Protest responses

Respondents who reject the policy scenario are termed protest respondents. These respondents fulfil two criteria simultaneously. First, protest respondents universally chose the status quo option. Second, respondents who universally chose the status quo option cited that they supported the implementation of noise abatement, but (i) did not think that they should be paying for the noise abatement measures and/or (ii) did not think that their payment will be effectively used to reduce noise. Respondents who universally chose the status quo option may have done so due to mitigating factors, such as budgetary constraints or they may not be adversely affected by noise pollution (Jorgensen et al. 1999). These respondents were not classified as being protest respondents. By comparison, protest respondents do not interpret the scenarios as intended and instead reject the proposed policy changes (von Haefen, Massey & Adamowicz 2005). These protest respondents do not reveal their true preferences.

0 5 10 15 20 25 30 35 40

Not annoying at all A bit annoying Annoying Very annoying Exceedingly annoying

157

Figure 7-7 illustrates the proportion of respondents who universally chose the status quo option. The laboratory survey yielded the lowest proportion of these respondents, where 12% of respondents universally chose the status quo option. By comparison, 40% of respondents to the construction noise field survey chose only the status quo option. This proportion increased to 64% among respondents to the text-based survey. Among respondents to the road noise field survey, around 43% of respondents only chose the status quo. Selection bias may have caused the lower incidence of respondents who universally chose the status quo option in the laboratory survey as compared to the other survey phases.

Respondents who agreed to participate in the laboratory survey had to invest time and effort to travel to the survey company’s venue. Consequently, respondents to the laboratory survey may have been more willing to choose alternatives to the status quo since they have already invested in the time and effort to participate in the survey. Nonetheless, since the preferences of individuals who declined to participate in the laboratory survey are not observed, reasons for the difference in the proportion of respondents who universally chose the status quo option cannot be identified.

Figure 7-7 Proportion of respondents who universally chose the status quo option

As discussed in Section 5.9.4, debriefing questions after respondents completed the choice sets sought to understand the reasons that cause a respondent to choose only the status quo option. The reasons provided by respondents are shown in Figure 7-8.

0 10 20 30 40 50 60 70

Construction, laboratory Construction, field Construction, field, (text-based) Road, field

158

Figure 7-8 Reasons for respondents choosing only the status quo option

The main reason respondents cited for choosing only the status quo option was that they supported the policy to reduce noise, but they did not think that they should pay for noise abatement. Respondents also cited concerns regarding the effective use of funds to provide noise abatement as well as about the efficacy of noise abatement measures. By contrast, only a small minority of respondents said that they chose the status quo option for all choice scenarios as they could not understand the choices they were asked to make. Across all phases of the survey, only 1.5% of respondents cited this reason. Consequently, reasons cited by respondents who universally chose the status quo option suggest that they understood the choice scenarios and chose only the status quo option as they felt the costs of implementing this policy should be borne by other parties.

After accounting for the reasons that respondents universally chose the status quo option, protest respondents were identified. The proportion of protest respondents in each phase of the survey is shown in Figure 7-9. In the laboratory survey, 7% of respondents were protest respondents. In the main audio- and text-based construction surveys, the proportion of protest

0 10 20 30 40 50 60 70 80

Construction, laboratory Construction, field Construction, field (text- based)

Road, field

% of respondents

I do not support noise reduction

The noise in the current location is not loud enough to adversely affect me

I support the policy to reduce noise, but I do not think that this policy will be effective

I support the policy to reduce noise, but the benefits of this policy are not worth the stated costs I support the policy to reduce noise, but I cannot afford the additional expense

I support the policy to reduce noise, but I do not think I should be paying for it

I support the policy to reduce noise, but I do not think the funds will be effectively used I found making a choice too confusing, so I always ticked the status quo

159

respondents was 22% and 23% respectively. Finally, in the road noise survey, the proportion of protest respondents was 26%.

Figure 7-9 Proportion of respondents who returned protest responses

In order to understand how demographic profiles affect the probability that an individual is a protest respondent, a logistic regression was estimated. The specification of the regression is as follows:

Pr(𝑝𝑟𝑜𝑡𝑒𝑠𝑡 = 1)_𝑖 = Λ(𝑋_𝑖𝛽 + 𝜀_𝑖) (7–1)

where Pr(𝑝𝑟𝑜𝑡𝑒𝑠𝑡 = 1)_𝑖 represents the probability that individual 𝑖 is a protest respondent. To estimate the regression, Pr(𝑝𝑟𝑜𝑡𝑒𝑠𝑡 = 1)𝑖 is a dummy variable taking a value of one if individual 𝑖 is a protest respondent and zero otherwise. 𝑋_𝑖 is a vector of demographic characteristics associated with individual 𝑖. Demographic characteristics included in the regression include age, gender, ethnicity, income, dwelling type, household size, and education attainment. 𝛽 is a vector of regression coefficients, 𝜀𝑖 is a random error associated with individual 𝑖, and Λ(∙) denotes the logistic function.

0 5 10 15 20 25 30

Construction, laboratory Construction, field Construction, field (text-based) Road, field

160

Table 7-4 Effect of demographic profile on probability of a respondent returning a protest response

(1) (2) (3) (4)

Construction noise Road noise

Laboratory Field Text-based Field

Age -0.00102 -0.000250 0.0187*** _0.01000** (0.00890) (0.00304) (0.00664) (0.00415) Female -0.469** _{-0.00408 -0.0980 -0.0701} (0.205) (0.0877) (0.196) (0.111) Ethnicity Malay -0.472 -0.446*** _0.633** _-0.208 (0.362) (0.140) (0.322) (0.182) Indian -0.348 -0.431*** _-0.751* _-0.275 (0.378) (0.157) (0.412) (0.217) Other -0.218 0.841 -0.203 (0.245) (0.697) (0.352) Private housing 0.148 0.225* _{-0.206 0.137} (0.272) (0.128) (0.235) (0.144) Income -0.00000413 -0.0000425** _{0.0000468 -0.0000524}* (0.0000299) (0.0000209) (0.0000360) (0.0000279) Household size 0.0830 -0.00162 -0.0917 -0.0137 (0.0743) (0.0150) (0.0660) (0.0382) Education attainment Post-secondary 0.225 0.0387 0.209 0.182 (0.300) (0.118) (0.268) (0.147) Bachelor’s degree or higher 0.286 -0.00615 0.574** _0.0433 (0.287) (0.127) (0.281) (0.170) Constant -0.895 -0.435** _-1.305*** _-0.836*** (0.562) (0.211) (0.482) (0.322) pseudo R2 _{0.054 0.022 0.091 0.027} AIC 228.0 1160.4 258.4 738.6 BIC 260.9 1214.4 294.9 787.0 Number of observations 199 1003 203 605

* _p<0.1, ** _p<0.5, *** _{p<0.01, robust standard errors are shown in brackets.}

Note: Age, Income, and Household size were continuous variables representing respondent’s age, income, and household size respectively. All other variables were dummy variables. Female was assigned a value of one if the respondent was female. The ethnicity variables, Malay, Indian, and Other, were assigned a value of one if a respondent was in that particular ethnicity. Other also took a value of one if the respondent did not state their ethnicity. The base ethnicity was Chinese. Other ethnicities were omitted in the construction noise laboratory survey as there was no within-group variation. Private housing took a value of one if the respondent lives in private housing. The base housing type was public housing. Post-secondary and Bachelor’s degree or higher took a value of one if the respondents completed up to post-secondary education (i.e., Junior College or Polytechnic) and university education respectively. The baseline education level was Secondary.

Results of the logistic regression are shown in Table 7-4. In the text-based construction survey and the road noise survey, older respondents were more likely to be protest respondents. Females were less likely to be protest respondents in the laboratory construction noise survey. Ethnicity had a statistically significant effect in the main audio- and text-based construction noise surveys. In both surveys, Indians were less likely to be protest respondents. Malays were less likely to be protest respondents in the audio-based survey but were more likely to be protest respondents in the text-based survey. Increased income was associated with a lower probability of protest in the main audio-based construction survey and the road noise survey. Living in private housing was associated with an increased probability of protest. Household size had no statistically significant effect on the probability that a respondent will be a protest respondent. Education attainment was only statistically significant for the text-based construction noise

161

survey. Respondents who attained university education were more likely to be protest respondents.

In order to ensure that regression estimates are not biased by protest respondents, researchers suggest exclusion of protest responses from the analysis (Edwards and Anderson, 1987; Milon, 1989). As such, the effect of protest respondents on the estimated average preferences from regression analysis are analysed in the following chapters.