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1.
肩胛骨性别的判别分析 总被引:1,自引:0,他引:1
就青岛出土已知性别成年肩胛骨84例(男66,女18)进行了12项测量,从中挑选出肩胛形态宽(X1),肩胛宽(X2),肩胛冈长(X3)和关节盂长(X4)四个变量,按Fisher法进行判别分析,其中有五种组合方式其判别率均在92.9%以上,而X3与X4两因素判别率最优,高达97.62%。此法简便,准确,具有较高的实用价值。 相似文献
2.
太行山猕猴肩胛骨和肱骨性差的研究 总被引:1,自引:0,他引:1
以26例成年太行山猕猴肩胛骨和肱骨的15项线性变量为对象,运用SPSS 12.0统计分析软件对其进行双变量相关分析、异速生长分析和主成分分析,以探讨各变量之间的性差大小以及产生的原因.结果表明,太行山猕猴雌雄之间存在明显的性差.其原因可能与性成熟时间、生长速率的不同以及各自的生活方式和运动行为有关. 相似文献
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《菌物学报》2017,(1):112-125
利用近红外光谱鉴别云南不同产区药用真菌茯苓。采用光谱标准偏差法(SSD)和蒙特卡罗无信息变量消除法(MC-UVE)逐步筛选光谱信息,利用K-S算法将白茯苓和茯苓皮划分训练集和验证集,并结合偏最小二乘判别分析法(PLS-DA)分别构建不同产区白茯苓和茯苓皮的分类模型,进一步建立不同产区茯苓的Fisher判别方程。结果表明:(1)通过主成分-马氏距离(PCA-MD)分析,白茯苓和茯苓皮的近红外光谱在主成分得分空间内呈现出较大差异,构建不同产区茯苓鉴别模型应将白茯苓及茯苓皮分开。(2)最优主成分数为5时,采用SSD筛选的886个变量(7 501.74–4 088.35cm~(-1))构建的白茯苓和茯苓皮的分类模型,其R~2、RMSECV和RMSEP分别为0.986、0.988;0.320、0.283;0.425、0.395;采用MC-UVE法分别筛选出白茯苓和茯苓皮光谱信息(34个、22个变量)建立的分类模型,其R~2、RMSECV和RMSEP分别为0.993、0.991;0.224、0.255;0.298、0.355。采用MC-UVE结合PLS-DA法建立的分类模型,有效降低了冗余信息,白茯苓和茯苓皮的R~2均有所提升,RMSECV和RMSEP均有所降低,预测正确率分别由85.71%和83.33%,提高至100%。(3)进一步采用逐步判别分析法筛选出白茯苓(6个)和茯苓皮(4个)光谱变量,建立Fisher判别方程,回代验证正确率均大于85.7%,交叉验证正确率均大于66.7%,表明所建立的Fisher判别方程能较好地鉴别不同产区的茯苓。 相似文献
4.
太行山猕猴掌骨性别判别分析 总被引:4,自引:0,他引:4
为了了解成年太行山猕猴5根掌骨的性差大小。本文对太行山猕猴掌骨标本40例(雄:10, 雌:30)进行观察并选择掌骨的9项形态变量进行测量。数据用SPSS19.0软件进行多变量判别分析。结果表明: 5根掌骨长度等变量在性别之间有明显差异。用全模型法5根掌骨的性别正确判别率范围为94.1%~100.0%, 用逐步判别法掌骨性别正确判别率范围为93.8%~97.5%。有关掌骨的9个形态变量, 长度变量首先被挑选出来, 说明在性别判别中起重要作用。分别用左右侧掌骨的判别函数来判别性别时侧别差异不明显。结论: 用每根掌骨的形态变量建立判别函数可以有效地区分性别, 对非人灵长类掌骨标本的性别鉴定有一定的理论意义和应用价值。 相似文献
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6.
美国紫踵劈蚌与三角帆蚌和褶纹冠蚌的形态比较与判别分析 总被引:5,自引:0,他引:5
描述了紫踵劈蚌(Potamilus alatus)贝壳外部和内部特征,并对紫踵劈蚌、三角帆蚌(Hyriopsis cumingii)和褶纹冠蚌(Cristaria plicata)进行了形态学比较。运用多变量形态度量学方法分析了3种淡水育珠蚌的形态差异。主成分分析构建了2个主成分,其中第一主成分的方差贡献率为66·90%,第二主成分的贡献率为33·10%,2个主成分的累计贡献率达到100%;采用逐步判别法,从11个比例性状中筛选出6个主要性状建立了3种育珠蚌的形态判别函数,其综合判别准确率达到100%。 相似文献
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太行山猕猴下颌骨变量相关性研究 总被引:10,自引:2,他引:8
本研究测量了18例(雄4,雌14)成年太行山猕猴下颌骨的12项变量。通过对下颌骨变量的性别判别分析和相关分析。结果显示:太行山猕猴下颌骨变量有其自身特征,与其它猕猴下颌骨资料比较表现出一定差异;用Ottestat方法对有关变量建立性别判别函数式,其判别率达86.86%,下颌骨变量相关性研究表明,各变量之间有正相关,也有负相关,大多数变量之间相互程度较差,不同变量之间其相关程度存在一定差异。 相似文献
9.
太行山猕猴掌骨和踽骨长度的性别判别 总被引:1,自引:0,他引:1
研究太行山猕猴掌骨和蹠骨长度的性别差异.对24例掌骨和26例蹠骨的长度变量进行测量,用SPSS13.0统计软件进行单因素方差分析和多变量判别分析.结果表明:掌骨和踱骨的长度变量在性别之间有极显著性差异(P<0.00).各掌骨和各踱骨的长度顺序在侧别之间和性别之间有一定差异,但是尚未达到统计学意义(P>0.05).用全模型法和逐步判别法根据长度变量分别建立性别判别函数,其性别正确判别率掌骨分别为91.7%和93.8%,而蹠骨的性别判别率为84.6%.表明猕猴掌骨和蹠骨长度性别之间存在明显性差.使用掌骨和踱骨长度变量进行性别鉴定有一定理论价值和应用价值. 相似文献
10.
太行山猕猴掌骨和蹠骨长度的性别判别 总被引:3,自引:0,他引:3
研究太行山猕猴掌骨和蹠骨长度的性别差异。对24例掌骨和26例蹠骨的长度变量进行测量, 用SPSS13.0统计软件进行单因素方差分析和多变量判别分析。结果表明: 掌骨和蹠骨的长度变量在性别之间有极显著性差异(P<0.00)。各掌骨和各骨的长度顺序在侧别之间和性别之间有一定差异, 但是尚未达到统计学意义( P> 0.05) 。用全模型法和逐步判别法根据长度变量分别建立性别判别函数, 其性别正确判别率掌骨分别为91.7%和93.8%, 而蹠骨的性别判别率为84.6%。表明猕猴掌骨和蹠骨长度性别之间存在明显性差。使用掌骨和蹠骨长度变量进行性别鉴定有一定理论价值和应用价值。 相似文献
11.
影响水稻光合日变化的酶和相关因素的分析 总被引:13,自引:0,他引:13
水稻叶片的最大光合速率出现在上午10:00时,Rubisco初始活力也在此时达到最大,然后逐渐降低,下午14:00时略上升后又下降.Rubisco初始活力与光合速率之间极显著相关,相关系数为 0.9474.运用相关性分析、回归分析、通径分析,对晴(有时有云)天气水稻叶片的光合速度、光合关键酶及有关因素的日变化进行综合评估,结果发现中午光合下降主要来自气孔限制,同时Rubisco活性也下降;Rubisco活性是影响光合日变化的又一重要生化因子.体内Rubisco活性受Rubisco活化酶的调节. 相似文献
12.
甲醇对酵母过氧化氢酶活性的影响机理研究 总被引:5,自引:0,他引:5
将酵母过氧化氢酶加入一定比例的甲醇,测定其活性变化。结果表明:在含2%甲醇时酶活比对照提高4026%。将粗酶液用70%饱和度的硫酸铵盐析后离心所得的上清液再加入硫酸铵至80%饱和度,离心的沉淀溶解在缓冲液中,上SephadexG75柱,分离出的有酶活性的蛋白峰经电泳得一条蛋白带,说明过氧化氢酶已经被提纯到电泳纯。光谱分析发现,甲醇处理后过氧化氢酶纯酶的吸收光谱和荧光发射光谱与未经处理的比较基本不变,而差示光谱出现明显的正峰和负峰。由动力学分析可知,在甲醇中,过氧化氢酶的Vmax和Km值均有不同程度提高 。 相似文献
13.
Goodness of fit of biplots and correspondence analysis 总被引:3,自引:0,他引:3
14.
凡纳滨对虾各月龄性状的主成分与判别分析 总被引:8,自引:0,他引:8
为了研究凡纳滨对虾各性状增长规律和判定最佳生长季节凡纳滨对虾的体格与月龄的关系,选择1~6月龄凡纳滨对虾各1000只,选择全长、体长、第一腹节背高、第三腹节背高、第一腹节背宽、头胸甲长和体重共7个性状,进行主成分与判别分析.结果表明:各月龄凡纳滨对虾性状之间均呈现显著的正相关(P<0.01), 其中以全长与体长的相关性最为明显,1月龄凡纳滨对虾体重与形态性状的相关系数较小.各月龄凡纳滨对虾的主成分有所不同,1~2月龄凡纳滨对虾的第一主成分为长度因子,第二主成分为宽度因子,第三主成分为高度因子;3月龄凡纳滨对虾的第一主成分与1~2月龄凡纳滨对虾一致,但第二主成分为高度因子,第三主成分为体重因子;4~6月龄凡纳滨对虾的第一主成分为体重因子,第二主成分为高度因子,第三主成分为宽度因子.1~3月龄凡纳滨对虾形态性状的增长优先于体重, 4~6月龄凡纳滨对虾体重优先于形态性状的增长.错过最佳生长季节的凡纳滨对虾的与体格大小相符的月龄可通过建立的判别式来判断,总的判别准确率为98.98%,其中2~4月龄凡纳滨对虾的判别准确率为100%. 相似文献
15.
Lawrence J 《Biometrical journal. Biometrische Zeitschrift》2005,47(5):616-622
In an active-controlled trial, the experimental treatment can be declared to be non-inferior to the control if the confidence interval for the difference excludes a fixed pre-specified margin. Recently, some articles have discussed an alternative method where the data from the current study and placebo-controlled studies for the active control are combined together into a single test statistic to test whether a fixed fraction of the effect of the active control is preserved. It has been shown that, conditional on nuisance parameters from the active-controlled study, a fixed margin can be defined that will be operationally equivalent to this latter method. In this article, we will discuss statistical properties associated with these approaches. Specifically, the interim monitoring boundaries and level of evidence will be considered. 相似文献
16.
Pyrolysis mass spectrometry (PyMS) is a rapid, simple, high-resolution analytical method based on thermal degradation of complex
material in a vacuum, and has been widely applied to the discrimination of closely related microbial strains. Minimally prepared
samples of embryogenic and non-embryogenic calluses derived from various higher plants (sweet potato, morning glory, Korean
ginseng, Siberian ginseng, and balloon flower) were subjected to PyMS for spectral fingerprinting. A dendrogram based on the
unweighted pair group method, with arithmetic mean of pyrolysis mass spectra, divided the calluses into Siberian ginseng embryogenic
callus and the others, which were subsequently divided into embryogenic and non-embryogenic callus groups, regardless of plant
species from which the calluses were derived. In the non-embryogenic callus group, the dendrogram was in agreement with the
known taxonomy of the plants. These results indicate that PyMS analysis could be applied for discriminating plant calluses
based on embryogenic capacity and taxonomic classification. 相似文献
17.
Ashutosh Kushwah Dharminder Bhatia Gurpreet Singh Inderjit Singh Shayla Bindra Suruchi Vij Sarvjeet Singh 《Physiology and Molecular Biology of Plants》2021,27(4):747
Heat is a major abiotic stress that drastically reduces chickpea yield. This study aimed to identify heat-responsive traits to sustain crop productivity by screening a recombinant inbred line (RILs) population at two locations in India (Ludhiana and Faridkot). The RIL population was derived from an inter-specific cross between heat-tolerant genotype GPF 2 (C. arietinum L.) and heat sensitive accession ILWC 292 (C. reticulatum). The pooled analysis of variance showed highly significant differences for all the traits in RILs and most of the traits were significantly affected by heat stress at both locations. High values of genotypic coefficient of variation (19.52–38.53%), phenotypic coefficient of variation (20.29–39.85%), heritability (92.50–93.90%), and genetic advance as a percentage of mean (38.68–76.74%) have been observed for plant height, number of pods per plant, biomass, yield, and hundred seed weight across the heat stress environments. Association studies and principal component analysis showed a significant positive correlation of plant height, number of pods per plant, biomass, hundred seed weight, harvest index, relative leaf water content, and pollen viability with yield under both timely-sown and late-sown conditions. Path analysis revealed that biomass followed by harvest index was the major contributor to yield among the environments. Both step-wise and multiple regression analyses concluded that number of pods per plant, biomass and harvest index consistently showed high level of contribution to the total variation in yield under both timely-sown and late-sown conditions. Thus, the holistic approach of these analyses illustrated that the promising traits provide a framework for developing heat-tolerant cultivars in chickpea.Supplementary InformationThe online version contains supplementary material available at 10.1007/s12298-021-00977-5. 相似文献
18.
The most common tests for types and antitypes in configural frequency analysis are normal approximations of exact tests. In the paper such statistics under the complete independence model and under the fixed margins model are discussed. It turns out that these test statistics are not acceptable when the number of simultaneously performed tests is large or when the expected frequencies are small. In these cases, the use of exact tests is advocated and some existing computer programs for such tests are indicated. A normal approximation based on the strong version of the De Moivre-Laplace limit theorem is also discussed. Empirical examples are given from longitudinal data describing psychological development of boys. 相似文献
19.
The aim of this study was to compare the densification of powder mixtures on eccentric and rotary tablet presses and to establish
relationships with the halving properties of the resulting scored tablets. This is an important problem because the recent
guidelines of EU require verification of the equal masses of tablet halves. The models of Walker, Heckel, and Kawakita were
used to describe the powder densification on the two machines. The calculated parameters revealed that the shorter compression
cycle of rotary machines results in poorer densification and lower tablet hardness at a given compression force. This is manifested
in poorer halving properties, which are influenced mainly by the hardness. Better densification improves the halving even
at lower tablet hardness. This demonstrates that these parameters can be good predictors of tablet halving properties. 相似文献
20.
土壤中微生物含量影响因素的统计方法分析 总被引:1,自引:0,他引:1
【目的】采用多元方差分析、多元线性回归分析、通径分析等统计方法,并利用多元统计方法对土壤中微生物含量进行分析。【方法】通过研究这3种常用统计方法的原理、应用条件、适用于解决的问题等,用不同的方法分析影响土壤中微生物含量的各种因素,利用SPSS软件求解。【结果】得出不同降雨量下土壤中的微生物含量存在差异性;铵态氮含量和海拔高度与变形菌门含量呈显著的线性关系,土壤中变形菌门含量随着铵态氮含量增多而增多,且铵态氮含量对变形菌门含量所起的直接作用最大;土壤中铵态氮含量、总氮量和海拔高度与放线菌门含量呈显著的线性关系,且均为负相关;其中总氮量对土壤中放线菌门含量的变化所起的负面作用最大,但铵态氮含量对放线菌门含量所起的直接作用最大。对比描述性统计方法与多元方差分析方法可知,应用描述性统计方法只能得出降雨量是影响土壤中不同细菌群落相对含量的因素之一,而不知降雨量对微生物含量变化的影响程度,6个梯度降雨量引起地显著差异究竟是由哪种微生物引起的,方差分析方法可以解决以上的问题。对比多元线性回归分析方法与通径分析方法可知,多元线性回归分析得出的相关系数只能表示铵态氮含量、总氮量和海拔与变形菌门含量(放线菌门含量)之间关系的密切程度,但无法解释和分析这种关系的构成和来源,通径分析方法可以解决这个问题。【结论】通径分析方法在分析相关问题时要优于多元线性回归分析方法,通径分析比多元线性回归分析方法更能体现因素对变形菌门含量(放线菌门含量)的直接影响和间接影响,分析结论更直观、更能说明问题。 相似文献