Estimation of Distance-Decay Functions to Account for Substitution and Spatial Heterogeneity in Stated Preference Research
通过选择实验检验环境改善支付意愿的空间异质性，发现距离衰减函数在用户与非用户及不同研究地点间存在差异，考虑空间趋势变量可揭示更多空间异质性，并显著影响支付意愿估计。
In a site-selection choice experiment various hypotheses are tested related to spatial heterogeneity in willingness to pay (WTP) for environmental improvements. Spatial heterogeneity is measured through distance-decay effects, substitute sites inside and outside the experiment’s choice set, and spatial trend variables. We demonstrate that distance-decay functions differ between users and nonusers and across study sites. Also the distance to substitutes outside the choice set explains spatial variation in WTP. We show that further extending the model with spatial trend variables reveals additional spatial heterogeneity in choices. Accounting for spatial heterogeneity patterns results in significantly different WTP estimates for environmental improvements. <i></i>