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201.
There are many situations where it is desired to make simultaneous tests or give simultaneous confidence intervals for linear combinations (contrasts) of population or treatment means. Somerville (1997, 1999) developed algorithms for calculating the critical values for a large class of simultaneous tests and simultaneous confidence intervals. Fortran 90 and SAS‐IML batch programs and interactive programs were developed. These programs calculate the critical values for 15 different simultaneous confidence interval procedures (and the corresponding simultaneous tests) and for arbitrary procedures where the user specifies a combination of one and two sided contrasts. The programs can also be used to obtain the constants for “step‐down” testing of multiple hypotheses. This paper gives examples of the use of the algorithms and programs and illustrates their versatility and generality. The designs need not be balanced, multiple covariates may be present and there may be many missing values. The use of multiple regression and dummy variables to obtain the required variance covariance matrix is illustrated. Under weak normality assumptions the methods are “exact” and make the use of approximate methods or “simulation” unnecessary. 相似文献
202.
Paul Somerville Tetsuhisa Miwa Wei Liu Anthony Hayter 《Biometrical journal. Biometrische Zeitschrift》2001,43(5):533-542
Lee and Spurrier (1995) present one‐sided and two‐sided confidence interval procedures for making successive comparisons between ordered treatments. Their procedures have important applications for problems where the treatments can be assumed to satisfy a simple ordering, such as for a sequence of increasing dose‐levels of a drug. The two‐sided procedure provides both upper and lower bounds on the differences between successive treatments, whereas the one‐sided procedure only provides lower bounds on these differences. However, the one‐sided procedure allows sharper inferences regarding which treatments can be declared to be better than their previous ones. In this paper we apply the results obtained in Hayter , Miwa , and Liu (2000) to develop a new procedure which combines the good aspects of both the one‐sided and the two‐sided procedures. This new procedure maintains the inferential sensitivity of the one‐sided procedure while also providing both upper and lower bounds on the differences between successive treatments. Some new critical points are needed which are tabulated for the balanced case where the sample sizes are all equal. The application of the new procedure is illustrated with an example. 相似文献
203.
宽幅播种下带间距对冬小麦衰老进程及产量的影响 总被引:2,自引:0,他引:2
在大田试验条件下以多穗型品种‘百农矮抗58’和大穗型品种‘兰考矮早八’为供试材料,研究了宽幅播种(播幅8 cm)种植方式下不同带间距7 cm(KF7)、12 cm(KF12)和17 cm(KF17)对冬小麦(Triticum aestivum)衰老进程及产量的影响。结果表明:与常规条播(行距20 cm,播幅1—2 cm)相比,宽幅带播种植方式的花后旗叶叶绿素降解缓慢,丙二醛(MDA)含量降低,抗氧化酶活性增强,成穗数和产量提高。宽幅带播下不同带间距处理间差异因品种类型而异,矮抗58品种叶绿素相对含量(SPAD)、过氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)活性整体呈现为KF12KF17KF7,兰考矮早八品种表现为KF7KF12KF17,而MDA变化规律则相反。试验条件下,多穗型品种矮抗58以KF12处理、大穗型品种兰考矮早八以KF7处理花后叶绿素含量高,MDA含量低,抗氧化酶活性强,叶片衰老进程缓慢,产量结构协调,最终产量最高。 相似文献
204.
Bt与EoNPV混用配比优劣性图谱分析 总被引:2,自引:0,他引:2
苏云金杆菌(Bt)和茶尺蠖核型多角体病毒(EoNPV)等,两类生物源杀虫剂常以复配混用方式应用.由于药效的迟缓,而明显表现出剂量-时间-致死作用复合特征.但目前尚缺乏与之相适应的混用配比优劣判别标准.受叶庆华等地学信息图谱分析和曹进等指纹图谱整体相似性分析理论和方法的启发,用室内人工饲养繁殖茶尺蠖2龄初—中期幼虫生物测定结果作为基础数据,分析研究了Bt与EoNPV混用的剂量-时间-致死作用复合特征,并进行了配比优劣性判别的尝试.首先将生物测定的有关结果输入SPSS统计分析软件包和Excel绘图软件,进行多因素方差分析,同时分别绘出不同药剂处理的,以剂量梯度为横轴,以累加死亡虫数为纵轴的不同观察时段害虫致死过程的曲线组图,简称时段药效信息图;再使用SPSS软件包进行单因素方差分析,提取出用于整体相似性比较的图谱单元Ⅰ和用于细节非相似性比较的图谱单元Ⅱ,且分别量化,由此得到相似值和非相似值,据此又分别算得相似系数和非相似系数;最后综合成一种混用配比优劣性总体判别指标,简称Q值.结果,Bt:EoNPV为9:1、7:3、4:1和2:3等4个混配处理的Q值依次为200、100、31.0和23.8,明显标示了其中“9:1”的Q值最大,被确认为最合理的混配处理.此结果与之前的研究相同.还对该图谱分析方法的可靠性以及应用的可行性等进行了讨论. 相似文献
205.
1IntroductionItiswellknownthatnervecellsworkinnoisyenvironment,andnoisesourcesrangingfrominternalthermalnoisetoexternalperturbation.Onepuzzlingproblemishowdonervecellsaccommodatenoiseincodingandtransforminginformation,recentresearchshowsthatnoisemayp… 相似文献
206.
Marker-assisted recurrent selection for cumulating additive and interactive QTLs in recombinant inbred lines 总被引:7,自引:0,他引:7
G. Charmet N. Robert M. R. Perretant G. Gay P. Sourdille C. Groos S. Bernard M. Bernard 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1999,99(7-8):1143-1148
A computer program has been designed to manage marker information in recombinant inbred-line populations. The objective is
to select pairs of inbred lines (either recombinant-inbred or doubled-haploid) to be intercrossed, in order to accumulate
all or most favourable alleles, either with additive effects or with interactive effects. The population size required to
have a 95% chance of obtaining the best line from a given cross is computed, taking into account the number of QTLs and the
probability that no recombination event occurs in any of the QTL confidence intervals. It is shown that the accuracy of QTL
location greatly affects selection efficiency and that a recurrent selection scheme is highly preferable for pyramiding many
QTLs. An application to the bread-making quality improvement of wheat is presented.
Received: 25 September 1998 / Accepted: 29 July 1999 相似文献
207.
To investigate the Zn status of inhabitants of the Czech Republic, 1155 serum and 132 hair samples were analyzed for zinc
content. Analyzed material was obtained from randomly selected volunteers of both sexes in the age range 6–65 yr. Subpopulations
from five regions were included in the study. Analyses of both materials were performed by Instrumental Neutron Activation
Analysis (INAA). Coanalyses of Standard Reference Materials (SRM) for quality control were performed. The results (mean 910
±276 Μg Zn/L serum and 189 ±45 Μg Zn/g hair) demonstrate satisfactory zinc status of the searched population. Significant
interregional differences and age-dependent differences, as well as sex-dependent differences have been detected by the use
of correlation analysis. On the basis of these results, serum Zn concentration results of individual categories according
to age and sex were evaluated, and on the grounds of mean ±2 standard deviations, indicative intervals were calculated. The
frequency of individual serum Zn concentrations proved that the population of the Czech Republic does not suffer from severe
zinc deficiency. On the other hand, about one-third of our inhabitants has their serum Zn concentrations below the cutoff
value of 800 Μg Zn/L serum, which means a marginal or mild Zn deficit of the organism. 相似文献
208.
209.
In this study, we have investigated the association between osteoporosis and osteocalcin (BGLAP) − 298 C>T, estrogen receptor 1 (ER1) 397 T>C, collagen type1 alpha 1 (Col1A1) 2046 G>T and calcitonin receptor (CALCR) 1340 T>C polymorphisms. Genomic DNA was obtained from 266 persons (158 osteoporotic and 108 healthy controls). Genomic DNA was extracted from EDTA-preserved peripheral venous blood of patients and controls by a salting-out method and analyzed by PCR-RFLP. As a result, there was no statistically significant difference in the genotype and allele frequencies of patients and controls for BGLAP − 298 C>T, Col1A1 2046 G>T, ER1 397 T>C and CALCR 1340 T>C polymorphisms. However, ER1 CC genotype compared with TT + TC genotypes was found to increase the two fold the risk of osteoporosis [p = 0.039, OR = 2.156, 95% CI (1.083–4.293)] and CALCR CC genotype compared with TT + TC genotypes was found to have protective effect against osteoporosis [p = 0.045, OR = 0.471, 95% CI (0.237–0.9372)]. In the combined genotype analysis, ER1/CALCR TCCC combined genotype was estimated to have protective effect against osteoporosis [p = 0.0125, OR = 0.323, 95% CI (0.1383–0.755)] whereas BGLAP/Col1A1 CCTT and ER1/CALCR CCTT combined genotypes were estimated as risk factors for osteoporosis in Turkish population (p = 0.027, p = 0.009 respectively). 相似文献
210.