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971.
A new approach of estimating parameters in multivariate models is introduced. A fitting function will be used. The idea is to estimate parameters so that the fitting function equals or will be close to its expected value. The function will be decomposed into two parts. From one part, which will be independent of the mean parameters, the dispersion matrix is estimated. This estimator is inserted in the second part which then yields the estimators of the mean parameters. The Growth Curve model, extended Growth Curve model and a multivariate variance components model will illustrate the approach. 相似文献
972.
Ashby Wedell M. Dechan R. Engel J. Ville G. Lunge Berthelot Ch. Blarez A. Joly O. N. Witt R. von Höslin E. Jacobsen Rowland Williams Watson Smith P. Julius Menschutkin E. Léger G. Vulpius Ludwig Storch B. Fischer O. Philipp Theodor Lehmann Julius Petri M. C. Traub C. Hock G. Burkhard E. Bosetti Robert T. Thomson Harry Napier Draper C. Draper J. H. Long Carpenter F. Stolba und Eugen Dietrich 《Fresenius' Journal of Analytical Chemistry》1888,27(1):36-61
Ohne Zusammenfassung 相似文献
973.
974.
C. Walther St. Becker G. Dietrich H.-J. Kluge M. Lindinger K. Lützenkirchen L. Schweikhard J. Ziegler 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1996,38(1):51-58
Photo fragmentation studies of stored mass selected metal cluster ions of a large size range are reported. The experimental method and the data evaluation are described in detail. Gold cluster ions were produced by laser vaporization and stored in a Penning trap. After size selection they were electronically excited by irradiation with a pulsed laser beam. Relaxation by evaporation of neutral atoms and dimers was observed as a function of photon energy. From these data upper and lower limits for dissociation energies are determined for Au+n (n=3 to 23). 相似文献
975.
The adaptive algorithm for the obstacle problem presented in this paper relies on the jump residual contributions of a standard
explicit residual-based a posteriori error estimator. Each cycle of the adaptive loop consists of the steps ‘SOLVE’, ‘ESTIMATE’,
‘MARK’, and ‘REFINE’. The techniques from the unrestricted variational problem are modified for the convergence analysis to
overcome the lack of Galerkin orthogonality. We establish R-linear convergence of the part of the energy above its minimal
value, if there is appropriate control of the data oscillations. Surprisingly, the adaptive mesh-refinement algorithm is the
same as in the unconstrained case of a linear PDE—in fact, there is no modification near the discrete free boundary necessary
for R-linear convergence. The arguments are presented for a model obstacle problem with an affine obstacle χ and homogeneous
Dirichlet boundary conditions. The proof of the discrete local efficiency is more involved than in the unconstrained case.
Numerical results are given to illustrate the performance of the error estimator. 相似文献
976.
N. Motohashi N. Ja. Chlopin Z. A. Pinskaja F. Ja. Anossow Je. I. Dundur Je. S. Firssowa K. Dietrich R. P. Forsyth W. F. Barfoot H. Wirtz A. S. Galvao A. Schwab G. Thanheiser Maria Waterkamp A. Brenner S. Bobayasi K. Kimura I. Tajiri Z. Shibata R. Paulus G. Ja. Weinberg M. W. Nifontowa 《Analytical and bioanalytical chemistry》1943,125(3-4):111-121
977.
978.
979.
Crystal structure measurements on the high-T
c
material YBa2Cu3O7 were carried out under pressure. Several X-ray reflections do not reveal a uniform shift with increasing pressure. Two models are presented, which show the experimental data to be consistent with an extensivec-axis orb-axis decrease, respectively. 相似文献
980.