分布函数间几种散布序的关系

设 F是分布函数 ,对 α∈ (0 ,1 ) ,记 X+F (α) =sup{ x:F(x) <α} ,X-F (α) =inf{ x:F(x) >α} ,XF(α) =(X+F (α) +X-F (α) ) /2 .本文给出了分布函数 F和 G之间的一种散布序 ,记作 d≤ ,F d≤ G 0 <α<β<1 ,XF(β) - XF(α)≤ XG(β) - XG(α) .在一定的条件下 ,讨论了几种散布序 d≤ ,disp≤ ,d*≤ 的等价关系     

水稻纹枯病流行程度的模型预测

根据水稻纹枯病发生与危害程度的调查资料,经与各诱病因素的相关性分析,组建成早、晚稻纹枯病的长期预测模型。经1990～1994年的应用检验,预测准确率达80％以上。     

竖炉散料层热交换公式的简化计算及应用讨论

在竖炉内散料层的逆流换热系统中存在这样一个炉气与炉料温度实际相等的区域，据炉气与炉料水当量的变化特征，本文在Ｂ．Ｈ基塔耶夫建立的逆流换热模型公式的基础上、整理出更为简单，清晰的竖炉散料层热交换的简化计算式，并进行了应用讨论。     

The role of macroeconometric models in forecasting and policy analysis in the united states

This article stresses how little is known about the quality, particularly the relative quality, of macroeconometric models. Most economists make a strict distinction between the quality of a model per se and the accuracy of solutions based on that model. While this distinction is valid, it leaves unanswered how to compare the‘validity’of conditional models. The standard test, the accuracy of ex post simulations, is not definitive when models with differing degrees of exogeneity are compared. In addition, it is extremely difficult to estimate the relative quantitative importance of conceptual problems of models, such as parameter instability across‘policy regimes’ In light of the difficulty in comparisons of conditional macroeconometric models, many model-builders and users assume that the best models are those that have been used to make the most accurate forecasts are those made with the best models. Forecasting experience indicates that forecasters using macroeconometric models have produced more accurate macroeconomic forecasts than either naive or sophisticated unconditional statistical models. It also suggests that judgementally adjusted forecasts have been more accurate than model-based forecasts generated mechanically. The influence of econometrically-based forecasts is now so pervasive that it is difficult to find examples of‘purely judgemental’forecasts.     

Nonlinearity degree of short-term heart rate variability signal

A nonlinear autoregressive (NAR) model is built to model the heartbeat interval time series and the optimum model degree is proposed to be taken to evaluate the nonlinearity degree of heart rate variability (HRV). A group of healthy persons are studied and the results indicate that this method can effectively get nonlinear information from short (6—7 min) heartbeat series and consequently reflect the degree of heart rate variability, which supplies convenience in clinical application. Finally, a comparison with the traditional time domain method shows that the NAR model method can reflect the complexity of the whole signal and lessen the influence of noise and instability, in the signal.     

论"顾客满意战略"在图书馆工作中的应用

最大限度地满足读者,已成为现代图书馆服务理念的核心.图书馆应导入顾客满意战略,努力营造顾客满意战略实施的环境,加强读者信息管理,以读者需求引导图书馆服务创新,开展导向型服务,并进行读者满意度测评,进一步完善顾客满意战略的实施.     

"奖优罚劣"的动态多指标灰色关联度模型研究

针对动态多指标系统决策特点 ,利用灰色关联分析方法提出了一种新的“奖优罚劣”的动态多指标决策模型。该模型不仅对指标进行初始化处理时使用了“奖优罚劣”原则 ,而且通过构造相关矩阵 ,利用特征根、特征向量的性质 ,构造最优指标体系 ,并由此确定最优指标体系中各指标的权重。通过计算决策对象与理想矩阵、负理想矩阵的关联度 ,进而得到决策对象的排序结果。模型中充分考虑了指标的成长特性 ,将其整个系统的成长特性进行比较 ,作为关联度的一部分。在经济决策的实际问题中应用该模型 ,取得较好的效果     

广告的效果构成与广告创意及其实施与控制

广告效果由广告的刺激强度、广告价值笼络力和广告购买决策驱动力三个层面构成,沿着这三个方向进行广告创意并进行有效的实施与控制,是保证广告效果的必然途径。其中,把握好广告背景和心理“差补效应”对实现广告创意及其实施与控制的有效性尤为重要。     

顾客满意度的模糊DEA评价

将模糊理论与DEA方法相结合评价顾客满意度,顾客只需作出自己的模糊印象结论,而每个决策单元的“输入”和“输出”的权重由其实际数据求得。     

不同层次模糊信息的加权综合方法

在模糊控制与模糊规划等许多实际问题中,常常需要针对某种运算规则求模糊数在不同水平下的综合截集,该文在分析了这种运算的内在机理的基础上,采用水平加权的方法,给出了确定模糊数的在不同截集水平下的综合截集的规则,并从水平截集的对称差集合的Lebesgue测度出发,引入了模糊数关于水平的清晰程度概念,进而建立了一种客观地综合不同截集水平的方法,给出了三角模糊数关于不同层次水平的运算公式。这些讨论将为不同层次信息的综合以及不同层次水平的模糊规划和模糊优化问题提供一种有效的途径。