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191.
For a balanced two-way mixed model, the maximum likelihood (ML) and restricted ML (REML) estimators of the variance components were obtained and compared under the non-negativity requirements of the variance components by L ee and K apadia (1984). In this note, for a mixed (random blocks) incomplete block model, explicit forms for the REML estimators of variance components are obtained. They are always non-negative and have smaller mean squared error (MSE) than the analysis of variance (AOV) estimators. The asymptotic sampling variances of the maximum likelihood (ML) estimators and the REML estimators are compared and the balanced incomplete block design (BIBD) is considered as a special case. The ML estimators are shown to have smaller asymptotic variances than the REML estimators, but a numerical result in the randomized complete block design (RCBD) demonstrated that the performances of the REML and ML estimators are not much different in the MSE sense. 相似文献
192.
193.
Abstract . The problems and contradictions which arise when an economically “poor” region is mandated to remain environmentally “pure“ are examined. The Adirondack region of New York State is such an area, being now protected by the 1972 Adirondack Park Land Use Plan. This limitation on development for environmental reasons has serious consequences for the 120,000 permanent residents within the park boundaries who, through their legislators, vigorously opposed the controls. A number of examples of the conflicts which have arisen are cited and a framework for “comprehensive” rather than “fragmented”planning is suggested. 相似文献
194.
This paper presents an extremely simple proof of the known remarkable fact that for the M/G/1 queue the continuous-time process describing the number of customers in the system has the same limiting distribution as the embedded process describing the number of customers in the system just after service completion epochs. 相似文献
195.
I. H. McNicoll 《Managerial and Decision Economics》1980,1(2):91-98
This paper uses input-output analysis to measure the impact of oil supply bases and oil construction on the economy of Shetland. The output, income and employment created in each local industry by oil activities is measured. Oil industry multipliers are derived. Possible negative effects of oil on the local economy are considered. Finally, a forecast is made of the impact of oil on the Shetland economy in 1985. 相似文献
196.
Dr. H. Vogt 《Metrika》1978,25(1):49-58
Summary If 1, 2,...,
n
and 1, 2,..., –1 are two ordered samples from a population with continuous distribution functionF(x), then the points (
r
,r/n),r=1, 2,..., n–1 provide a better approximation ofF(x) than the points (
r
,r/n),r=1, 2,..., n, in the following sense:A maximal upper deviation and a maximal lower deviation of more theny have — contrary to the points (
r
,r/n) — equal probability for anyy0, if we deal with the points (
r
,r/n). This probability is at least for ally in the interval
, 1 less than the probability for a maximal upper deviation of more thany in the case of the points (
r
,r/n). This is shown by a comparison of the Smirnow-Birnbaum-Tingey — formula with an analogous formula for the maximal one-sided deviations of the points(
r
,r/n). 相似文献
197.
Deborah C. Brown Thomas F. Curry Stephen C. Hoyle John H. Seader John J. Tomick Stephen T. Dziuban 《Socio》1992,26(4):241-255
Counternarcotics interdiction efforts have traditionally relied on historically determined sorting criteria or “best guess” to find and classify suspected smuggling traffic. We present a more quantitative approach which incorporates customized database applications, graphics software and statistical modeling techniques to develop forecasting and classification models. Preliminary results show that statistical methodology can improve interdiction rates and reduce forecast error. The idea of predictive modeling is thus gaining support in the counterdrug community. The problem is divided into sea, air and land forecasting, only part of which will be addressed here. The maritime problem is solved using multiple regression in lieu of multivariate time series. This model predicts illegal boat counts by behavior and geographic region. We developed support software to present the forecasts and to automate the process of performing periodic model updates. During the period, the model was in use at. Coast Guard Headquarters. Because of deterrence provided by improved intervention, the vessel seizure rate declined from 1 every 36 hours to 1 every 6 months. Due in part to the success of the sea model, the maritime movement of marijuana has ceased to be a major threat. The air problem is more complex, and required us to locally design data collection and display software. Intelligence analysts are using a customized relational database application with a map overlay to perform visual pattern recognition of smuggling routes. We are solving the modeling portion of the air problem using multiple regression for regional forecasts of traffic density, and discriminant analysis to develop tactical models that classify “good guys” and “bad guys”. The air models are still under development, but we discuss some modeling considerations and preliminary results. The land problem is even more difficult, and data collection is still in progress. 相似文献
198.
Summary Pseudo Bayesian estimators for the variance components based on Jeffrey’s Rule are derived for the mixed balanced incomplete
block design and are compared with the usual analysis of variance estimators in terms of mean squared error (MSE) efficiency.
Numerical results show that Pseudo-Bayesian estimators are more efficient in numerical results. 相似文献
199.
Corporate mergers possibly enhance the labor negotiation advantage of employers. This study investigates the association between
wage levels and merger activity to test the employer bargaining strength hypothesis. The results indicate significantly lower
union wages as a consequence of merging. Merger activity, however, does not influence wage levels of non-union workers. These
findings are supportive of the employer bargaining strength hypothesis. 相似文献
200.