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101.
《Electrophoresis》2017,38(8):1154-1162
Nonbinary single‐nucleotide polymorphisms (SNPs) are potential forensic genetic markers because their discrimination power is greater than that of normal binary SNPs, and that they can detect highly degraded samples. We previously developed a nonbinary SNP multiplex typing assay. In this study, we selected additional 20 nonbinary SNPs from the NCBI SNP database and verified them through pyrosequencing. These 20 nonbinary SNPs were analyzed using the fluorescent‐labeled SNaPshot multiplex SNP typing method. The allele frequencies and genetic parameters of these 20 nonbinary SNPs were determined among 314 unrelated individuals from Han populations from China. The total power of discrimination was 0.9999999999994, and the cumulative probability of exclusion was 0.9986. Moreover, the result of the combination of this 20 nonbinary SNP assay with the 20 nonbinary SNP assay we previously developed demonstrated that the cumulative probability of exclusion of the 40 nonbinary SNPs was 0.999991 and that no significant linkage disequilibrium was observed in all 40 nonbinary SNPs. Thus, we concluded that this new system consisting of new 20 nonbinary SNPs could provide highly informative polymorphic data which would be further used in forensic application and would serve as a potentially valuable supplement to forensic DNA analysis. 相似文献
102.
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104.
Robert Davis Sarah A. Nelson T. Kyle Petersen Bridget E. Tenner 《Discrete Mathematics》2018,341(11):3249-3270
The peak set of a permutation records the indices of its peaks. These sets have been studied in a variety of contexts, including recent work by Billey, Burdzy, and Sagan, which enumerated permutations with prescribed peak sets. In this article, we look at a natural analogue of the peak set of a permutation, instead recording the values of the peaks. We define the “pinnacle set” of a permutation to be the set . Although peak sets and pinnacle sets mark the same phenomenon for a given permutation, the behaviors of these sets differ in notable ways as distributions over the symmetric group. In the work below, we characterize admissible pinnacle sets and study various enumerative questions related to these objects. 相似文献
105.
对基于直觉模糊信息的多属性决策问题进行了研究,引入了直觉模糊数的得分函数、直觉模糊正理想点和负理想点,然后给出了基于TOPSIS的多属性决策方法,通过计算各备选方案的得分向量与直觉模糊负理想点得分向量之间的距离来确定各备选方案的综合评价指数,进而判断方案的优劣次序.最后,通过一个具体的实例分析说明了该方法的有效性与具体应用过程. 相似文献
106.
Jorge F. Magallanes 《Journal of Chemometrics》2009,23(3):132-138
A new algorithm for sample selection in the field of experimental design is presented. This method was designed for a multivariate data set of samples where the variables' levels are pre‐determined by the system instead of being determined by the practitioner and especially appropriate for non‐symmetrical multivariable space. Symmetrical experimental designs are not applicable in either of the cases. Anyway, this method is also applicable to symmetrical designs. Several tests have been made for symmetrical and non‐symmetrical cases and also about an already treated real case, comparing the new algorithm with others previously known in literature. Its performance has been checked considering several evaluation quality criteria like D‐optimal, A‐optimal, G‐optimal and models error prediction. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
107.
D. B. Abraham 《Journal of statistical physics》1978,19(4):349-358
The critical index values= 7/4 for the susceptibility and=15 for the critical isotherm are derived rigorously for the rectangular Ising ferromagnet with nearest neighbor interactions. The critical indices associated with the Fisher moment definition of the correlation length are obtained asTT
c+. The index of the fluctuation sum definition of critical correlations is obtained.Partially supported by grant PHY 76 17191. 相似文献
108.
Frank Nielsen 《Entropy (Basel, Switzerland)》2021,23(11)
The Jeffreys divergence is a renown arithmetic symmetrization of the oriented Kullback–Leibler divergence broadly used in information sciences. Since the Jeffreys divergence between Gaussian mixture models is not available in closed-form, various techniques with advantages and disadvantages have been proposed in the literature to either estimate, approximate, or lower and upper bound this divergence. In this paper, we propose a simple yet fast heuristic to approximate the Jeffreys divergence between two univariate Gaussian mixtures with arbitrary number of components. Our heuristic relies on converting the mixtures into pairs of dually parameterized probability densities belonging to an exponential-polynomial family. To measure with a closed-form formula the goodness of fit between a Gaussian mixture and an exponential-polynomial density approximating it, we generalize the Hyvärinen divergence to -Hyvärinen divergences. In particular, the 2-Hyvärinen divergence allows us to perform model selection by choosing the order of the exponential-polynomial densities used to approximate the mixtures. We experimentally demonstrate that our heuristic to approximate the Jeffreys divergence between mixtures improves over the computational time of stochastic Monte Carlo estimations by several orders of magnitude while approximating the Jeffreys divergence reasonably well, especially when the mixtures have a very small number of modes. 相似文献
109.
X1,X2,…,Xn是来自总体X的简单随机样本,Nk=min1≤i≤k{Xi},Mk=max1≤i≤k{Xi}(k=1,2,…,n),本文给出了最小次序统计量与最大次序统计量的联合分布函数. 相似文献
110.
This study examined the extreme learning machine (ELM) applied to the Wald test statistic for the model specification of the conditional mean, which we call the WELM testing procedure. The omnibus test statistics available in the literature weakly converge to a Gaussian stochastic process under the null that the model is correct, and this makes their application inconvenient. By contrast, the WELM testing procedure is straightforwardly applicable when detecting model misspecification. We applied the WELM testing procedure to the sequential testing procedure formed by a set of polynomial models and estimate an approximate conditional expectation. We then conducted extensive Monte Carlo experiments to evaluate the performance of the sequential WELM testing procedure and verify that it consistently estimates the most parsimonious conditional mean when the set of polynomial models contains a correctly specified model. Otherwise, it consistently rejects all the models in the set. 相似文献