Study On Optimum Extraction Of Exhaustible Resources Under Uncertainty

Exhaustible resources will be run out when man continues to exploit the resources. The process of resources extraction is a depletion process of resources. Because of some uncertainty, such as reserve uncertainty and emergence of backstop technology, the study on optimal extraction of exhaustible resources is becoming very complex. This dissertation discussed optimal extraction of exhaustible resources under uncertainty by using the theory and method of optimization.This paper enlarges the existing kinds of uncertainty. Based on reviewing literatures in this area, the sources of uncertainty systemically are examined from resources market. In accordance with these sources, uncertaint problems were classified into supply uncertainty, demand uncertainty, price uncertainty, market imperfect and policy uncertainty. It improves the existing classification of uncertainty.When the remaining stock does effect on the cost function, price trend is not clear even under competitive market. Here the trend of price change is deduced in theory. The optimal extraction models of exhaustible resources are built under market imperfect. Comparing the optimal price paths of resources, the result is found that monopoly often leads to underexploitation and common property often leads to overexploitation.The paper discussed optimal extraction of exhaustible resources under stock uncertainty. Extraction recovery rate is an important parameter of stock uncertainty. And firms can increase recovery rate by invesing to improve the level of management and technology. As a result, wasted resources can be decreased. Then firms are divided into two kinds by their aims which are to consider waste resources or not. It shows that the firms, which don't consider waste resources, often invest shortly. Then optimal extraction path was founded with adjusted recovery rate dynamically using optimal control theory. By setting some Scenario, strategies of adjusting recovery rate of coal is provided.In the paper, it is assumed that arrival date of a new technology is uncertaint. The accuracy of the proposition, which is "the more optimistic of estimating the development of new technologies, the more resources are extracted inducing more fast depletion of such resources", is tested in theory. It is found that the proposition is supported during the early date of resources extraction and the accuracy rate is depended on the size of resources reserves. The optimal extration paths were analyzed under policy expectation and parameter uncertainty. In view of probability space, the state of policy expectation was described, and the date of the state chang is found. Parameter uncertainty was described by timing uncertainty of resources tax reform. Then two main means of tax reform was considered in the papers, which is taxes rate improving and levy means changing. Using dynamic optimization theory, the corresponding optimal extraction models are built and the optimal extraction paths are found. The effectiveness of the ways of tax reform to protect resources is compared. The results show that the policy expectation can help protect the resources. By adjusting parameters the impact can be reinforced. Then the method of policy expectation in order to extract effectively, and expected taxation is designed to correct these unsuitable extraction behaviors. This provides an idea to resolve two or more uncertaint problems for other researchers.