If the option is not exercised, the cost of contingent options will be zero.
如果不行使权利，或有期权持有者的成本为零。
2
Contingent valuation method (CVM) and travel cost method (TCM) now dominate these assessment studies, however the appraisal value content is actually different.
条件价值法和旅行成本法是当前较多采用的森林游憩资源价值评价方法，评价的价值内容却不同。
3
In this paper, some methods are introduced to value the forest products, such as hedonic method, travel cost, replacement cost and contingent valuation.