Estimating Nonmarket Values in Halong Bay, Vietnam: A View from Theory of Planned Behavior

Abstract

The lack of psychological factors in traditional CV model doesn’t only influence the explanation of payment behavior, but also it affects the accuracy of the WTP result, which is closely related to the policy making process for natural conservation and environmental improvement programs. Therefore, there is a need to link the psychological factors and to the payment behavior. This paper is started by discussion of some influential causes on validity and reliability of estimation results in traditional CV model, and then introduces a new model that is built from incorporating the theory of planned behavior (TPB) into the CVM. Linear regression model and hierarchical technique was applied for empirical analysis. The results of empirical analysis indicated that if WTP was identified as an expression of individual behavior, then it would be explained preferably by the theoretical framework of planned behavior while still conform to principles in the theory of consumer behavior. The results also shown that the WTP was not only affected by factors like income, cost, personal context, and attributes of environmental good in hypothetical market, but also it was influenced strongly and significantly by psychological factors. Regarding with the reliability of estimation result, this paper investigated that the CV result depends on the number and types of explanatory variables that put into the estimation model. The WTP value, for environmental quality improvement in Halong Bay, Vietnam, was US$0.60/ person/ trip. An extra charge might be added to the price of entrance ticket.

Keywords: Contingent valuation method, theory of planned behavior, psychological factors, validity and reliability.