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31.
在实现马克思主义中国化第二次历史飞跃的过程中,无论是历史和逻辑的起点,还是历史的逻辑和逻辑的历史,都昭示了邓小平理论作为马克思主义中国化第二次飞跃的理论成果,其形成和发展是一个复杂的逻辑与历史、理论与实践、主观与客观矛盾统一的过程。具体考察这一过程中理论逻辑和历史逻辑的内在关系及其相互转化的机制,探讨邓小平理论逻辑的风格和个性特点,有利于我们更深刻地认识和把握马克思主义中国化第二次飞跃过程的一般规律。  相似文献   
32.
Generalized additive models for location, scale and shape   总被引:10,自引:0,他引:10  
Summary.  A general class of statistical models for a univariate response variable is presented which we call the generalized additive model for location, scale and shape (GAMLSS). The model assumes independent observations of the response variable y given the parameters, the explanatory variables and the values of the random effects. The distribution for the response variable in the GAMLSS can be selected from a very general family of distributions including highly skew or kurtotic continuous and discrete distributions. The systematic part of the model is expanded to allow modelling not only of the mean (or location) but also of the other parameters of the distribution of y , as parametric and/or additive nonparametric (smooth) functions of explanatory variables and/or random-effects terms. Maximum (penalized) likelihood estimation is used to fit the (non)parametric models. A Newton–Raphson or Fisher scoring algorithm is used to maximize the (penalized) likelihood. The additive terms in the model are fitted by using a backfitting algorithm. Censored data are easily incorporated into the framework. Five data sets from different fields of application are analysed to emphasize the generality of the GAMLSS class of models.  相似文献   
33.
Summary.  We consider a Bayesian forecasting system to predict the dispersal of contamination on a large scale grid in the event of an accidental release of radioactivity. The statistical model is built on a physical model for atmospheric dispersion and transport called MATCH. Our spatiotemporal model is a dynamic linear model where the state parameters are the (essentially, deterministic) predictions of MATCH; the distributions of these are updated sequentially in the light of monitoring data. One of the distinguishing features of the model is that the number of these parameters is very large (typically several hundreds of thousands) and we discuss practical issues arising in its implementation as a realtime model. Our procedures have been checked against a variational approach which is used widely in the atmospheric sciences. The results of the model are applied to test data from a tracer experiment.  相似文献   
34.
Summary.  The pattern of absenteeism in the downsizing process of companies is a topic in focus in economics and social science. A general question is whether employees who are frequently absent are more likely to be selected to be laid off or in contrast whether employees to be dismissed are more likely to be absent for the remaining time of their working contract. We pursue an empirical and microeconomic investigation of these theses. We analyse longitudinal data that were collected in a German company over several years. We fit a semiparametric transition model based on a mixture Poisson distribution for the days of absenteeism per month. Prediction intervals are considered and the primary focus is on the period of downsizing. The data reveal clear evidence for the hypothesis that employees who are to be laid off are more frequently absent before leaving the company. Interestingly, though, no clear evidence is seen that employees being selected to leave the company are those with a bad absenteeism profile.  相似文献   
35.
设s,t满足gcd(s,t)=1,s>t的正整数,a=2st,b=s~2-t~2,c=s~2+t~2。证明了:若c为素数幂且满足下列条件之一:(1)b有因子b_1≡±5(mod8),(2)b≡-1(mod8),(3)5|c。则不定方程x~2+b~y=c~z仅有一组正整数解(x,y,z)=a,2,2。  相似文献   
36.
讨论了非线性时滞微分方程H(t,x(t),x(t—r)+f(t,x(t—τ))—g(x(t—σ))=0的振动性,推广了有关文献的部分结果.  相似文献   
37.
本文分析了考试记分方法中传统的绝对百分体制的缺陷,给出了一种正态化转换分数的算法,较适合于在校大中专学生学习水平的横向评价。  相似文献   
38.
发展了Baksalary和Drygas提出的一般Gauss-Markov模型中线性充分性、最小充分性和完全性的概念,用Rao的最小二乘统一理论,给出了这些概念的刻划定理。  相似文献   
39.
从微分方程的角度出发 ,分三个方面讨论了一类收敛级数求和问题的具体解法。  相似文献   
40.
Summary.  We define residuals for point process models fitted to spatial point pattern data, and we propose diagnostic plots based on them. The residuals apply to any point process model that has a conditional intensity; the model may exhibit spatial heterogeneity, interpoint interaction and dependence on spatial covariates. Some existing ad hoc methods for model checking (quadrat counts, scan statistic, kernel smoothed intensity and Berman's diagnostic) are recovered as special cases. Diagnostic tools are developed systematically, by using an analogy between our spatial residuals and the usual residuals for (non-spatial) generalized linear models. The conditional intensity λ plays the role of the mean response. This makes it possible to adapt existing knowledge about model validation for generalized linear models to the spatial point process context, giving recommendations for diagnostic plots. A plot of smoothed residuals against spatial location, or against a spatial covariate, is effective in diagnosing spatial trend or co-variate effects. Q – Q -plots of the residuals are effective in diagnosing interpoint interaction.  相似文献   
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