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891.
892.
Poduri S.R.S. Rao 《统计学通讯:理论与方法》2013,42(15):1659-1669
The MINQUE and its modifications are considered for estimating the variances of the balanced one-way random effects model. The effects of the a priori values on the estimators of the variances are examined in detail. The Mean Square Errors of the estimators are compared for variations in the prior values of the unknown variances. 相似文献
893.
Abstract We specify a revised model of the demographic transition which accounts for national fertility levels and changes over the past two decades. The model includes cultural, geographic, demographic and family planning program variables, in addition to a measure of national socio-economic modernization. Using crude birth rates for 117 countries, we operationalize and then apply the revised model to 1974 rates, and then test a longitudinal model of 1955–59 to 1974 change in rates. A final model for 81 less developed nations from the original set of 117 countries includes a measure of family planning program effort. Including this highly significant measure in a model of 1955–59 to 1974 change results in further evidence favoring modification of the traditional demographic transition model. Implications for the future course of fertility in underdeveloped countries are discussed. 相似文献
894.
Final assembly plants send material schedules to first-tier suppliers who in turn send schedules to second-tier suppliers and so on through the multiple tiers of the supply chain. A key cost driver for the supply chain is a schedule characteristic termed stability. The Total Quality Management approach is applied to improve schedule stability in the supply chain of a large vertically integrated automotive manufacturer. A measurement described, actual stability results are provided, the causes of instability are listed, and some corrective actions are specified. Results indicate that schedule stability can be improved without damaging the performance of other measures such as inventory and customer responsiveness. and analysis process is 相似文献
895.
In this paper, we link production planning decisions to marketing decisions that involve the price of product groups. The focus of this paper is the development of a closed-loop procedure for aggregate production planning and pricing. We seek to satisfy uncertain demand while minimizing total costs that include material, labour, and inventory holding costs. The procedure is useful for variable demand to update short-term aggregate plans. 相似文献
896.
In this paper the robustness of Brass's child-survivorship indirect mortality estimation technique is investigated. An analytical method is developed for studying the error or bias caused in indirect mortality estimates by poor data, badly chosen model functions, and specific demographic assumptions that are often violated in practice. The resulting analytical expressions give insight into the rationale of indirect methods, the conditions under which they are robust, and the magnitude of errors that occur when specific assumptions are violated. 相似文献
897.
Some degree of error is inevitable in multi‐agent bioassays regardless of design or measurement technology. Estimation error can be reduced post facto by exploiting the matrix partial ordering of the bioassay survival estimates. The standard method for this is order‐restricted regression (ORR). If the joint action of the bioassay agents admits a tolerance‐based interpretation, additional structure beyond matrix partial ordering is available, leading to a new method of error reduction. This tolerance‐based error reduction (TBER) procedure almost always outperforms ORR. Like ORR, TBER applies to complete factorial bioassay designs and, using weighting, to incomplete designs. 相似文献
898.
Despite the prevalence of goal setting in organizations, researchers have not thoroughly examined the implications of goal setting to work outcomes in interdependent work settings. A field survey (n= 442) assessed the relation of goal setting and goal sharing, the extent to which others are aware of an individual's work goal, to performance and conflict across varying levels of task interdependence. The results of moderated regression analyses demonstrate that in highly interdependent tasks, the use of goal setting resulted in lower performance levels. Moreover, goal setting and goal sharing in highly interdependent tasks resulted in individuals' reporting more somatic symptoms. The results are discussed in terms of clarifying the role of goal setting for interdependent tasks. 相似文献
899.
Network Evening News Coverage of Environmental Risk 总被引:2,自引:0,他引:2
Michael R. Greenberg David B. Sachsman Peter M. Sandman Kandice L. Salomone 《Risk analysis》1989,9(1):119-126
ABC, CBS, and NBC's carefully crafted and expensively produced evening news broadcasts devoted 1.7% of their air time to 564 stories about man-made environmental risks during the period from January 1984 to February 1986. Little relationship was found between amount of coverage and public health risk. Instead, the networks appeared to be using traditional journalistic determinants of news (timeliness, proximity, prominence, consequence, and human interest) plus the broadcast criterion of visual impact to determine the degree of coverage of risk issues. Government, industry, and citizens accounted for two-thirds of the sources cited by the networks. Experts and spokespersons for environmental advocacy groups were sparsely used as sources. Given the media's need for news pegs, acute and chronic risk stories were covered differently. Acute risk stories were reported in a clearly defined cycle, peaking on the second day with on-the-scene reports and film-clips of devastation. In keeping with a decrease in visual drama, later reports were shorter and emphasized legal and political considerations. Chronic risk coverage followed the release of new scientific, legal, or political information. 相似文献
900.
A class of decisions, asset mix decisions made by pension fund managers, which exhibit characteristics of both programmed and strategic choices is examined in this paper. The decisions are classified using the scheme developed by Mintzberg et al., (1976) to highlight the circumstances under which strategic decisions may be programmed. The types of strategic decisions which lend themselves to programming are considered. The advantages and disadvantages of programming strategic decisions are also discussed. 相似文献