Pei-Ing Wu

This study formulates a general model to account for the protest responses and no-answer replies. The distinct characteristics of this model are general in three ways: simultaneously accounting for protest and no-answer responses, applicable to all kinds of elicitation formats in contingent valuation, and simplicity in estimation. Creation of inverse Mills ratio is the distinctive step in this general model. The inverse Mills ratio is continuously carried in the subsequent estimation for the modification of different types of elicitation formats in this general model. The results generally indicate that these ratios are significantly different from zero. This means that accounting for these Mills ratios does have an important role in such modification when protest responses and/or no-answer responses are both taken into account. The results show that overall total willingness to pay from the general model with inclusion of protest and no-answer responses under different types of elicitation formats are higher than those estimated by traditional treatment. The degree of underestimation of traditional treatment is between 26% and 67%. That is, the general model proposed here for treating protest and/or no-answer responses in contingent valuation method can account for the full information, which might be potentially omitted or inappropriately dealt with in the estimation.

This study aims to investigate the relationships between economic development and environmental degradation regarding the emissions of CO₂ and SO₂ in Southeast Asia (SEA). The pooling data consist of 10 countries, Brunei, Cambodia, Indonesia, Laos, Malaysia, Myanmar, Singapore, the Philippines, Thailand, and Vietnam, in the period 2003-2012. Furthermore, income elasticity of CO₂ and SO₂ emissions is computed for each country to observe the sensitivity of environmental degradation through the emissions of CO₂ and SO₂ brought by economic development.
The results indicate that CO₂ displays an inverted U-shape pattern, whereas SO₂ has decreased at an increasing rate since 2003. It is expected that SO₂ will increase as the SEA economies further develop. The turning points for both CO₂ and SO₂, indicate that the current SEA income level has not reached the turning point. The income elasticities show that income elasticities for CO₂ are positive for all 10 countries. Both Singapore and Malaysia are classified as countries with high income. However, Singapore, with 0.64%, has the highest income elasticity, and Malaysia, with 0.15%, has the second lowest. There is no indication that wealthy countries have a significant impact on CO₂ through economic development. Income elasticities for SO₂ of each country are all negative. This suggests that SO₂ is an inferior good. Brunei, with 8.41%, has the most sensitivity toward change in SO₂ emissions, whereas Myanmar, with only 0.58%, is the least sensitive to SO₂ emissions.