Economic Valuation of Nag-Aso Lake for Environmental Protection and Conservation in Albay, Philippines

This supplementary file provides comprehensive documentation supporting the study on the economic valuation of Nag-Aso Lake for environmental protection and conservation in Albay, Philippines. It is structured to ensure transparency, replicability, and methodological rigor. The document begins with detailed research instruments, including informed consent forms (English and Filipino), a structured household survey questionnaire, and guide questions for key informant interviews and focus group discussions. These instruments capture socio-economic characteristics, knowledge, attitudes, practices, and willingness to pay (WTP) for conservation. The file further presents a Likert coding framework and survey–variable mapping, clearly defining dependent and independent variables used in econometric analysis. It outlines how composite indices such as knowledge, attitude, practice, and environmental consciousness were constructed. The file also includes complete data processing procedures and analytical codes in STATA and R, covering descriptive statistics, logistic and ordinal regression models, multiple linear regression, and non-parametric Turnbull estimation. Finally, the document provides extensive regression results across multiple model specifications, offering empirical evidence on the determinants of WTP. Collectively, the file serves as a technical backbone of the study, enabling validation, replication, and deeper understanding of the analytical approach and findings.