Structure of the thesis

The remainder of the thesis can be categorised into three parts. The first part, comprising Chapters 2 and 3, provide the conceptual basis of the studies conducted in this thesis. Chapter 2 provides the contextual and theoretical foundations of the cost-benefit

7 _{DeShazo & Cameron (2005) examined a wide range of actual and expected morbidity in individuals’ demand}

for health risk mitigation with a stated preference survey. Bleichrodt, Crainich & Eeckhoudt (2003), Fujii & Osaki (2019), and Liu (2004) developed theoretical models that indicate individuals’ willingness-to-pay for health risk mitigation increases with the presence of comorbidity.

12

analysis of noise abatement policy. As outlined in Section 1.2, the information required to ascertain whether noise abatement policies result in a potential Pareto improvement includes the noise transfer and aggregating function, the marginal benefits of noise abatement, and the marginal costs of noise abatement. Hence, economics and acoustic engineering literature are reviewed. Gaps in the literature valuing the benefits noise abatement are identified.

Chapter 3 develops the research questions. The overarching aim of the research questions is to inform the design of noise abatement policies by providing an estimate of the marginal benefits of noise abatement. The research questions are derived from the gaps in the literature presented in Chapter 2.

Following the discussion of the conceptual basis and research questions, the second part of the thesis (spanning Chapters 4 to 6) describes the development and refinement of the survey questionnaire. Chapter 4 begins this discussion by presenting the random utility model, which forms the basis of the choice modelling methodology. The research design to answer the research questions outlined in Chapter 3 is also discussed.

Chapter 5 uses the theoretical framework introduced in Chapter 4 to design the survey questionnaires. To answer the research questions outlined in Chapter 3, two audio-based questionnaires were designed to estimate the marginal benefits of construction and road noise abatement. Further, a text-based questionnaire was designed to estimate the difference in willingness-to-pay for construction noise when respondents are presented with audio- and text- based questionnaires. The questionnaires also included questions to understand the heterogeneous preferences for noise abatement.

The survey questionnaires designed in Chapter 5 were refined by conducting a series of focus group discussions. Chapter 6 presents the design and findings from the focus group discussion. The focus group discussions provide insights into the disamenities caused by construction activity and roads as well as their preferences for noise abatement. Participants of the focus group discussions also reviewed the draft survey questionnaire. Findings from these discussions enable improvements to the survey questionnaire presented in Chapter 5 to be made. Feedback on the design of the choice sets is particularly important as the design of the choice set was novel.

The third part of the thesis, comprising Chapters 7 to 11, describes the results from the surveys. Chapter 7 begins the discussion of the results from the study by presenting the summary statistics from each phase of the survey. The demographic profiles of respondents are

13

presented and compared with the population in order to understand the representativeness of the survey sample. In order for stated preference surveys to elicit the true preferences of survey respondents, respondents must believe that the scenario provided in the questionnaire is realistic and that results of the questionnaire will affect future policies on noise abatement. Hence, protest respondents and respondents who did not think the survey was consequential are identified and the profile of these respondents are examined.

Chapter 8 is the first of four chapters analysing the results of the choice modelling surveys. This chapter presents the results of the regression analysis from the audio-based construction noise survey. Specifically, the marginal benefit of construction noise abatement is estimated with conditional logit and random parameter logit regression models. The estimated marginal benefits inform the cost-benefit analysis of publicly-provided construction noise abatement.

Chapter 9 compares the results from the audio-based survey presented in Chapter 8 with results from a text-based survey. As discussed in Section 1.3, the text-based survey described changes to noise levels textually and included test questions to ascertain respondents’ understanding of the information provided in the survey questionnaire. Comparisons of the results from the audio- and text-based surveys provide insights into the effect of respondents’ understanding of the survey questionnaire on their preferences for noise abatement.

Chapter 10 presents the results of regression analysis from the road noise surveys. Similar to the analysis conducted in Chapter 8, conditional logit and random parameter logit regression models were conducted to estimate the marginal benefits associated with road noise abatement. Results from the analysis provide information on the marginal benefits of road noise abatement. The estimated marginal benefits can, in turn, be used to inform cost-benefit analysis of publicly-provided road noise abatement.

Chapter 11 examines the heterogeneity in preferences for public provision of noise abatement. As discussed in Section 1.3, privately-provided noise abatement, hearing sensitivity, and distance between residences and construction sites or roads may affect preferences for noise abatement. Hence, the effects of these factors on the marginal benefits of noise abatement is estimated.

Chapter 12 concludes with a discussion of the main research findings presented in the thesis. This is followed by a discussion of policy recommendations as well as future areas of

14

research. Further, mechanisms to provide efficient levels of construction and road noise abatement are discussed and proposed as future work.

15