A Questionnaire Case Study of Chinese Opinions on the Haze ...

sustainability Article

A Questionnaire Case Study of Chinese Opinions on the Haze Pollution and Economic Growth Frederick Qiu 1 , Ethan Wang 2 , Matthew Fan 3 , Hong Liao 4 , Litao Wang 5 and Zuyi Huang 6, * 1 2 3 4 5 6

*

Central Bucks High School East, Doylestown, PA 18902, USA; [email protected] Central Bucks High School South, Warrington, PA 18976, USA; [email protected] Conestoga High School, Berwyn, PA 19312, USA; [email protected] School of Environmental Science and Engineering, Nanjing University of Information Science and Technology, Nanjing 210044, China; [email protected] Department of Environmental Engineering, Hebei University of Engineering, Handan 056038, China; [email protected] Department of Chemical Engineering, Villanova University, Villanova, PA 19085, USA Correspondence: [email protected]; Tel.: +1-610-519-4848

Received: 23 May 2018; Accepted: 4 June 2018; Published: 12 June 2018

Abstract: Haze pollution in China has reshaped daily life for the Chinese and led to serious health issues. At the same time, the Chinese have enjoyed the rapid economic growth that has contributed to this pollution. While questionnaire-based studies have been conducted within certain regions of China to learn the public’s opinions of haze pollution, little work has been done to understand how Chinese citizens value haze treatment in relation to their nation’s economic growth at a nationwide scale. To fill this knowledge gap, this project conducted a nationwide investigation of Chinese opinions on the benefits of economic growth versus the disadvantages of haze pollution, as well as their responses to efforts by the Chinese government to combat haze and to the influence of haze on Chinese daily life and on personal health. The study also sought suggestions for combatting haze. In particular, an anonymous questionnaire consisting of 29 questions was given in the summer and fall of 2017 to 1233 people of different genders, ages, child statuses, educational backgrounds, occupations, living areas (rural, suburban, and urban), and living regions. The statistical Chi squared test was then used to identify the demographic group of respondents supporting the economic slowdown policy or requesting more efforts from the Chinese government to combat haze pollution. A multivariate statistical approach—principal component analysis—was further applied to visualize respondents’ feedback on the impact of haze on their daily life and personal health, as well as the change of environment and economic conditions in the last 10 years. The results show that more than 50% of respondents, especially those with children, those between the ages of 31 to 50, and those living in high-pollution regions, supported the economic slowdown policy. Totally 40.63% of the entire group of respondents believed the government’s efforts to control haze were small or very small. Only 27.84% of respondents held the opposite opinions. In total, 72.91% of respondents believed the environment in China became worse or much worse in the past 10 years; however, most responded positively to the idea of resolving the haze issue within 15 or more years. Haze has caused health issues in and around half of the respondents and has significantly reshaped their outdoor activities. Keywords: haze pollution; statistical survey; principal component analysis; Chi squared test

1. Introduction The economic boom in China following the reforms introduced by Deng Xiaoping during the 1980s turned the country into a global powerhouse [1]. Specifically, while 27.6% of China was urbanized Sustainability 2018, 10, 1970; doi:10.3390/su10061970

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in 1992, this percentage increased to 52.6% in 2012 (cited from China Statistical Yearbooks). The Gross domestic product (GDP) grew by an average of 9% or more each year from the late 1980s to 2014 [2]. This economic growth in China is largely reliant on the large industries powered by fossil fuels, including steel factories. For instance, the 6.9% GDP growth in the second quarter of 2017 was largely due to the growth of the steel, coal, and cement industries, which are regarded as some of the most damaging industries for the environment [3]. China has developed as the top producer of coal in the world, producing 3.46 billion tons in 2016 alone, according to the Chinese National Bureau of Statistics. Coal is proven to be harmful to the environment: emissions due to coal often release mercury upon combustion [4–6]. Additionally, coal has contributed to 40% of all fossil fuel CO2 emissions [7]. The rapid infrastructure construction and urban expansion in China impose the highest demand for cement in the world. In particular, China produced around 57% of global cement production (i.e., 1.87 billion metric tons of cement) in 2010, with an average annual growth rate of 11.6% in cement production over the past two decades. China’s recent rapid industrial and urban growth has resulted in environmental complications such as the haze that is the focus of this study. A slight obscuration of the atmosphere by small solid or liquid particles, haze represents a form of air pollution that has become a prevalent concern in China, especially near city clusters [1]. Particles in the air with a diameter of less than 2.5 micrometers (so-called PM2.5 ) has caused 652,000 premature deaths in 2015 in 161 cities within nine regions across China, accounting for a total of 6.92% of all deaths that year [8]. The air quality in China as of the winter of 2016 has far exceeded dangerous levels, causing cancelled flights, closed schools, and poor visibility. While a concentration of 300 micrograms per cubic meter of PM2.5 particles is considered hazardous, 74 Chinese cities exceeded this number in 2013, with some even reporting numbers as high as 700 [9]. The problem posed by Chinese air pollution can no longer be ignored. The rapid economic growth that is driven by coal, steel, cement and other industries presents a growing contrast between the country’s economic and environmental goals. It is thus crucial to understand where the public stands on the issue because it can reveal to government policy makers and industrial owners the best course of action for implementing changes that will most effectively improve the quality of life for the Chinese populations. It may influence future economic endeavors that China can take on to maintain an environmentally sustainable but also economically successful nation. To address the aforementioned issues, this project presents a questionnaire to survey the opinions of the Chinese public on how they prioritize controlling haze pollution versus encouraging economic growth and their thoughts on efforts that might be made by the Chinese government to reduce haze pollution. Questionnaire survey approaches have been widely implemented as a means to obtain Chinese opinions on topics that are related to China’s haze pollution problem: (1) the annual consumption of various energy varieties (e.g., coal and fuel gas) in rural areas of northern China [10]; (2) tourists’ perception of haze pollution and the potential impacts on travel to Beijing in China [11]; (3) public awareness of smog pollution in China [12–16]; (4) the public’s willingness to pay (WTP) for reducing or tracking haze pollution [17–22]; (5) the public’s adaptive behavior responses to haze pollution in urban China [23,24]; (6) personal protection strategies from haze pollution [23,25]; and (7) consumers’ purchase intentions related to products that deal with haze pollution [26]. These studies indicate that the questionnaire-based survey is an effective approach for obtaining the public’s opinions on haze pollution in China. However, few of these studies have covered the topic of how far people are willing to go in sacrificing economic growth and halting the exacerbation of the environmental situation in China. This project aims to fill this knowledge gap. While several studies have been conducted to evaluate the government’s performance in responding to and controlling haze pollution [12,19], these were limited to either local areas (e.g., Xinjie, a rural area in central China) or specific populations (e.g., skilled workers). We revisit this question here by exposing it to more general populations with various demographic backgrounds (i.e., gender, age, child status, educational background, occupation, living area (rural, suburban, and urban), and living region in China). In addition, this work implements advanced multivariate statistics methods to extract important patterns from the wealth of data obtained through the 29-question survey, which includes


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seven demographics questions concerning gender, child status, age, education background, occupation, population density of the living area, and living region in China; 18 multiple choice questions surveying opinions regarding haze pollution and economic growth; three checklist questions (select all applicable answers); and one open-ended question asking for suggestions on battling the haze in China. The findings from this work can provide Chinese policymakers with information such as: (1) which demographic groups are satisfied/dissatisfied with the government’s performance in reducing haze pollution; (2) which demographic groups want to encourage/discourage slowing down economic growth to treat haze pollution; (3) a nation-wide investigation of the impact of haze pollution on Chinese daily life and public health; and (4) respondent’s suggestions on how to reduce haze pollution. 2. Materials and Methods 2.1. Questionnaire Design and Sampling The questionnaire designed for this project relied on psychometric paradigm methods [27,28]. The detailed decription of the questionnaire is provided as follows. The questionnaire includes the following topics: (1) respondents’ demographic information; (2) respondents’ opinions on the relationship between haze pollution and economic growth in China; (3) respondents’ comments on the treatment of haze pollution in China; and (4) the impact of haze pollution on respondents’ daily life and personal heath. The demographic parameters included in the questionnaire have been found important for studying people’s opinions on haze pollution. In particular, the respondent’s age, gender, education [24], living regions [14], and occupation [29] were found to play an important role in determining respondents’ opinions on haze pollution. The study presented in Reference [16] considered all these demographic parameters. The aforementioned demographic parameters were investigated in Questions 1–7. Specifically, Questions 1–3 surveyed general information of the respondents including their gender, age, and child status; Questions 4 and 5 ascertained the level of knowledge of the respondent by questioning his/her education and occupation; and Questions 6 and 7 determined the location and living area of the respondent. These questions allowed us to analyze the severity of haze pollution in different parts of China and analyze the concern and awareness of the problem by those who experience it firsthand. Questions 8–29 surveyed the respondent’s opinions on the experience with several issues regarding haze pollution versus the economic growth, haze pollution treatment, impact of haze pollution on the respondent’ daily life and personal health. In particular, Questions 8–12 studied the respondent’ opinions on quality of life and the environment pollution in China, including: whether the haze had negative impact on respondents’ life in the past 10 years (Question 8); how the environment changed in the past 10 years in China (Question 9); how the environment will change in China in the future (Question 10); how long the respondent thinks it will take for China to resolve the haze problem (Question 11); and how the respondent’ quality of life (with the consideration of both environment and economic conditions) has changed in the past 10 years (Question 12). Questions 13–17 further surveyed the respondent’s willingness to sacrifice economic growth in favor of controlling haze pollution: Question 15 asked about whether the government had done enough to combat haze; Question 16 was about whether the respondents supported potential policies that might slow down economic growth to work toward reducing haze pollution; and Question 17 listed options respondents could select to prioritize economic growth over reducing haze pollution or to prioritize reducing haze pollution over economic growth. Questions 18–22 were focused on haze pollution and its treatment, including: approaches for reducing haze pollution (Question 18); determinations of the global warming effect of haze pollution (Question 19); daily assessments by respondents to check the daily haze value, i.e., PM2.5 (Question 20); existence in the respondent’s city of haze pollution (Question 21); and possible troubles the haze may have caused in the respondent’s daily life or work (Question 22). Questions 23–28 collected information on the respondents’ personal experiences with haze pollution and the effects it had on the respondents’ families. Question 23 asked how much respondents had reduced their


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outdoor activities. Question 24 surveyed whether respondents changed their habits (e.g., taking buses instead of driving personal cars) due to the haze pollution. Question 25 studied whether respondents intended to leave if their city had haze. Question 26 investigated the approaches respondents used to protect themselves. Question 27 asked how often the respondents or their immediate families had contracted haze related health complications. Question 28 further studied the affected area in the respondents’ bodies if they got sick during periods of high haze pollution. Question 29 was an open-ended question that allowed respondents to input comments on haze pollution and thoughts on moving toward a sustainable environment in China. The questionnaire survey was mainly conducted through one of the most popular online surveying websites in China (www.diaochapai.com) and distributed through the most common social media apps (e.g., WeChat) used by Chinese. To make as many Chinese aware of this survey as possible, the survey was disseminated by local Chinese people from different educational backgrounds throughout different regions of China and to as many people as they knew. The questionnaire ultimately surveyed 1233 people in total, gathering the demographics of each respondent and their opinions on many different subjects concerning haze pollution and the Chinese economy. The samples were mainly collected in the summer and fall of 2017. Since the policies in China may change with time, the survey results may not reflect the latest opinions on haze pollution and economic growth. To get more complete (e.g., more samples) and timely Chinese opinions on these issues, questionnaires need to be manually and frequently handed to people living all over China. With the consideration of time, the legal permit, and the cost for conducting such a survey in China, we conclude that a more complete and timely survey can only be done by the Chinese government. Nevertheless, this work aims to provide a reference that reflects the opinions of some Chinese people on the haze pollution. 2.2. Statistical Analyses The survey data were analyzed to get the histogram for each of Questions 1–28. This can indicate the preference of respondents for the options listed for each question. Once the result for each question was shown, multivariate statistical methods, including Chi-squared test (CST) and principal component analysis (PCA), were further implemented to analyze respondents’ opinions on the key problems that this work was focused on. These problems are mainly related to respondents’ satisfaction on the government’s effort in preventing the haze pollution, respondents’ preference on slowing economics to prevent the haze pollution, and respondents’ opinions on the change in living environment, quality of life, and daily activities caused by haze pollution. In this work, the CST is mainly used to determine whether respondents’ opinions on Question 15 (i.e., whether the government had done enough to combat haze,) and Question 16 (i.e., whether respondents supported the policy to slow down economic growth for reducing haze pollution) are independent of their demographic backgrounds (i.e., gender, child status, age, educational background, occupation, population density of the living area, and living region in China). For example, Table 1 shows the results of respondents’ opinions on Question 16 based on their ages. The null hypothesis is that respondents’ opinions are independent of their ages. As for the respondents between the ages of 41 and 50 years, they take 35.5% (calculated by 438/1233) of the whole 1233 respondents. It is thus expected that 35.5% of the 669 respondents who support the policy should be between the ages of 41 and 50 years. This expected number, represented by nexpected,i in Equation (1), equals 237 (calculated by 35.5% × 669). It is observed from the table that there are actually 273 people between 41 and 50 years supporting the policy. The difference between this observed number (represented by nobserved,i ) and the expected number nexpected,i contributes one term in Equation (1) in the CST, i.e., (273 − 237)2 /237 = 5.47. The same approach is used to quantify the difference between the observed and expected numbers for other age categories so that all age categories are considered in the Chi-squared value (i.e., χ2 ). The Chi-squared value, along with the number of age categories (i.e., five age groups) and opinion categories (i.e., four different opinion, is then used as the input of the Chi-squared distribution to determine whether the difference is statistically significant.


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Typically, a p-value less than 0.05 is used to reject the null hypothesis (i.e., respondents’ opinions are independent of ages in this case). The command chisq.test in R was used in this work to perform the CST. Since the calculated p-value is 2.0 × 10−5 , much less than 0.05, it is concluded that the alternative hypothesis (i.e., respondents’ opinions depend on ages) is correct. A CST was performed for all demographic categories for Questions 15 and 16 in this project.

χ2 =

k

∑

i =1

nobserved,i − nexpected,i

2 (1)

nexpected,i

Table 1. The opinions of respondents to policy that would slow down economic growth to reduce haze pollution. Respondents’ Opinions of Policy That Would Slow down Economic Growth in Order to Reduce Haze Pollution

Ages

Total

No Support

Neutral

Support

No Opinion

Below 21 years 21 to 30 years 31 to 40 years 41 to 50 years Above 50 years

10 39 33 62 55

23 81 57 92 82

18 93 86 273 199

1 3 4 11 11

52 216 180 438 347

Total

199

335

669

30

1233

Note: the highlighted numbers in the table are used to illustrate the principal of the CST.

While the CST is used to identify the demographic groups who expect more efforts from the government toward haze prevention (Question 15) and who prefer to slow down economic growth for haze prevention (Question 16), principal component analysis is further used to visualize respondents’ opinions on the impact of haze pollution in respondents’ living environment, quality of life, and daily activities over the last few years. Principal component analysis (PCA) is one of the most commonly used multivariate statistical tools to analyze and visualize high-dimensional datasets [30,31]. The idea of PCA is to represent the original data using fewer new orthogonal variables called principal components that are obtained as linear combinations of the original coordinate variables. As shown in Figure 1, PCA can use a two-dimensional space that is represented by the first two principal components (i.e., PC1 and PC2) to present the original three-dimensional data. Each of individual principal components is essentially a linear combination of original coordinate variables. The essential idea of PCA is to rotate the original coordinate system so that the projections of the original data onto PC1 have the largest variance, which means that the PC1 can retain the largest portion of information from the original data. PC2 is orthogonal to PC1 and retains the second largest portion of information from the original data. Typically, the original data can be shown by the reduced dimensional space represented by the first few principal components. This explains why PCA has been widely used in high-dimensional data reduction and visualization. In this work, PCA was used to visualize the opinions of 1233 respondents on Question 8 (i.e., whether the negative impact on daily life was large), Question 9 (i.e., whether the environment became worse and worse in the last 10 years), Question 12 (i.e., whether the living quality, with the consideration of both economic and environment situations, became worse in the last 10 years), Question 22 (i.e., whether the haze pollution caused troubles in respondents’ work and daily life), and Question 23 (i.e., whether respondents reduced outdoor activities due to the haze pollution). The command prcomp in R, which is a popular programming language widely used in statistics analysis of statistical data [32] and data in engineering [33], was used to perform principal component analysis.

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Figure Figure 1. 1. An An illustrative illustrative diagram diagram for for principal principal component component analysis. analysis. The red color points points show show the the three-dimensional three-dimensional data, data, which which can can be be represented represented by by their their projections projections onto onto aa two-dimensional two-dimensional space space coordinated coordinated by by the the first first two two principal principal components components (i.e., (i.e., PC1 PC1 and and PC2). PC2). In In this this figure, figure, the the projects projects onto onto PC1 has higher variance than those onto PC2. PC1 has higher variance than those onto PC2.

3. 3. Results After the questions statistics, an overview the results for all questions in the survey is shown Whileanalyzing the survey along with of figures summarizing the results are shown in the below. This is followed by the of of respondents’ on Question 16 to studyisthe influence Supplementary Materials, an analysis overview the results opinions for all questions in the survey shown first from demographic parameters like age educational background on respondents’ opinions on below. This is followed by the analysis ofand respondents’ opinions on Question 16 to study the influence the policy that would slow down to combat haze. This is followed by respondents’ from demographic parameters like the age economy and educational background on respondents’ opinions on the satisfaction government efforts in haze prevention Question Whileby therespondents’ CST can be policy that with would slow down the economy to combat(i.e., haze. This is 15). followed applied to study questions, this in work mainly focused Questions and the 16, which were satisfaction with other government efforts hazeis prevention (i.e., on Question 15). 15 While CST can be seldom a nationwide China. To getfocused a comprehensive viewpoint applied studied to studyinother questions,scale this in work is mainly on Questions 15 and of 16,respondents which were on the change living environment, the To lifeget quality, and daily activities in the last few years, seldom studiedinintheir a nationwide scale in China. a comprehensive viewpoint of respondents on principal component analysis was used to the project for Questions 8, 9, few 12, 23 and the change in their living environment, life respondents’ quality, and feedback daily activities in the last years, 24 onto a two-dimensional space. from the impactfeedback of haze on principal component analysis wasFinally, used toresults project respondents’ forrespondents’ Questions 8,daily 9, 12,life 23 and and from respondents’ suggestions for combating were and personal 24 onto ahealth two-dimensional space. Finally, results from the impact haze of haze onpresented. respondents’ daily life and personal health and from respondents’ suggestions for combating haze were presented. 3.1. Overview of the Survey Results

3.1. Overview the were Survey Results for the demographic analysis of gender, child status, age, educational Questionsof1–7 designed background, occupation, the living area, and living China.status, Questions Questions 1–7 werepopulation designed density for theofdemographic analysis of region gender,inchild age, 8–29 then showed respondents’ opinions on the haze pollution and economic growth. Figures 2–29 educational background, occupation, population density of the living area, and living region in show theshowed survey results one byopinions one. Both and theand discussion of China.Questions Questions1–28 8–29and then respondents’ onthe thequestion haze pollution economic the resultFigures are given inshow the title of each 1–28 figure. The forresults Question wasthe anquestion open-ended growth. 2–29 Questions and theresult survey one29, by which one. Both and question for respondents to input their comments on the haze pollution, is shown in the Section 3.5. the discussion of the result are given in the title of each figure. The result for Question 29, which was

an open-ended question for respondents to input their comments on the haze pollution, is shown in the Section 3.5.


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Figure 2.2.The for 1 1“What The number males females Figure 2. result The result for Question 1“What “Whatisisyour yourgender?”: gender?”: The number ofof males andand females that that Figure The result forQuestion Question The number males females Figure 2. The result for Question 1 “Whatisisyour your gender?”: gender?”: The number of of males andand females that that responded to the survey were roughly equal. responded to the survey were roughly equal. responded to the survey were roughly equal. responded to the survey were roughly equal.

Figure 3. The result Question2 2“Do “Do youhave have children?”: Most respondents hadhad children, and only Figure 3. The result Question Most respondents children, and only Figure 3. The result Question 2 “Doyou you have children?”: children?”: Most respondents had children, and only 6.67% of respondents did not plan to have children. 6.67%6.67% of respondents diddid notnot plan totohave of respondents plan havechildren. children. Figure 3. The result Question 2 “Do you have children?”: Most respondents had children, and only 6.67% of respondents did not plan to have children.

Figure 4. The result for Question 3 “How old are you?”: There were more older people than younger

Figure 4. The result for Question “Howold old are you?”: you?”: There were more older people than younger Figure 4. The result forof Question 3 3“How people, with 63.66% the respondents being are above 40. There were more older people than younger people, with 63.66% of the respondents being above 40. people, with 63.66% of the respondents being above 40.

Figure 4. The result for Question 3 “How old are you?”: There were more older people than younger people, with 63.66% of the respondents being above 40.


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Figure 5. The result for Question 4 “What is your education background?”: The respondents were Figure 5. 5. The result for for Question Question 44 “What “What is is your your education education background?”: background?”: The respondents respondents were generally well-educated, with 82.88% having college diplomas or higher. generally well-educated, well-educated, with with 82.88% 82.88% having having college college diplomas diplomas or or higher. higher.

Figure 6. The result for Question 5 “What is your occupation?”: Office workers pulled ahead Figure 6. 6. The Question 55 “What “What is is your your occupation?”: occupation?”: Office workers pulled pulled ahead ahead Figure The result result for for Question Office workers numerically, making up 20.11% of the participants. numerically, making making up up20.11% 20.11%of ofthe theparticipants. participants. numerically,

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Figure 7. 7. The result for Question 6 “What “What area area (population (population density) density) do do you you live live in?”: in?”: Most of the the Figure Figure 7. The result for Question 6 “What area (population density) do you live in?”: Most of the people surveyed surveyed live live in in cities. cities. people people surveyed live in cities.

Figure 8. 8. The The result resultfor forQuestion Question7 7“What “Whatregion region China you in?”: It seems 67.40% of Figure ofof China dodo you livelive in?”: It seems thatthat 67.40% of the Figure 8. The result for Question 7 “What region of China do you live in?”: It seems that 67.40% of the respondents in northern, eastern, or northeastern China. respondents livedlived in northern, eastern, or northeastern China. the respondents lived in northern, eastern, or northeastern China.


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Figure The result for Question “What impact did haze have on your life in the past 10 years?”: Figure9.9.The Theresult resultfor forQuestion Question888“What “Whatimpact impactdid didhaze hazehave haveon onyour yourlife lifein inthe thepast past10 10years?”: years?”: Figure 28.39% of respondents stated that haze had aa medium level negative impact on their lives. Overall, 28.39% of respondents stated that haze had medium level negative impact on their lives. Overall, 28.39% of respondents stated that haze had a medium level negative impact on their lives. Overall, 22.47% of respondents said haze had big impact on their lives, and 18.82% stated had very large 22.47%of ofrespondents respondentssaid saidhaze hazehad hadaaabig bigimpact impacton ontheir theirlives, lives,and and18.82% 18.82%stated statedititithad hadaaavery verylarge large 22.47% impact. A small impact was selected by 18.57%, and very small impact was selected by 9.08%. impact.AAsmall smallimpact impactwas wasselected selectedby by18.57%, 18.57%,and andvery verysmall impact was selected by 9.08%. impact.

Figure 10. The result for Question 9 “How did the environment change in the past 10 years?”: 72.91% Figure Figure10. 10.The Theresult resultfor forQuestion Question99“How “Howdid didthe theenvironment environmentchange changeininthe thepast past10 10years?”: years?”:72.91% 72.91% of those surveyed stated that the environment had gotten worse or much worse in the past ten years. ofofthose surveyed stated that the environment had gotten worse or much worse in the past ten years. those surveyed stated that the environment had gotten worse or much worse in the past ten years.


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Figure 11. The The result result for for Question Question 10 “How will the environment change ininChina ininthe future?”: It Figure 10“How “Howwill willthe theenvironment environmentchange changein Chinain the future?”: Figure 11. 11. The result for Question 10 China the future?”: It is noted that 35.44% of people had negative prediction on the the potential potential for for improvement of of the It notedthat that35.44% 35.44%of ofpeople peoplehad hadaaanegative negative prediction prediction on on is isnoted the potential for improvement improvement of the the environment China, but 50.36% believed the environment would get better. environment environment China, China, but but 50.36% 50.36%believed believedthe theenvironment environmentwould wouldget getbetter. better.

Figure 12. The result for Question 11 “How long do you think Chinese can get haze resolved?”: 27.33% Figure 12. Question 11 “How longlong do you Chinese can getcan haze 27.33% Figure 12. The Theresult resultforfor Question 11 “How do think you think Chinese getresolved?”: haze resolved?”: of people believed that haze pollution in China would be solved in 5–10 years, with 8.52% of people of people believed that haze pollution in China would be solved in 5–10 years, with 8.52% of people 27.33% of people believed that haze pollution in China would be solved in 5–10 years, with 8.52% of choosing less than 5 years; 13.79% of people chose 10–15 years; 15.25% of people chose in 15–20 years; choosing less than 5 years; 13.79% of people chose 10–15 years; 15.25% of people chose in 15–20 years; people choosing less than 5 years; 13.79% of people chose 10–15 years; 15.25% of people chose in and 27.82% of people chose 20 years or longer to solve haze. and 27.82% people chose 20 years or longer to or solve haze. 15–20 years; of and 27.82% of people chose 20 years longer to solve haze.


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Figure Figure 13. 13. The Theresult resultfor for Question Question12 12 “How “How did did your your life life quality quality (with (with the the consideration considerationof of both both environment and economic conditions) in in thethe past 10 years?”: 49.07% and and 13.54% of people agreed that environment and economic conditions) past 10 years?”: 49.07% 13.54% of people agreed Figure 13. The result for Question 12 “How did your life quality (with the consideration of both quality of life (with the consideration of economic conditions) in the pastin years for the general population that quality of life (with the consideration of economic conditions) the past years for the general environment and economic conditions) in the past 10 years?”: 49.07% and 13.54% of people agreed that changed for the “better” and better”, respectively. Onrespectively. the contrary, On 15.9% quality of life said got population the“much “better” “much better”, thesaid contrary, quality of lifechanged (with thefor consideration ofand economic conditions) in the past years for the general15.9% population worse, and for 6.24%, it got much worse, while 11.92% said their life quality did not change. quality life got worse,and and“much for 6.24%, it got much worse, while 11.92% said said theirquality life quality changedoffor the “better” better”, respectively. On the contrary, 15.9% of lifedid got not change. worse, and for 6.24%, it got much worse, while 11.92% said their life quality did not change.

Figure 14. The result for Question 13 “Do you think the economic development is a prominent cause of haze?”: 53.12% of respondents agreed that economic development and haze are connected by Figure 14. 14. The result Question 13 13 “Do youyou think the economic development is a prominent cause Figure resultfor for Question “Do think the economic development a prominent causation. InThe contrast, 15.82% disagreed that economic development has led to haze is pollution, and of haze?”: 53.12% of respondents agreed that that economic development and and hazehaze are are connected by cause of haze?”: 53.12% of respondents agreed economic development connected 26.03% were neutral. causation. In contrast, 15.82% disagreed that economic development has led to haze pollution, and by causation. In contrast, 15.82% disagreed that economic development has led to haze pollution, 26.03% werewere neutral. and 26.03% neutral.


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Figure15. 15.The The result for Question 14 “Do you agree the haze pollution impair the economic growth?”: Figure 15. Theresult resultfor forQuestion Question14 14“Do “Doyou youagree agreethe thehaze hazepollution pollutionimpair impairthe theeconomic economicgrowth?”: growth?”: Figure 59.77% of respondents agreed that haze affected economic development, 12.65% disagreed thathaze haze 59.77%of ofrespondents respondentsagreed agreedthat thathaze hazeaffected affectedeconomic economicdevelopment, development,12.65% 12.65%disagreed disagreedthat that haze 59.77% affectedeconomic economicdevelopment, development,and and21.33% 21.33%were wereneutral. neutral. affected economic development, and 21.33% were neutral. affected

Figure 16.The Theresult resultfor forQuestion Question15 15 “Howdo do yourate ratethe thegovernment’s government’seffort effortin inhandling handlingthe thehaze haze Figure Figure16. 16. The result for Question “How 15 “How you do you rate the government’s effort in handling the pollution?”: 24.57% 24.57% believed believed national national efforts efforts to to control control haze haze were were small, small, and and 16.06% 16.06% believed believed the the pollution?”: haze pollution?”: 24.57% believed national efforts to control haze were small, and 16.06% believed efforts were very small, totaling 40.63% who believed efforts were small or very small. Overall, 17.11% efforts werewere very very small,small, totaling 40.63% who believed efforts efforts were small very or small. 17.11% the efforts totaling 40.63% who believed wereorsmall veryOverall, small. Overall, believed the theefforts efforts were were big, 6.73% 6.73%believed believed the the efforts were were very very big, big, for for aa total total of 23.84% who who believed 17.11% believed the effortsbig, were big, 6.73% believedefforts the efforts were very big, for a totalofof23.84% 23.84% who believed there was a large effort. Overall, 32.28% believed there was medium national effort. believed believedthere therewas wasaalarge largeeffort. effort. Overall, Overall,32.28% 32.28%believed believed there there was was medium medium national national effort. effort.


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Figure 17. The result for Question 16 “Do you support the policy of slowing down the economic Figure Figure 17. 17. The The result result for for Question Question 16 16 “Do “Do you you support support the the policy policy of of slowing slowing down down the the economic economic growth to reduce the haze pollution?”: 54.26% of respondents stood by a government policy that growth to reduce the haze pollution?”: 54.26% of respondents stood by a government policy that would growth to reduce the haze pollution?”: 54.26% of respondents stood by a government policy that would slow down economic growth to focus on haze policy and prevention. Overall, 27.17% were slow down growth to focus to onfocus haze on policy prevention. Overall, Overall, 27.17% were neutral, would sloweconomic down economic growth hazeand policy and prevention. 27.17% were neutral, anddisagreed 16.14% disagreed with such a policy. and 16.14% with such a policy. neutral, and 16.14% disagreed with such a policy.

Figure 18. The result for Question 17 “Which option do you agree to handle the economic growth Figure 18. The result for Question 17 “Which option do you agree to handle the economic growth Figure the 18. haze The pollution?”: result for Question “Whichagreed optionthat do ayou agree to handle the economic versus 76.32% 17 of people clean economic development plangrowth would versus the haze pollution?”: 76.32% of people agreed that a clean economic development plan would versus the haze pollution?”: of people agreed a clean plan would be the best course of action as76.32% a measure to control thethat haze. This economic is opposeddevelopment to 17.44% who believed be the best course of action as a measure to control the haze. This is opposed to 17.44% who believed be the best course of action as a measure to control the haze. This is opposed to 17.44% who believed that haze prevention should be vigorously managed before economic growth is considered, and only that haze prevention should be vigorously managed before economic growth is considered, and only that haze be vigorously managed before economic growth is considered, and only 2.35% whoprevention believed inshould an economy-first plan over environmental protection. 2.35% whobelieved believedin inan aneconomy-first economy-firstplan planover overenvironmental environmentalprotection. protection. 2.35% who


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Figure 19. The result for Question 18 “Which three approaches do you choose to handle the haze Figure Figure19. 19. The The result result for for Question Question 18 18 “Which “Which three threeapproaches approaches do doyou youchoose chooseto tohandle handlethe thehaze haze pollution?”:AAmajority majorityofof people supported need forincrease an increase in environmental awareness, pollution?”: people supported thethe need for an in environmental awareness, strict pollution?”: A majority of people supported the need for an increase in environmental awareness, strict environmental monitoring, the development clean and energy, and the adjustment of energy environmental monitoring, the development of clean of energy, the adjustment of energy structure. strict environmental monitoring, the development of clean energy, and the adjustment of energy structure. Specifically, 67.88% of those surveyed preferred the development of clean energy. Specifically, 67.88% of those surveyed development of clean energy. structure. Specifically, 67.88% of thosepreferred surveyedthe preferred the development of clean energy.

Figure 20. The result for Question 19 “Does the global warming affect the haze pollution?”: Almost Figure 20.The The resultfor for Question19 19 “Doesthe theglobal globalwarming warmingaffect affectthe thehaze hazepollution?”: pollution?”:Almost Almost Figure half the20. peopleresult (46.47%) Question thought that“Does climate change affected haze. halfthe thepeople people(46.47%) (46.47%)thought thoughtthat thatclimate climatechange changeaffected affectedhaze. haze. half


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Figure 21. The result for Question 20 “Are you concerned about the haze pollution (e.g., check daily PM2.5)?”: 91.40% 91.40%ofofthe the Chinese people were sometimes or concerned very concerned about and Chinese people were sometimes or very about the hazethe andhaze checked 2.5 value. checked PM daily PMdaily value. 2.5 2.5

Figure 22. The The result result for for Question Question 21 “Is there haze in the city you live in?”: Only Only 4.14% 4.14% said said that that there city, while while 50.20% 50.20% had had serious serious or or very veryserious serioushaze hazein intheir theircities. cities. was no haze in their city,


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Figure 23. The result for Question “Does haze cause trouble in your your daily daily life life or work?”: work?”: 74.13% Figure23. 23.The Theresult resultfor forQuestion Question2222 22“Does “Doeshaze hazecause causetrouble troubleinin 74.13%ofof of Figure your daily life ororwork?”: 74.13% those surveyed were affected in life and at work. thosesurveyed surveyedwere wereaffected affectedininlife lifeand andatatwork. work. those

Figure 24. The result for Question 23 “Does haze change your outdoor activities?”: 75.27% reduced Figure Figure24. 24.The Theresult resultfor forQuestion Question23 23“Does “Doeshaze hazechange changeyour youroutdoor outdooractivities?”: activities?”:75.27% 75.27%reduced reduced outdoor activity because of the haze. outdoor outdooractivity activitybecause becauseofofthe thehaze. haze.


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Figure 25. The result for Question 24 “Do you change your habits (e.g., taking buses instead of driving Figure 25. The result for Question 2424 “Do you change your habits (e.g., taking buses instead ofof driving Figure 25. The result for Question “Do you change your habits (e.g., taking buses instead driving personal cars) due to the haze pollution?”: 65.62% changed their habits to adjust to the haze. personal cars) due to the haze pollution?”: 65.62% changed their habits to adjust to the haze. personal cars) due to the haze pollution?”: 65.62% changed their habits to adjust to the haze.

Figure26. 26.The The resultfor forQuestion Question 25“Do “Doyou youintend intendtoto toleave leaveif if ifyour yourcity cityhas hashaze?”: haze?”:48.82% 48.82% ofthe the Figure result 2525 ofof Figure 26. The result for Question “Do you intend leave your city has haze?”: 48.82% the people did not know ifthey theywould wouldleave leavetheir theircity citybecause because ofthe thehaze, haze,but but33.98% 33.98%ofof ofthem themplanned planned people did not know if if ofof people did not know they would leave their city because the haze, but 33.98% them planned to leave. toto leave. leave.


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Figure 27.result The result for Question 26“Which “Which approachesdid did you use to to protect yourself (multiple Figure The result Question approaches did you use protect yourself (multiple Figure 27.27. The forfor Question 2626 “Which approaches you use to protect yourself (multiple options can be chosen)?”: Many people said they used an air purifier (46.07%), went out less (67.56%), options can chosen)?”: Many people said they used purifier (46.07%), went less (67.56%), options can bebe chosen)?”: Many people said they used anan airair purifier (46.07%), went outout less (67.56%), and wore masks (61.15%) to protect themselvesfrom from haze. haze. and wore masks (61.15%) protect themselves and wore masks (61.15%) toto protect themselves from haze.

Figure 28. The result for Question 27 “Did you or your family members get sick during the haze period?”: 45.66% of respondents had family that suffered from haze or suffered from it themselves, but another half did not.

Figure The result Question “Did you your family members sick during the haze Figure 28.28.The result forfor Question 2727 “Did you oror your family members getget sick during the haze period?”: 45.66% of respondents had family that suffered from haze or suffered from it themselves, period?”: 45.66% of respondents had family that suffered from haze or suffered from it themselves, but another half did not. but another half did not.


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Figure 29. The result for Question 28 28 “If“If you are areain inyour yourbody?”: body?”: 54.59% of Figure 29. The result for Question you aresick, sick,what whatisisthe the affected affected area 54.59% respondents were affected in their tracttract by haze. TheThe lungs andand eyes were thethe other of respondents were affected in respiratory their respiratory by haze. lungs eyes were othermajor where respondents areasmajor whereareas respondents got sick. got sick.

3.2. Respondents’ Opinions on Haze versus the Economic Growth

3.2. Respondents’ Opinions on Haze versus the Economic Growth Respondents’ feedback on Questions 13 and 14 indicated that more than 50% of respondents

Respondents’ feedback on Questions 13 and 14 indicated that more than 50% of respondents agreed agreed that the economic growth and the haze pollution were highly correlated, and that the rapid that the economic growth haze pollution highly correlated, and thatHere, the rapid economic economic growth was and one the of the major factorswere leading to the haze pollution. we further growth was one respondents’ of the majorpreference factors leading toeconomic the hazegrowth pollution. Here, further investigated investigated on rapid versus lowerwe haze pollution (i.e., respondents’ rapid economic growthopinions versus lower (i.e., economic Question 16). Question preference 16). The CSTon indicated that respondents’ on the haze policypollution to slow down growth to combat were dependent on their genders 1.06 × economic 10−3), their growth child statuses The CST indicated thathaze respondents’ opinions on the policy(p-value to slowofdown to combat −4 −5 − 3 of 1.37 × 10 on ), their ages (p-value(p-value of 1.98 × 10 ), and×the10regions they child lived in (p-value(p-value of 3.52 of haze (p-value were dependent their genders of 1.06 ), their statuses −4 Since the CSTs on respondents’ child andregions ages were of lived the smallest p-value, detailed 1.37 ×× 10 10−).4 ), their ages (p-value of 1.98 × 10−5statuses ), and the they in (p-value of 3.52 × 10−4 ). analysis of the results on these two demographic categories is given below. The results on Since the CSTs on respondents’ child statuses and ages were of the smallest p-value, detailed analysis respondents’ genders and living regions were then briefly summarized. of the results on these two demographic categories is given below. The results on respondents’ genders As shown in the previous section, 54.26% of respondents generally supported the policy to slow and living regions were then briefly summarized. down economic growth to combat haze (i.e., Question 16). This implied that Chinese people may be As shown the previous section, 54.26% respondents generally supported policy to slow willing to in sacrifice economic growth for a of better living environment. We furtherthe investigated downrespondents’ economic growth to combat haze (i.e., Question 16). This implied that Chinese people may opinions from different demographic groups (i.e., gender, child status, age, educational be willing to sacrifice economic growth forofathe better environment. Weshown further investigated background, occupation, population density livingliving area, and living region). As in Figure 30, 57.48% ofopinions those currently with children stated that they (i.e., would support government policy that respondents’ from different demographic groups gender, child status, age, educational slowed down the economy to preventdensity haze from is compared to the weakerAs support background, occupation, population ofworsening. the livingThis area, and living region). shown in coming from those planning to have children, only 39.51% of whom support the policy, and those Figure 30, 57.48% of those currently with children stated that they would support government policy not planning to have children, 45.69% of whom support the policy. For all three demographic groups, that slowed down the economy to prevent haze from worsening. This is compared to the weaker support coming from those planning to have children, only 39.51% of whom support the policy, and those not planning to have children, 45.69% of whom support the policy. For all three demographic groups, the percentage of people supporting the policy was much larger than the one opposing the

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the percentage of people supporting the policy was much larger than the one opposing the policy the of people supporting policy was much larger than the onethe opposing the policy andpercentage the one without preference (i.e.,the neutral). Among these three groups, respondents with and the one without preference (i.e., neutral). Among these three groups, the respondents with children were more supportive of government policies against haze. This is likely because the parents policy and the one without preference (i.e., neutral). Among these three groups, the respondents with children were more supportive of government policies against haze. This is likelychildren. because the were more stressed the health causedpolicies by hazeagainst pollution on their young Weparents further children were more by supportive ofissues government haze. This is likely because the parents were more stressed by the health issues caused by haze pollution on their young children. We further analyzed respondents’ opinions to Question 16 based on respondents’ ages (Figure 31). A majority of were more stressed by the health issues caused by haze pollution on their young children. We further analyzed respondents’ opinions to Question 16 based onthe respondents’ ages (Figure should 31). A majority of respondents between the ages of 31 and 50 believed that economic development be slowed analyzed respondents’ opinions to Question 16 based on respondents’ ages (Figure 31). A majority respondents between the ages of 31 and the 50 believed that(above the economic development should be slowed down to control the haze. However, older group 50 years old) or younger group (below of respondents between the ages offor 31 and 50 believed that the economic development should be down to control the haze. However, for the older group (above 50 years old) or younger group (below 30 years old), people were more reserved and were neutral about economic slow-down as a slowed down to control the haze. However, for the older group (above 50 years old) or younger 30 years old), people were more reservedthese and were neutral need aboutmore economic slow-down as ora government policy. This may be because respondents stable employment group (below 30 years old), people were more reserved and were neutral about economic slow-down government This may slowdown be becausemay these more employment or financial help.policy. While economic be respondents beneficial for need middle agedstable respondents in stable as a government policy. This may be because these respondents need more stable employment or financial help. While economic slowdown may be beneficial for middle aged respondents in stable lifestyles, thoseWhile just entering or about to leave thebeworkforce experience results.in stable financial help. economic slowdown may beneficialmay for middle agedadverse respondents lifestyles, those just entering or about to leave the workforce may experience adverse results. lifestyles, those just entering or about to leave the workforce may experience adverse results.

Figure 30. Grouping of support for potential government policy by respondents’ child status. The Figure 30. 30. Grouping Groupingofof support potential government policy by respondents’ child status. Figure support forfor potential government policy child status. The percentage on the Y-Axis represents the percent of respondents inby therespondents’ specific group. For example, The percentage on the Y-Axis represents the percent of respondents in the specific group. For example, percentage on the Y-Axis represents the percent of respondents in the specific group. For example, summing the percentages for all the bars representing people with children yield 100%. summing the the percentages percentages for summing for all all the the bars bars representing representing people people with with children children yield yield 100%. 100%.

Figure 31. Grouping of support for potential government policy by ages. Respondents were categorized Figure 31. Grouping of support for potential government policy by ages. Respondents were into five31. ageGrouping groups: 0–20, 21–30, 31–40, 41–50, andgovernment above 50. policy by ages. Respondents were Figure ofgroups: support for 21–30, potential categorized into five age 0–20, 31–40, 41–50, and above 50. categorized into five age groups: 0–20, 21–30, 31–40, 41–50, and above 50.


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Similar analysis was performed on respondents’ opinions on the economic-slowdown policy according respondents’ genders and living regions. While more than 53% of respondents in each of the female and male categories supported the economic-slowdown policy, 19.2% of the male respondents, versus 13.8% of female respondents, opposed the policy. That may be because husbands contribute to the major financial income in most Chinese families. As for living regions, respondents from East China (55.8%), North China (56.4%), Northwest China (64%), and Southwest China (59.0%) showed stronger support of the economic-slowdown policy than other regions. On the other hand, respondents from Northeast China (34.14%) showed the least support on the policy. Since economic growth in Northeast China has slowed down recently, it is understandable that people living there are against the economic-slowdown policy. 3.3. Respondents’ Opinions about the Government Effort in Haze Prevention A CST was performed for the seven demographic categories in Question 15 (i.e., whether the government’s effort in handling haze pollution was significant). It indicated that respondents’ opinions depended on their genders (p-value of 5.45 × 10−3 ), ages (p-value of 5.07 × 10−6 ), educational backgrounds (p-value of 1.45 × 10−5 ), occupations (p-value of 2.89 × 10−6 ), living area population density (p-value of 1.07 × 10−11 ), and living region (p-value of 2.2 × 10−16 ). As mentioned above, 40.63% of all respondents believed the government’s efforts to control haze were small or very small, which represented the largest portion of respondents in the five options of “very small effort”, “small effort”, “medium effort”, “large effort”, and “very large effort”. A sum percentage of larger than 40.63% in the options of “very small effort” and “small effort” thus indicates the corresponding demographic categories of respondents desired more government effort to combat haze pollution. This may indicate that Chinese people are expecting more effort from the Chinese government to control haze. The following demographic categories of respondents requested more efforts from the government in handling the haze pollution: female respondents in the gender category, respondents below 40 in the age category, respondents with bachelor or high-school degrees in the education category, respondents working as farmers, doctors, students, and regular company employees in the occupation category, respondents living in rural areas in the category of population density, and respondents from Northeast China, South China, and Southwest China in the category of living region. It is interesting to see in Figure 32 that people with a Bachelor’s degree or lower mostly said that the government was not doing much about the haze problem, while people with Master’s degrees were less inclined to respond that way. People with PhDs were evenly split in their responses. The respondents with higher education levels may know more about the (technical) challenges involved in reducing haze pollution in a short time frame and thus appreciate the government’s effort. While at first glance it may seem that the national environmental effort is small, a deeper understanding of the laws and regulations being implemented may reveal stronger efforts by the government to treat haze. People from areas with less severe haze pollution, such as rural residents and people from Northeast China, South China, and Southwest China, requested more government effort in handling the haze pollution. A potential reason for this is that most of the government’s policies on haze pollution were applied to those areas with severe haze pollution. Respondents not living in those areas thus may not feel the government’s effort in handling the haze pollution.



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Figure 32. Respondents’ opinion currentpolicies policies against haze according to their Figure 32. Respondents’ opinionon ongovernment’s government’s current against haze according to their educational backgrounds. educational backgrounds.

3.4.Impact The Impact of Haze Respondents’Daily DailyLife Life and and Personal 3.4. The of Haze on on Respondents’ PersonalHealth Health The following questions thesurvey surveyare are related related to of of haze on respondents’ dailydaily The following questions in in the tothe theinfluence influence haze on respondents’ life: Question 8 (i.e., whether the negative impact on daily life was large), Question 9 (i.e., whether life: Question 8 (i.e., whether the negative impact on daily life was large), Question 9 (i.e., whether the environment worsened progressively over the last 10 years), Question 12 (i.e., whether living the environment worsened progressively over the last 10 years), Question 12 (i.e., whether living quality—considering both economic and environmental situations—worsened over the last 10 years), quality—considering both economic environmental situations—worsened overand thedaily last 10 years), Question 22 (i.e., whether the hazeand pollution caused troubles in respondents’ work life), Question 22 (i.e., whether the haze pollution caused troubles in respondents’ work and and Question 23 (i.e., whether respondents reduced outdoor activities due to haze pollution).daily life), Respondents’ and Questionopinions 23 (i.e., on whether respondents outdoor activities due toFor haze pollution). these five questions reduced may be correlated to each other. instance, respondents agreeing haze pollution troubles in their work daily life (i.e., Respondents’ opinions on with thesethat fivethe questions may becaused correlated to each other. Forand instance, respondents Question may feelpollution that the negative of the on their life was large. 23) agreeing with23) that thealso haze causedimpact troubles in haze theirpollution work and dailydaily life (i.e., Question To project thethe opinions of respondents on haze thesepollution five questions, principal component analysis was the may also feel that negative impact of the on their daily life was large. To project implemented to identify a two-dimensional space defined by the first two principal components PC1 opinions of respondents on these five questions, principal component analysis was implemented to and PC2 that are orthogonal (or uncorrelated). Both PC1 and PC2 are the linear combination of the identify a two-dimensional space defined by the first two principal components PC1 and PC2 that are variables representing the respondents’ answers to the five questions. To facilitate the understanding orthogonal (or uncorrelated). Both PC1 and PC2 are the linear combination of the variables representing of the projections of original data onto the PC1-PC2 space, vectors representing respondents’ the respondents’ answers to the five Toinfacilitate understanding of the projections opinions of the five questions werequestions. also plotted Figure 33.the Vectors in similar directions indicate of original data onto the PC1-PC2 space, vectors representing respondents’ opinions of the five questions that respondents’ answers to those questions are correlated. For instance, respondents whose daily were life alsowas plotted in Figure 33.(Question Vectors in8)similar indicate that respondents’ answers to those impaired by haze tended directions to agree that haze caused troubles in their work and daily are life correlated. (Question 22). thought gotby worse much questions ForSimilarly, instance, respondents respondentswho whose dailythe lifeenvironment was impaired hazeor(Question 8) worse in the last 10 years (Question 9) tended to agree that life quality got worse (Question 12) and tended to agree that haze caused troubles in their work and daily life (Question 22). Similarly, tended towho reduce outdoor (Question 23). Theorpower principal component analysis is in respondents thought theactivities environment got worse muchofworse in the last 10 years (Question 9) its ability to visualize five-dimensional data so that we can get a more comprehensive view. In Figure tended to agree that life quality got worse (Question 12) and tended to reduce outdoor activities 33, bubbles were used to represent an assembly of respondents, with larger sizes indicating more (Question 23). The power of principal component analysis is in its ability to visualize five-dimensional respondents. For example, the large bubble along the direction of Question 8 indicated that many data so that we can get a more comprehensive view. In Figure 33, bubbles were used to represent an respondents agreed that the negative impact on their daily life was large. Similar, the respondents’ assembly of respondents, with larger sizes indicating more respondents. thethe large bubble opinions on other questions can be visualized in the figure. Figure 33 For alsoexample, shows that large alongbubbles the direction of Question many respondents agreed theThis negative are mainly located 8inindicated the sectorthat from vector Q#12 clockwise to that Q#22. meansimpact that on their respondents daily life was large. Similar, the respondents’ opinions otherand questions can be visualized generally agreed that the environment becameonworse that haze caused trouble inin the their daily33 life. Thisshows resulted in the reduced activities. Figure 34 shows the sector reduction of outdoor figure. Figure also that largeoutdoor bubbles are mainly located in the from vector Q#12 activities for respondents living in areas with different population densities (Q#23). Those living inworse clockwise to Q#22. This means that respondents generally agreed that the environment became and that haze caused trouble in their daily life. This resulted in reduced outdoor activities. Figure 34 shows the reduction of outdoor activities for respondents living in areas with different population


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densities (Q#23). living their in rural districts did not reduce theiras outdoor activity toin haze) as rural districts didThose not reduce outdoor activity (due to haze) much as those (due living urban much as those living in urban and suburban zones. and suburban Sustainability zones. 2018, 10, x FOR PEER REVIEW 24 of 30 rural districts did not reduce their outdoor activity (due to haze) as much as those living in urban and suburban zones.

Figure 33. Projections of respondents’ opinions on Q#8 (i.e., whether the negative impact on daily life Figure 33. Projections of respondents’ opinions on Q#8 (i.e., whether the negative impact on daily was large), Q#9 (i.e., whether the environment became worse and worse in the last 10 years), Q#12 life was large), Q#9 (i.e.,ofwhether the environment became worsethe and worseimpact in theonlast 10life years), Figure 33. Projections respondents’ opinions on Q#8 (i.e., whether negative daily (i.e., whether the living quality, with the consideration of both economic and environment situations, Q#12was (i.e.,large), whether the whether living quality, with thebecame consideration ofworse both in economic environment Q#9 (i.e., the environment worse and the last 10and years), Q#12 became worse in the last 10 years), Q#22 (i.e., whether the haze pollution caused troubles in situations, becamethe worse the lastwith 10 years), Q#22 (i.e.,ofwhether the haze caused troubles in (i.e., whether livinginquality, the consideration both economic andpollution environment situations, respondents’ work and daily and Q#23 (i.e., whether respondents reducedcaused outdoor activities became worse in the lastlife), 10 years), Q#22 (i.e., whether the haze pollution troubles in due respondents’ work and daily life), and Q#23 (i.e., whether respondents reduced outdoor activities due to the haze pollution) onto a two-dimensional space coordinated by the first two principal respondents’ work and daily life), and Q#23 (i.e., whether respondents reduced outdoor activities due to the haze pollution) onto a two-dimensional space coordinated by the first two principal components, components, i.e., PC1 and onto PC2. aBubbles represent an assembly of respondents, withprincipal larger sizes to the two-dimensional coordinated bylarger the first i.e., PC1 andhaze PC2.pollution) Bubbles represent an assembly ofspace respondents, with sizestwo indicating more indicating more respondents. representing questions are shownwith in White The components, i.e., PC1 and Vectors PC2. Bubbles representthe an five assembly of respondents, larger color. respondents. Vectors representing the five questions are shown in White color. The bubbles sizes show the indicating more respondents. Vectors representing the five questions are questions. shown in White color. The bubbles show the distribution of respondents’ opinions among the five distribution of respondents’ opinions among the five questions. bubbles show the distribution of respondents’ opinions among the five questions.

60.00% 60.00%

Percentage of Respondents


Question 23: How much change have you made Question 23: How much change have you made totoyour duetotohaze? haze? youroutdoor outdoor activity activity due 50.00% 50.00% 40.00% 40.00% 30.00% 30.00% 20.00% 20.00% 10.00% 10.00% 0.00%

0.00%

Not Applicable No Change at Small Change Some Change Major Change

Not Applicable No Change All at Small Change Some Change Major Change All Answer Choice

Answer Choice

Rural

Rural

Suburban

Suburban

Urban

Urban

Figure 34. The change of outdoor activities in respondents living in rural, suburban, and urban areas.

Figure 34. The change of outdoor activities in respondents living in rural, suburban, and urban areas. Figure 34. The change of outdoor activities in respondents living in rural, suburban, and urban areas. While Figures 5 and 6 show that respondents’ daily life was significantly influenced by haze, we further Figures studied 5the impact of that the haze pollution daily on respondents’ personal heath. Since most While and show respondents’ was significantly influenced by haze, While Figures 5 and 66show that respondents’ daily lifelife was significantly influenced by haze, we respondents werethe adults, the results shown below wereon notrespondents’ applied to young childrenheath. who generally we further studied impact of the haze pollution personal Since further studied the impact of the haze pollution on respondents’ personal heath. Since most most have weaker immune systems defend against As mentioned before, 45.66% of respondents were results to shown below werediseases. not applied applied to young young children children who generally generally respondents were adults, adults, the the results shown below were not to who respondents had family members suffering from haze, but another half did not (Question 27). A CST have weaker systems to defend againstagainst diseases. As mentioned before, 45.66% of respondents have weakerimmune immune systems to defend diseases. mentioned 45.66% indicated that respondents’ feedback was mainly dependent on theAs regions they livedbefore, in (Figure 35). of had family members suffering from haze, but another half did not (Question 27). A CST indicated that respondents had family members suffering from haze, but another half did not (Question 27). A CST Specifically, respondents living in Northeast China, South China, Southwest China, and East China respondents’ feedback wasor mainly dependent ondependent the they lived in they (Figure indicated respondents’ feedback was mainly the regions in Specifically, (Figure were that mostly unaffected affected relatively little by regions haze inon terms of health. On lived the 35). other hand, 35). respondents living in Northeast China, South China, Southwest China, and East China mostly respondents living in the moreinpolluted regions suchSouth as Northern, and Northwestern China Specifically, respondents living Northeast China, China,Central Southwest China, andwere East China unaffected or affected relatively little by haze in terms of health. On the other hand, respondents living more likely to beor afflicted by relatively health problems. Among respondents having issueshand, were were mostly unaffected affected little by hazethose in terms of health. Onhealth the other

in the more polluted as Northern, Central and Northwestern China were more China likely respondents living in regions the moresuch polluted regions such as Northern, Central and Northwestern were more likely to be afflicted by health problems. Among those respondents having health issues


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2018, 10, x FOR PEER REVIEW 25 of 30 to be Sustainability afflicted by health problems. Among those respondents having health issues during the haze periods, a majority (54.59%) of respondents had complications with their respiratory tracts (Figure 36). during the haze periods, a majority (54.59%) of respondents had complications with their respiratory Sustainability 2018,of x FOR PEER 25 of 30 In addition, 21.51% hadREVIEW lung problems. tracts (Figure 36).10, Inthem addition, 21.51% of them had lung problems.

during the haze periods, a majority (54.59%) of respondents had complications with their respiratory tracts (Figure 36).Question In addition, 21.51% of them had lung 27: How often haveproblems. you or your family

contracted haze related health complications?



Question 27: How often have you or your family

70.00% 60.00% contracted haze related health complications? 50.00% 70.00% 40.00% 60.00% 30.00% 50.00% 20.00% 40.00% 10.00% 30.00% 0.00% 20.00% Very Rarely Somewhat Often Very Often 10.00% Not Applicable 0.00%

Answer Choice

Not Applicable

Southwestern

Very Rarely

Southern

Central Southwestern Northern Southern Central

Northern

Somewhat Often

Answer Choice Northeastern

Very Often

Eastern

Northwestern Eastern Northeastern Northwestern

Figure 35. Grouping of frequency of haze related sickness by respondents’ living regions. Respondents Figure 35. Grouping of frequency of haze related sickness by respondents’ living regions. Respondents living in North China, Central China, and Northwest China suffered more in their health. 35. Grouping of frequency of haze related sickness by respondents’ living regions. Respondents living inFigure North China, Central China, and Northwest China suffered more in their health. living in North China, Central China, and Northwest China suffered more in their health.

Question 28: What regions of the body have Question 28: What regions in of due the body have you contracted illnesses to haze? you contracted illnesses in due to haze?

Respiratory Tract (such as sore throat) Respiratory Tract (such as sore throat)

Lungs (such as cough)

Lungs (such as cough)

Eye

Eye

Heart

Heart

Other Disease

Other Disease

No Sickness

No Sickness

Decrease in Immunity

Decrease in Immunity

Not Applicable

Not Applicable

0.00% 20.00% 30.00% 30.00% 40.00% 40.00%50.00% 50.00%60.00% 60.00% 0.00% 10.00% 10.00% 20.00% PercentageofofRespondents Respondents Percentage Figure 36.36. Areas health issues issueslikely likelycaused causedbyby haze. Multiple Figure Areasofofthe thebody bodyofofrespondents respondents having health haze. Multiple

Figure 36. Areas of be the body of by respondents having likely caused byfigure haze. Multiple choices choices could No sickness option shown the figuremeans means choices could beselected selected by respondents. respondents. No health sicknessissues option shown ininthe thethe couldrespondents berespondents selecteddid by respondents. No sickness option shown in the figure means the respondents did did not haveany anyillness illnessduring during the the haze periods. not have periods. not have any illness during the haze periods. While haze has reshapedChinese Chinesedaily dailylife life and caused inin China have found While haze has reshaped causedhealth healthissues, issues,people people China have found or created different solutionsfor forprotecting protecting themselves themselves during the haze attack (Question 26). Figure or created different solutions during the haze attack (Question 26). Figure While hazethat has67.56% reshaped Chinese daily combatted life and caused health issues, people in China have shows thepeople peoplesurveyed surveyed combatted haze another majority 37 37 shows that 67.56% ofofthe hazeby bygoing goingout outless lessand and another majority found or created different solutions for protecting themselves during the haze attack (Question 26). (61.15%) wore masks.Another Anothercommon common haze haze protection protection approach of of people was (61.15%) wore masks. approachused usedbyby46.07% 46.07% people was Figure 37 shows that 67.56% of the people surveyed combatted haze by going out less and another installing purifiersininhomes. homes. In In the the survey, survey, respondents multiple installing airairpurifiers respondents were wereallowed allowedtotochoose choose multiple approaches they used to protect themselves from haze haze. Therefore, respondents might simultaneously majority (61.15%) wore masks. Another common protection approach used by 46.07% of people approaches they used to protect themselves from haze. Therefore, respondents might simultaneously reduce outdoor activities, wear masks, and install air purifiers at home. was installing air purifiers in homes. In the survey, respondents were allowed to choose multiple reduce outdoor activities, wear masks, and install air purifiers at home.

approaches they used to protect themselves from haze. Therefore, respondents might simultaneously reduce outdoor activities, wear masks, and install air purifiers at home.


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Figure 37. Actions taken or items used by respondents to protect themselves from haze pollution.

Figure 37. Actions taken or items used by respondents to protect themselves from haze pollution. Multiple choices could be selected by respondents. Multiple choices could be selected by respondents. Figure 37. Actions taken or used by respondents to protect themselves from haze pollution. 3.5. Respondents’ Suggestions foritems Combating Haze Multiple choices could be by respondents. 3.5. Respondents’ Suggestions forselected Combating Haze

Although more than 35% of respondents did not think the environment in China would be better Although more than 35% respondents did not think the environment in China in the coming 10Suggestions years, more than 50% of respondents still expressed positive feelings aboutwould the be 3.5. Respondents’ forof Combating Haze improvement of the environment in China 10). Onstill the expressed other hand,positive more than 43% ofabout better in the coming 10 years, more than 50%(Question of respondents feelings Although more thanit35% respondents didlonger not think the environment in China would be China better respondents agreed willoftake 15 to resolve haze pollution the improvement of thethat environment in years Chinaor(Question 10). Onthe the other hand, issue moreinthan 43% of in the coming 10 years, more than 50% of respondents still expressed positive feelings about the (Questionagreed 11). This section shows theyears suggestions provided by respondents for handling haze respondents that it will take 15 or longer to resolve the haze pollution issue in improvement of the18 environment in Chinato(Question On thesolutions other hand, more thanthe 43% ofChina pollution. Question asked respondents select all 10). applicable for reducing haze (Question 11). This section shows the suggestions provided by respondents for handling haze pollution. respondents agreed will take 15 years or longer to by resolve the hazewere pollution issue in China pollution (Figure 38).that Theitmost popular solutions chosen respondents as follows: develop Question 18 asked respondents to select all applicable solutions for reducing the haze pollution (Question 11). This section shows the suggestions provided by respondents for handling new forms of clean energy (67.9% of respondents); design and strictly enforce environmentalhaze law pollution. Question 18 asked respondents to select all clean applicable solutions for reducing thenew haze (Figure 38). of The most popular solutions chosen by respondents were as follows: develop (67.7% respondents); increase the use of existing energy (63.5% of respondents); andforms pollution (Figure 38).of The most popular solutions chosen respondents were as follows: develop of clean energy (67.9% respondents); design and strictly enforce environmental law (67.7% of prioritize haze prevention policy (64.5% of respondents). Inby total, 45.2% of respondents thought that new forms of clean energy (67.9% of respondents); design and strictly enforce environmental law haze respondents); the energy use of existing cleanshould energyface (63.5% of respondents); prioritize companies increase with high consumption penalties. Only 25.5%and thought that (67.7% policy of respondents); increase thethe use of existing clean energy (63.5% of respondents); and with establishing organizations similar to United States Protection Agency in China prevention (64.5% of respondents). In total, 45.2%Environmental of respondents thought that companies prioritize haze prevention policy (64.5% of respondents). In total, 45.2% of respondents thought that beneficial for haze prevention, with even fewer people supporting strict regulation of the high would energybeconsumption should face penalties. Only 25.5% thought that establishing organizations companies with vehicles high energy consumption ofshould face(21.5% penalties. Only respectively). 25.5% thought that number of motor or the development real estate and 15.5%, similar to the United States Environmental Protection Agency in China would be beneficial for haze establishing organizations similar to the United States Environmental Protection Agency in China prevention, with even fewer people supporting regulation the number of motor vehicles would be beneficial for haze prevention, with strict even fewer peopleofsupporting strict regulation of theor the development real estate (21.5% 15.5%, respectively). number ofofmotor vehicles or the and development of real estate (21.5% and 15.5%, respectively).

Figure 38. Strategies selected by respondents for combatting haze. Multiple choices could be selected by respondents. Figure 38. Strategies selected respondents for for combatting combatting haze. choices could be selected Figure 38. Strategies selected bybyrespondents haze.Multiple Multiple choices could be selected by respondents. by respondents.



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While allowed respondents to select several suggested strategies for combatting While Question Question1818 allowed respondents to among select among several suggested strategies for the haze pollution, Question 29, which was an open-ended question, offered a chance for the combatting the haze pollution, Question 29, which was an open-ended question, offered a chance for respondents to input their own suggestions forfor haze the respondents to input their own suggestions hazeprevention/protection prevention/protection(Figure (Figure39). 39). The The most most popular comments given by respondents focused on the use of alternative vehicle transportation or popular comments given by respondents focused on the use of alternative vehicle transportation or the reduction of automobile exhaust. This was found in 39 responses. Many who were polled felt the reduction of automobile exhaust. This was found in 39 responses. Many who were polled felt that that industrial emissions were high. Suggestions included supervisionand andreduction reduction of of polluting polluting industrial emissions were tootoo high. Suggestions included supervision enterprises (36 mentions), complete shutdown of those polluting enterprises (13 mentions), and stronger enterprises (36 mentions), complete shutdown of those polluting enterprises (13 mentions), and governmental legislation and enforcement of pollution-preventing policies (30 mentions). The following stronger governmental legislation and enforcement of pollution-preventing policies (30 mentions). suggestions/comments were mentioned than eight respondents: a need for apublic The following suggestions/comments weremore mentioned moretimes than by eight times by respondents: need awareness (25 mentions), decreasing coal usage (18 mentions), afforestation (17 mentions), use of for public awareness (25 mentions), decreasing coal usage (18 mentions), afforestation (17 mentions), clean/renewable energy (15 mentions), reducing construction/infrastructure projects (11projects mentions), use of clean/renewable energy (15 mentions), reducing construction/infrastructure (11 decentralizing overcrowded urban population (10 mentions), enforcing effective waste treatment mentions), decentralizing overcrowded urban population (10 mentions), enforcing effective waste (9 mentions), and reshaping mentions). In terms of In general the haze treatment (9 mentions), and economic reshapingstructure economic(8structure (8 mentions). termssolutions of generaltosolutions issue, wasissue, unsurprising that most respondents endorsed theendorsed search and clean energy, to the ithaze it was unsurprising that most respondents theproduction search andofproduction of which, when replacing traditional energy gradually, can maintain the nation’s needs while fighting clean energy, which, when replacing traditional energy gradually, can maintain the nation’s needs haze. the number of cars the development real estate was not popular expected, while Controlling fighting haze. Controlling theornumber of cars or of the development of as real estate as was not as as this approach would require direct sacrifice on the part of respondents. Another trend observed popular as expected, as this approach would require direct sacrifice on the part of respondents. from respondents’ comments was the willingness of respondents to support a shift from traditional Another trend observed from respondents’ comments was the willingness of respondents to support fossil fuel emissions toward new renewable and efficient energy methods. All of these suggestions a shift from traditional fossil fuel emissions toward new renewable and efficient energy methods. All show that respondents were willing to seekwere change, minor orderand to suit the needs of of these suggestions show that respondents willing to and seekdrastic, change,in minor drastic, in order haze through decreased industrial pollution.industrial pollution. to suitprevention, the needs of haze prevention, through decreased

Figure 39. Suggestions from the public for haze prevention or protection. Figure 39. Suggestions from the public for haze prevention or protection.


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4. Discussion It is interesting to see from the results that most respondents supported the policy of slowing down economic growth to prevent the deterioration of the haze pollution. Certain respondents also suggested switching coal energy to clean energy so that China can still keep the rapid economic growth without causing more pollution. In addition, more than 40% of respondents expected more effort from the government in treating the haze pollution. All of these are helpful for the policy makers in China to make the right regulation on their economic and environmental policies. While tremendous effort was spent in outreach to as many respondents as possible in China, the sampled respondents may not completely reflect the opinions of most Chinese on the haze pollution and economic growth issues in China. In addition, questionnaires were mainly distributed via social media, and people living in remote areas with limited access to internet may not have been able to participate in the survey. As shown in Figure 34, urban residents changed their outdoor habits the most compared to their suburban and rural counterparts. This is because haze is most densely concentrated in industrial zones, which are often located near cities. Another issue is that the samples were mainly collected in the summer and fall of 2017. Thus, the results shown in this work mainly reflect the opinions of respondents in that period. To obtain the public’s opinion in a timely manner, the survey should be provided more frequently to more people in various locations across China. This can only be done by the Chinese government. Nevertheless, the obtained results can still provide a reference that reflects the opinions of some Chinese people on the haze pollution. Relating to the collected data itself, more analysis still needs to be performed. While a thorough breakdown of Questions 1–7 was conducted along with specific cases pertaining to the questions addressed in this study, the influence of the combination of these seven demographic questions on respondents’ opinions has not been thoroughly explored, which would be time-consuming and thus delay the publication of these timely survey results. 5. Conclusions This study presented the first nationwide investigation of Chinese opinions on economic growth in relation to haze pollution. It applied multivariate statistical methods to analyze questionnaire data from 1233 respondents. Most respondents agreed that rapid economic growth was one of the main causes of haze pollution. More than half of respondents supported a policy that would slow down economic growth to combat haze, especially the respondents that had children at the time of the study, that were aged 31–50, or that were living in regions with high haze pollution. The respondents who believed the government’s efforts to control haze to be small or very small outnumbered those with opposite opinions almost two times. CST showed that the respondents below 40 years of age, with Bachelor’s degrees or high-school diploma, working as farmers, doctors, students, and regular company employees, desired more effort from the government to control haze. Most respondents thought the environment became worse or much worse in the past 10 years. The haze pollution also significantly influenced their daily life and personal health, especially for the respondents living in the more polluted regions such as Northern, Central, and Northwestern China. Most respondents protected themselves from the haze pollution by going out less, wearing masks, and installing air purifiers in their homes. Most respondents were positive about the potential improvement of the environment in China, although most of them thought it would take more than 10 years to resolve the haze issue. Suggestions from respondents for reducing pollution included, but were not limited to: developing new forms of clean energy, designing and strictly enforcing environmental law, using alternative vehicle transportation to decrease automobile exhaust, prioritizing haze prevention policy, and regulating highly-polluting enterprises. There are many elements to explore that can develop from this project. The most obvious would be to obtain a larger sample. Certain demographics were not fully represented because there were not enough of respondents. This would need the support of the Chinese government. Nevertheless, this work serves as a starting point for getting a more timely and complete survey of Chinese opinions on haze pollution and its relation to economic growth.


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Author Contributions: Conceptualization, H.L., L.W. and Z.H.; Formal Analysis, F.Q., E.W., M.F. and Z.H.; Data Curation, all authors.; Writing-Original Draft Preparation, F.Q., E.W. and M.F.; Writing-Review & Editing, H.L., L.W. and Z.H.; Supervision, Z.H. Funding: This research received no external funding. Conflicts of Interest: The authors declare no conflict of interest.

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