Author(s)

S. Mizokami & M. Parumog

Abstract

Stated choice experiments eliciting willingness-to-pay (WTP) for environmental goods and services provide the means to assign monetary estimates to the social and environmental costs of motor-vehicle use such as air pollution, noise and congestion. However, fixed parameter models indicating homogeneous WTP estimate dominates current applications. This paper investigates the need to account for heterogeneity in the WTP estimates of stated preference models involving an internet-based survey on the valuation of road and roadside environment in Metro Manila. Initially, factors affecting heterogeneity in WTP are investigated using contingent valuation (CV) data. Then, random parameter choice models are estimated to describe the effects of preference heterogeneity in attribute-based valuation data. Finally, the implications of value estimates on environmental policies for Metro Manila are presented. Keywords: environmental valuation, heterogeneity, random coefficient model. 1 Introduction Mobility improvements still play a vital role in the economic growth of many developing nations. However, high motorization rates as a consequence of increased mobility is triggering unaccounted environmental costs, such as air pollution, noise, congestion, accidents, and urban decay. In developing countries, concentration of total suspended particulate, recently linked with respiratory and cardiac diseases, is found to be many times higher than the World Health

Keywords

environmental valuation, heterogeneity, random coefficient model.