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81.
通过介绍楼面基准地价系数修正法的具体应用,探讨商住综合用地的地价评估思路。在阐述楼面地价及楼面基准地价评估方法的基础上,结合长沙市楼面基准地价水平,采用实证分析方法与对比分析方法,提出楼面基准地价系数修正法在商住综合用地地价评估中的具体应用过程,并与现行商住综合用地的评估方法(分算法)进行对比分析。指出楼面基准地价系数修正法较分算法评估商住综合用地地价,能更真实地体现立体地价水平,更具合理性。  相似文献   
82.
课程教学模式的改革与创新是教学改革的核心,是进一步提高应用型本科教学质量的关键。而当前《工程估价》课程教学中存在很多问题,如教师素质的培养、学生兴趣的激发、教学方法的改革等。通过《工程估价》课程教学改革,可进一步提高该课程的教学效果,并达到以点带面的目的,为培养合格的应用型人才奠定基础。  相似文献   
83.
In this note, we focus on estimating the false discovery rate (FDR) of a multiple testing method with a common, non-random rejection threshold under a mixture model. We develop a new class of estimates of the FDR and prove that it is less conservatively biased than what is traditionally used. Numerical evidence is presented to show that the mean squared error (MSE) is also often smaller for the present class of estimates, especially in small-scale multiple testings. A similar class of estimates of the positive false discovery rate (pFDR) less conservatively biased than what is usually used is then proposed. When modified using our estimate of the pFDR and applied to a gene-expression data, Storey's q-value method identifies a few more significant genes than his original q-value method at certain thresholds. The BH like method developed by thresholding our estimate of the FDR is shown to control the FDR in situations where the p  -values have the same dependence structure as required by the BH method and, for lack of information about the proportion π0π0 of true null hypotheses, it is reasonable to assume that π0π0 is uniformly distributed over (0,1).  相似文献   
84.
In this paper, we discuss a parsimonious approach to estimation of high-dimensional covariance matrices via the modified Cholesky decomposition with lasso. Two different methods are proposed. They are the equi-angular and equi-sparse methods. We use simulation to compare the performance of the proposed methods with others available in the literature, including the sample covariance matrix, the banding method, and the L1-penalized normal loglikelihood method. We then apply the proposed methods to a portfolio selection problem using 80 series of daily stock returns. To facilitate the use of lasso in high-dimensional time series analysis, we develop the dynamic weighted lasso (DWL) algorithm that extends the LARS-lasso algorithm. In particular, the proposed algorithm can efficiently update the lasso solution as new data become available. It can also add or remove explanatory variables. The entire solution path of the L1-penalized normal loglikelihood method is also constructed.  相似文献   
85.
当前我国的基本建设和建筑业的预算超概算 .概算超估算的现象十分严重 ,要避免这一现象的发生 ,必须加强设计控制  相似文献   
86.
In the analysis of retrospective data or when interpreting results from a single-arm phase II clinical trial relative to historical data, it is often of interest to show plots summarizing time-to-event outcomes comparing treatment groups. If the groups being compared are imbalanced with respect to factors known to influence outcome, these plots can be misleading and seemingly incompatible with results obtained from a regression model that accounts for these imbalances. We consider ways in which covariate information can be used to obtain adjusted curves for time-to-event outcomes. We first review a common model-based method and then suggest another model-based approach that is not as reliant on model assumptions. Finally, an approach that is partially model free is suggested. Each method is applied to an example from hematopoietic cell transplantation.  相似文献   
87.
《南都学坛》2000,20(3):1-6
对包含测度的椭圆方程 ,证明解的有界性已颇为困难 ,对解的最大模作出估计尤其困难。本文只对其中一种特殊情形作出解最大模的先验估计。  相似文献   
88.
The conditional mixture likelihood method using the absolute difference of the trait values of a sib pair to estimate genetic parameters underlies commonly used method in linkage analysis. Here, the statistical properties of the model are examined. The marginal model with a pseudo-likelihood function based on a sample of the absolute difference of sib-traits is also studied. Both approaches are compared numerically. When genotyping is much more expensive than screening a quantitative trait, it is known that extremely discordant sib pairs provide more powerful linkage tests than randomly sampled sib pairs. The Fisher information about genetic parameters contained in extremely discordant sib pairs is calculated using the marginal mixture model. Our results supplement current research showing that extremely discordant sib pairs are powerful for the linkage detection by demonstrating they also contain more information about other genetic parameters.  相似文献   
89.
A Bayesian nonparametric estimate of the survival distribution is derived under a particular sampling scheme for grouped data that includes the possibility of censoring. The estimate uses the prior information to smooth the data, giving an estimate which is continuous. As special cases survival estimates for life tables are obtained and the estimate of Susarla and Van Ryzin (1976) is derived. As the weight of the prior information tends to zero, the Bayesian estimate reduces to a continuous version of the nonparametric maximum-likelihood estimate. An empirical Bayes modification of the procedure is illustrated on a data set from Cutler and Ederer (1958).  相似文献   
90.
本文在文献[1]的基础上给出了更为一般的探讨,并且用主成分估计法改进了灰色系统模型。  相似文献   
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