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11.
We present a number of methods of constructing efficiency-balanced binary block designs which are design patterns for simplification of statistical analysis. Furthermore, a method of construction of an efficiency-balanced block design with v+1 treatments from one with v treatments is generally characterized.  相似文献   
12.
This note presents an extension of Q-method of analysis for binary designs given by Rao (1956) to n-ary balanced and partially balanced block designs. Here a linked n-ary block (LNB) design is defined as the dual of balanced n-ary (BN) design. Having a note on Yates’ (1939, 1940) method of P-analysis, we further extend the expressions for binary linked block (LB) designs given by Rao (1956) to linked n-ary block (LNB) designs which admit easy estimation of parameters for these type of all n-ary designs.  相似文献   
13.
The mean absolute deviation (MAD) estimator has recently received a great deal of attention as applied to full-rank linear regression models. This paper provides a necessary and sufficient condition for the MAD estimator to be a non-linear estimator, in which case conditions for the variance of the MAD estimator to be larger or smaller than those for OLS are, in general, unknown. The non-linearity of the MAD estimator is examined for several two-way designs; in particular (1) randomized block design (2) two-way nested design (3) two-way classification with interaction and (4) partially balanced incomplete block design  相似文献   
14.
This deals with chemical balance weighing designs which attain a lower bound for the variance of the estimated total weight, The results extend those of Chacko Dey (1978).  相似文献   
15.
ABSTRACT

In this article we investigate the design of scoring schemes for surveys using the block total response method. This method was first proposed by Raghavarao and Federer (1979 Raghavarao , D. , Federer , W. T. ( 1979 ). Block total response as an alternative to the randomized response method in surveys . J. Roy. Statist. Soc. 41 ( 1 ): 4045 . [CSA] [CROSSREF]  [Google Scholar]) to provide accurate estimates of the base rates of sensitive characteristics using balanced incomplete block designs. The scoring scheme used in Raghavarao and Federer (1979 Raghavarao , D. , Federer , W. T. ( 1979 ). Block total response as an alternative to the randomized response method in surveys . J. Roy. Statist. Soc. 41 ( 1 ): 4045 . [CSA] [CROSSREF]  [Google Scholar]) did not guarantee anonymity of answers and so the possibility of improving on this basic scoring scheme is considered in this article.  相似文献   
16.
In this paper, Yate's missing plot technique is used to derive the formula for substitution in a missing plot in a general incomplete block design, where blocks are assumed to be independent normal. The use of penalized normal equations, using BLUPS, makes this task simpler.  相似文献   
17.
We present a class of counerexamples for a conjecture on the existence or linear trend free block designs we will also prove a considerably weakened version of this conjecture which will determine all combinations of designs parmetres for which the class of linear trend free block designs is non empty.  相似文献   
18.
Fault diagnosis includes the main task of classification. Bayesian networks (BNs) present several advantages in the classification task, and previous works have suggested their use as classifiers. Because a classifier is often only one part of a larger decision process, this article proposes, for industrial process diagnosis, the use of a Bayesian method called dynamic Markov blanket classifier that has as its main goal the induction of accurate Bayesian classifiers having dependable probability estimates and revealing actual relationships among the most relevant variables. In addition, a new method, named variable ordering multiple offspring sampling capable of inducing a BN to be used as a classifier, is presented. The performance of these methods is assessed on the data of a benchmark problem known as the Tennessee Eastman process. The obtained results are compared with naive Bayes and tree augmented network classifiers, and confirm that both proposed algorithms can provide good classification accuracies as well as knowledge about relevant variables.  相似文献   
19.
针对大庆外围油田特低渗透油藏剩余油潜力大、井网加密效益差、水驱采收率低等问题,提出了特低渗透油藏 CO2驱技术。通过细管实验和天然岩芯 CO2 驱油实验,确定了 CO2 与高台子油田原油的最小混相压力,评价了特低渗透砂岩油藏 CO2 驱油效果。实验结果表明,CO2 驱可以应用于高台子油田,并取得较好的驱油效果。当天然岩芯空气渗透率为0.58 mD 时,在水驱基础上,气驱可以进一步提高采收率 8% 以上,特低渗透油藏实施 CO2 驱油技术是可行的。  相似文献   
20.
华庆地区长6深水沉积低渗透砂岩储层特征   总被引:1,自引:0,他引:1  
通过大量岩芯、铸体薄片、扫面电镜及物性资料分析,对鄂尔多斯盆地华庆地区长6段砂岩的沉积特征、岩石学特征、孔渗特征、成岩作用类型、孔隙结构及孔隙类型等进行了深入研究。研究表明,以深水浊积砂体为主的长6储层具有沉积物粒度偏细、成分成熟度较低、结构成熟度中等的岩石学特点;储集空间主要是原生粒间孔隙和次生溶蚀孔隙,孔隙结构以中、小孔细喉型为主。研究区孔隙度与渗透率具有较好的正相关性,为一套典型的低孔、低渗到特低孔、特低渗的储层。  相似文献   
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