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991.
992.
Paul D. Moskowitz William H. Medeiros Neal L. Oden Henry C. Thode Jr. Elizabeth A. Coveney Robert E. Rosenthal 《Risk analysis》1987,7(3):371-388
Experimental data were compiled for seven soybean varieties studied at four different locations in the U.S. for a period of one to three years. Three dose–response functions (linear, quadratic, and Weibull) were fitted, as appropriate, to the experimental data. Effects of acid deposition on soybean yields were estimated by combining variety-specific dose–response and production data. These calculations suggest that U.S. soybean production (2.2 billion bushels in 1982) would increase by 3.2 million bushels with a 10% reduction in 1982 hydrogen ion concentration levels in all counties where soybeans were grown, and by almost 70 million bushels with uniform improvement to pH 5.2. These estimates are based on many simplifying assumptions and are subject to several important sources of uncertainty explored in this study. The calculated changes are small in comparison with effects from other natural and anthropogenic stresses. 相似文献
993.
Benjamin H. Eichhorn Lakhbir S. Hayre 《Journal of statistical planning and inference》1983,7(4):307-316
We study a multiplicative randomized response method for obtaining responses to sensitive questions when the answers are quantitative. The method involves the respondent multiplying his sensitive answer by a random number from a known distribution, and giving the product to the interviewer, who does not know the value of the random number and thus receives a scrambled response. Some particular distributions for the random scrambling number are proposed and studied, and ways of generating the scrambling numbers are discussed. Some modifications for increasing the efficiency of the method are proposed, and numerical results are given that show the scrambled response method is generally superior to the previously used method of randomizing questions. 相似文献
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The California Agricultural Labor Relations Act (CALRA) evolved in the 1970s because the National Labor Relations Act (NLRA)
excluded agricultural workers. CALRA effectively placed the United Farm Workers Union in a stronger bargaining position vis-a-vis
farmers than the NLRA had done for industrial unions vis-a-vis nonfarm business firms. Society has suffered a net economic
loss from CALRA and the events preceding its enactment. Since passage of the act, at least three effects have been verified:
Relative to conditions that would otherwise have been expected to exist, consumers are facing higher prices; agricultural
workers are earning lower wages; and landowners have suffered losses in land values. 相似文献
996.
Typically in the United States only one contractor (the developer or first producer) makes a weapon system because it is too expensive or for some other reason infeasible to develop a second source. Congress and higher headquarters are constantly challenging the Armed Services to add other sources who can competitively make their systems. This paper describes a method of analyzing this complex problem which often has very large monetary and other significant impacts. Procedures and a case study are presented which consider cost and other criteria which might be used to make the second source decision. 相似文献
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