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151.
In this article we compare three models of the stochastic behavior of commodity prices that take into account mean reversion, in terms of their ability to price existing futures contracts, and their implication with respect to the valuation of other financial and real assets. The first model is a simple one-factor model in which the logarithm of the spot price of the commodity is assumed to follow a mean reverting process. The second model takes into account a second stochastic factor, the convenience yield of the commodity, which is assumed to follow a mean reverting process. Finally, the third model also includes stochastic interest rates. The Kalman filter methodology is used to estimate the parameters of the three models for two commercial commodities, copper and oil, and one precious metal, gold. The analysis reveals strong mean reversion in the commercial commodity prices. Using the estimated parameters, we analyze the implications of the models for the term structure of futures prices and volatilities beyond the observed contracts, and for hedging contracts for future delivery. Finally, we analyze the implications of the models for capital budgeting decisions.  相似文献   
152.
Previous tests for structural changes (slope changes) and shifts (intercept changes) in the Phillips curve and union wage determination specify the date of structural change a priori. This article tests for structural changes and shifts without specifying the change point ex ante . The results support the belief that structural changes occurred in the early 1980s. Contrary to some previous research, however, the results do not support a structural shift in the Phillips curve.  相似文献   
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In this paper the role of expenses in explaining closed-end fund discounts is re-examined. A present value model is developed to illustrate the relationship between expenses and discounts. Earlier studies find that discounts are not related to management fees. In this paper, using a larger sample over a longer and different period and a better specification of the expense variable consistent with the model developed, discounts are found to be significantly related to expenses. The relationship between expenses and discounts holds in the presence of other control variables.  相似文献   
159.
This paper applies principles of transition to land tenure and squatting in South Africa. Political transition in South Africa reassigned political property rights, which produced contestable, and rent‐seeking incentives for squatting as a means to privatize land and redistribute wealth. Government failure to establish and protect private property rights in a squatter camp resulted in common‐pool problems that resisted private and public resolution with consequent rent dissipation and social loss. In response to this retreat from duty, informal agents emerged to claim their own share of the prize. Without enforceable rules of capture, the growth of squatter camps in South Africa will continue. JEL classification: D7, H8, K1, K4, R1, R4.  相似文献   
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