returns to education PLOS ONE | https://doi.org/10.1371/journal.pone.0263383 February 3, 2022 17 / 20

relationship between education and pro-environmental attitudes and behaviors. We find that the acquisition of environmental knowledge is the channel that drives the effect of education on pro-environmental attitudes and behaviors. Our study offers crucial policy implications as well. Chinese government has been seeking to set the country on a path to more sustainable development, focusing on the effectiveness administrative and regulatory instruments [30]. Our study provides an alternative perspective. Specifically, increasing access to general education could be an essential and effective measure to motivate pro-environmental attitudes and behaviors among a broad population. In particu- lar, the effect of general education in promoting environmental knowledge is crucial for devel- oping countries such as China, where many people have low levels of environmental knowledge. Our study might have some limitations. First, our study is based on survey responses, which can suffer from measurement error problems. For example, well-educated people may be more likely to over-claim their pro-environmental attitudes and behaviors for keeping a good image. If this is the case, the effect of education on actual pro-environmental attitudes and behaviors might be overstated. In addition, partly due to data availability, we focus on the knowledge acquisition channel. There might exist other (coexisting) channels underlying the relationship between education and pro-environmental attitudes and behaviors. For example,

References 1. Xu P, Zeng Y, Fong Q, Lone T, Liu Y. Chinese consumers’ willingness to pay for green-and eco-labeled seafood. Food control. 2012; 28(1):74–82. 2. Zhang L, Wu Y. Market segmentation and willingness to pay for green electricity among urban residents in China: The case of Jiangsu Province. Energy Policy. 2012; 51:514–23. 3. Yu X, Lei X, Wang M. Temperature effects on mortality and household adaptation: Evidence from China. Journal of Environmental Economics and Management. 2019; 96:195–212. 4. Chen S, Guo C, Huang X. Air pollution, student health, and school absences: Evidence from China. Journal of Environmental Economics and Management. 2018; 92:465–97. 5. Tu M, Zhang B, Xu J, Lu F. Mass media, information and demand for environmental quality: Evidence from the “Under the Dome”. Journal of Development Economics. 2020; 143:102402. 6. Vlek C, Steg L. Human Behavior and Environmental Sustainability: Problems, Driving Forces, and Research Topics. Blackwell Publishing Inc Malden, USA; 2007. p. 1–19. 7. Steg L, Bolderdijk JW, Keizer K, Perlaviciute G. An integrated framework for encouraging pro-environ- mental behaviour: The role of values, situational factors and goals. Journal of Environmental psychol- ogy. 2014; 38:104–15. 8. Wang C, Wu J, Zhang B. Environmental regulation, emissions and productivity: Evidence from Chinese COD-emitting manufacturers. Journal of Environmental Economics and Management. 2018; 92:54–73. 9. Ponce P, Alvarado R, Ponce K, Alvarado R, Granda D, Yaguana K. Green returns of labor income and

human capital: Empirical evidence of the environmental behavior of households in developing countries. Ecological economics. 2019; 160:105–13. 10. Dee TS. Are there civic returns to education? Journal of public economics. 2004; 88(9–10):1697–720. 11. Albouy V, Lequien L. Does compulsory education lower mortality? Journal of health economics. 2009; 28(1):155–68. https://doi.org/10.1016/j.jhealeco.2008.09.003 PMID: 18976824 12. Banks J, Mazzonna F. The effect of education on old age cognitive abilities: evidence from a regression discontinuity design. The Economic Journal. 2012; 122(560):418–48. https://doi.org/10.1111/j.1468- 0297.2012.02499.x PMID: 22611283 13. Clark D, Royer H. The effect of education on adult mortality and health: Evidence from Britain. American Economic Review. 2013; 103(6):2087–120. https://doi.org/10.1257/aer.103.6.2087 PMID: 29533059 14. Black SE, Devereux PJ, Lundborg P, Majlesi K. Learning to take risks? The effect of education on risk- taking in financial markets. Review of Finance. 2018; 22(3):951–75. 15. Chankrajang T, Muttarak R. Green returns to education: Does schooling contribute to pro-environmen- tal behaviours? Evidence from Thailand. Ecological Economics. 2017; 131:434–48. 16. Wen LM, Rissel C, Baur LA, Lee E, Simpson JM. Who is NOT likely to access the Internet for health information? Findings from first-time mothers in southwest Sydney, Australia. International Journal of Medical Informatics. 2011; 80(6):406–11. https://doi.org/10.1016/j.ijmedinf.2011.03.001 PMID: 21493126

17. Liere KDV, Dunlap RE. The social bases of environmental concern: A review of hypotheses, explana- tions and empirical evidence. Public opinion quarterly. 1980; 44(2):181–97. 18. Lu S, Au W-T, Jiang F, Xie X, Yam P. Cooperativeness and competitiveness as two distinct constructs: Validating the Cooperative and Competitive Personality Scale in a social dilemma context. International Journal of Psychology. 2013; 48(6):1135–47. https://doi.org/10.1080/00207594.2012.743666 PMID: 23145818 19. Bybee RW. Scientific literacy, environmental issues, and PISA 2006: The 2008 Paul F-Brandwein lec- ture. Journal of Science Education and Technology. 2008; 17(6):566–85. 20. McCright AM. The effects of gender on climate change knowledge and concern in the American public. Population and Environment. 2010; 32(1):66–87. 21. Amore MD, Bennedsen M, Larsen B, Rosenbaum P. CEO education and corporate environmental foot- print. Journal of Environmental Economics and Management. 2019; 94:254–73. 22. Zhang P, Deschenes O, Meng K, Zhang J. Temperature effects on productivity and factor reallocation: Evidence from a half million Chinese manufacturing plants. Journal of Environmental Economics and Management. 2018; 88:1–17. 23. Chen X, Yang L. Temperature and industrial output: Firm-level evidence from China. Journal of Environ- mental Economics and Management. 2019; 95:257–74. 24. Ngobo PV. What drives household choice of organic products in grocery stores? Journal of retailing. 2011; 87(1):90–100. PLOS ONE Green returns to education

PLOS ONE | https://doi.org/10.1371/journal.pone.0263383 February 3, 2022 19 / 20

25. Mannberg A, Jansson J, Pettersson T, Bra¨ nnlund R, Lindgren U. Do tax incentives affect households׳ adoption of ‘green’cars? A panel study of the Stockholm congestion tax. Energy Policy. 2014; 74:286– 99. 26. Meyer A. Does education increase pro-environmental behavior? Evidence from Europe. Ecological eco- nomics. 2015; 116:108–21. 27. Zheng S, Kahn ME. Understanding China’s urban pollution dynamics. Journal of Economic Literature. 2013; 51(3):731–72. 28. Lutz W, Muttarak R, Striessnig E. Universal education is key to enhanced climate adaptation. Science. 2014; 346(6213):1061–2. https://doi.org/10.1126/science.1257975 PMID: 25430758 29. Card D. Estimating the return to schooling: Progress on some persistent econometric problems. Econo- metrica. 2001; 69(5):1127–60. 30. Ma G, Andrews-Speed P, Zhang J. Chinese consumer attitudes towards energy saving: The case of household electrical appliances in Chongqing. Energy Policy. 2013; 56:591–602. 31. Oreopoulos P, Salvanes KG. Priceless: The nonpecuniary benefits of schooling. Journal of Economic perspectives. 2011; 25(1):159–84. 32. Moretti E. Human capital externalities in cities. Handbook of regional and urban economics. 4: Elsevier; 2004. p. 2243–91. 33. McMahon WW. The social and external benefits of education. International handbook on the economics of education. 2004; 211:259. 34. Lange F, Topel R. The social value of education and human capital. Handbook of the Economics of Education. 2006; 1:459–509. 35. Maslow AH. New introduction: Religions, values, and peak-experiences. Journal of Transpersonal Psy-

chology. 1970; 2(2):83–90. 36. Inglehart R. Public support for environmental protection: Objective problems and subjective values in 43 societies. PS: Political Science & Politics. 1995; 28(1):57–72. 37. Xu C, Yang J, He L, Wei W, Yang Y, Yin X, et al. Carbon capture and storage as a strategic reserve against China’s CO2 emissions. Environmental Development. 2021; 37:100608. 38. Xie S, Mo T. The impact of education on health in China. China Economic Review. 2014; 29:1–18. 39. Huang W. Understanding the effects of education on health: evidence from China. 2015. 40. Cui Y, Liu H, Zhao L. Mother’s education and child development: Evidence from the compulsory school reform in China. Journal of Comparative Economics. 2019; 47(3):669–92. 41. Fang H, Eggleston KN, Rizzo JA, Rozelle S, Zeckhauser RJ. The returns to education in China: Evi- dence from the 1986 compulsory education law. National Bureau of Economic Research, 2012. 42. Liang Y, Dong Z. Has education led to secularization? Based on the study of compulsory education law in China. China Economic Review. 2019; 54:324–36. 43. Staiger DO, Stock JH. Instrumental variables regression with weak instruments. National Bureau of Economic Research Cambridge, Mass., USA; 1994. 44. Griliches Z. Estimating the returns to schooling: Some econometric problems. Econometrica: Journal of the Econometric Society. 1977:1–22. 45. Kotchen MJ, Boyle KJ, Leiserowitz AA. Willingness-to-pay and policy-instrument choice for climate- change policy in the United States. Energy Policy. 2013; 55:617–25.

46. Rummel RJ. Applied factor analysis: Northwestern University Press; 1988. 47. Angrist JD, Krueger AB. Instrumental variables and the search for identification: From supply and demand to natural experiments. Journal of Economic perspectives. 2001; 15(4):69–85. PLOS ONE Green returns to education PLOS ONE | https://doi.org/10.1371/journal.pone.0263383 February 3, 2022 20 / 20