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991.
Robert Seckelmann 《保险科学杂志》2001,90(1):23-73
With the application of simple laws of logic to the clearly defined terms(capital) interest andinterest rate the rational dealing with interest-bearing money, the interest calculus, is derived followingLeibniz with present values, and according toEuler with future values. The procedure is determined by the equality in kind of the service rendered and the remuneration, the lending of money — a substitutable matter — as capital and the payment of money as interest for a certain time. With the addition of clear definitions of points and periods in time and of calculating with the accuracy of a day the rational dealing is a complete systems of rules compatible and coherent with other applications of mathematics and other situations in economics. It is logically simple, can easily be used with computers, and is suitable to serve as a basis for a transparent interest law, demanding and furthering clarity and truth, on a national and global level. The law claims the primacy of the rules of logic and nature over statute law, thecorpus juris, but it is not willing to base interest law on interest logic, interest calculus, it is not willing to admit the consequences of the equality in kind of capital and interest, the substitutability of money. It treats — for about the last 25 years with growing intensity —interest andinterest rate as word shells, to be filled with contents not to be subjected to matter-of-fact logic. Legal regulations, court decisions, scholarly opinions on using interest rates and calculating debts are full of contradictions to each other and in themselves. Theregula de tribus (the rule of three with linear conversion) is enforced wherever it is inappropriate. These circumstances are documented with examples from several states, with national, European and American regulations, and commented on with remarks by Leibniz, today as valid as in his time. 相似文献
992.
993.
Do Formula or Competitive Grant Funds Have Greater Impacts on State Agricultural Productivity? 总被引:1,自引:0,他引:1
This article examines the impact of public agricultural research and extension on agricultural total factor productivity at the state level. The objective is to establish whether federal formula or competitive grant funding of agricultural research has a greater impact on state agricultural productivity. A pooled cross-section time-series model of agricultural productivity is fitted to annual data for forty-eight contiguous states over 1970–1999. Our results show that public agricultural research and agricultural extension have statistically significant positive impacts on state agricultural productivity. In addition, Hatch formula funding has a larger impact on agricultural productivity than federal competitive grant funding, and a reallocation of Hatch formula funds to competitive grant funding would lower agricultural productivity. This seems unlikely to be a socially optimal policy. Furthermore, from a cost–benefit perspective, our study shows that the social marginal annualized real rate of return to public resources invested in agricultural research is 49–62%, and to public agricultural extension, the rate is even larger. 相似文献
994.
Robert F. J. Romain John B. Penson jr. Rémy E. Lambert 《Revue canadienne d'agroeconomie》1987,35(2):373-385
Among the different factors pertaining to the demand for durable inputs in agriculture, the way the input depreciates over time is an important issue. This study investigates four alternative capacity depreciation patterns for farm tractors. While published estimates from government agencies implicitly assume convex capacity depreciation patterns, the results of this study demonstrate that the use of agricultural engineering data which depict a concave rather than convex pattern better reflect farmers' investment decisions. An implicit rental price measure is also proposed to account for the fact that the purchase price of a durable input is not an appropriate measure of the implicit rental cost of the asset.
Parmi les facteurs déterminants de la demande pour les biens durables en agriculture, la rapidité avec laquelle I'intrant se déprécie est certainement importante lors des décisions d'investissement. La présente etude analyse quatre différents scénarios de dépréciation pour les tracteurs agricoles au Canada. Bien que les données publiées par les agences gouver-nementales supposent implicitement que les biens durables se déprécient à un taux annuel constant, les résultats de cette etude montrent que I'utilisation de données basées sur la valeur productive de I'intrant telle que calculée sur une base expkrimentale donne de meil-leurs résultats statistiques dans I'estimation de la demande pour les tracteurs agricoles. De plus, une mesure du coût implicite de I'intrant est également proposée pour tenir compte du fait que le prix d'achat n'est pas une mesure appropriée dans I'analyse de la demande pour un bien durable. 相似文献
Parmi les facteurs déterminants de la demande pour les biens durables en agriculture, la rapidité avec laquelle I'intrant se déprécie est certainement importante lors des décisions d'investissement. La présente etude analyse quatre différents scénarios de dépréciation pour les tracteurs agricoles au Canada. Bien que les données publiées par les agences gouver-nementales supposent implicitement que les biens durables se déprécient à un taux annuel constant, les résultats de cette etude montrent que I'utilisation de données basées sur la valeur productive de I'intrant telle que calculée sur une base expkrimentale donne de meil-leurs résultats statistiques dans I'estimation de la demande pour les tracteurs agricoles. De plus, une mesure du coût implicite de I'intrant est également proposée pour tenir compte du fait que le prix d'achat n'est pas une mesure appropriée dans I'analyse de la demande pour un bien durable. 相似文献
995.
Robert G. Chambers Tigran A. Melkonyan 《American journal of agricultural economics》2007,89(2):520-532
Optimal trade policy in an uncertain world is examined. Decision-maker attitudes toward uncertainty are represented in terms of the Gilboa–Schmeidler (1989) maximin expected-utility (MMEU) model. The central result is that in a two-country, general-equilibrium setting with both trading partners possessing an MMEU preference structure, Pareto optimality can require one trading partner to absorb all uncertainty in the economy if its set of priors is a subset of its trading partners. An immediate corollary is that autarky is Pareto optimal if the trading partner with the more inclusive set of priors either chooses or is endowed with a nonstochastic technology. 相似文献
996.
Patrick A. Jomini Robert R. Deuson J. Lowenberg-DeBoer Andr Bationo 《Agricultural Economics》1991,6(2):97-113
Soils in a large part of Niger's agricultural area are sandy and very low in nitrogen (N), phosphorus (P) and organic matter. This low soil fertility combined with low and erratic rainfall constitutes a severe constraint on food cropping in the area. Although agronomists have advised chemical fertilization as a means of improving soil fertility, little fertilizer has been used in this area of the world. The economic management of soil fertility in the agricultural area of Niger is analyzed using a dynamic model of farmer decision-making under uncertainty. The model is based on agronomic principles of plant growth and accounts for the carry over of P, an immobile nutrient. At current input prices, a soil P content of at least 14 ppm is found to be desirable. This target is above the natural soil fertility level of about 3 ppm. It can be maintained with a moderate annual application (12 kg P2O5 ha?1) of simple superphosphate. Results also suggests that returns to N fertilization are too low and variable to warrant the use of this input. 相似文献
997.
This study investigates the role of risk in farmers' acreage decisions for major field crops in the North Central region by revisiting an earlier study by Chavas and Holt. The empirical model is forward-looking and reflects better variable measurement. We test the effects of wealth and revenue risk on supply response. Estimated results are also used to examine the production impact of counter-cyclical payments (CCPs). We find that the effects of risk on supply response are not strong. An increase in initial wealth would lead to greater crop acreage, consistent with decreasing absolute risk aversion. The effect of CCPs on production appears to be negligible. 相似文献
998.
999.
1000.
Erwin Bulte Daan P. van Soest G. Cornelis van Kooten & Robert A. Schipper 《American journal of agricultural economics》2002,84(1):150-160
Stochastic dynamic programming is used to investigate optimal holding of primary tropical forest in humid Costa Rica when future nonuse benefits of forest conservation are uncertain and increasing. The quasi-option value of maintaining primary forests is included as a component of investment in natural capital. Although the impact of uncertainty on conservation incentives is substantial, our results indicate that a rising trend in future benefits and compensation by the international community for beneficial spillovers are more important factors in determining optimal holdings of forest stocks. Without compensatory payments, however, further deforestation may be warranted. 相似文献