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131.
A. M. Kagan 《Journal of Mathematical Sciences》1986,34(2):1482-1487
Summary Denote by
k
a class of familiesP={P} of distributions on the line R1 depending on a general scalar parameter , being an interval of R1, and such that the moments µ1()=xdP
,...,µ2k
()=x
2k
dP
are finite, 1 (), ..., k (), k+1 () ...,
k
() exist and are continuous, with 1 () 0, and
j
+1 ()= 1 ()
j
() +[2() -1()2]
j
()/ 1 (), J=2, ..., k. Let 1=¯x=x
1 + ... +x
n/n, 2=x
1
2 + ... +x
n
2/n, ...,
k
=(x
1
k
+ ... +x
n
k/n denote the sample moments constructed for a sample x1, ..., xn from a population with distribution Pg. We prove that the estimator of the parameter by the method of moments determined from the equation 1= 1() and depending on the observations x1, ..., xn only via the sample mean ¯x is asymptotically admissible (and optimal) in the class
k
of the estimators determined by the estimator equations of the form 0 () + 1 () 1 + ... +
k
()
k
=0 if and only ifP
k
.The asymptotic admissibility (respectively, optimality) means that the variance of the limit, as n (normal) distribution of an estimator normalized in a standard way is less than the same characteristic for any estimator in the class under consideration for at least one 9 (respectively, for every ).The scales arise of classes
1
2... of parametric families and of classes 1 2 ... of estimators related so that the asymptotic admissibility of an estimator by the method of moments in the class
k
is equivalent to the membership of the familyP in the class
k
.The intersection consists only of the families of distributions with densities of the form h(x) exp {C0() + C1() x } when for the latter the problem of moments is definite, that is, there is no other family with the same moments 1 (), 2 (), ...Such scales in the problem of estimating the location parameter were predicted by Linnik about 20 years ago and were constructed by the author in [1] (see also [2, 3]) in exact, not asymptotic, formulation.Translated from Problemy Ustoichivosti Stokhasticheskikh Modelei, pp. 41–47, 1981. 相似文献
132.
Csorna SE Mestayer MD Panvini RS Word GB Yi X Bean A Bobbink GJ Brock I Engler A Ferguson T Kraemer R Rippich C Sutton R Vogel H Bebek C Berkelman K Blucher E Cassel DG Copie T DeSalvo R DeWire JW Ehrlich R Galik RS Gilchriese MG Gittelman B Gray SW Halling AM Hartill DL Heltsley BK Holzner S Ito M Kandaswamy J Kowalewski R Kreinick DL Kubota Y Mistry NB Mueller J Nordberg E Ogg M Peterson D Perticone D Pisharody M Read K Riley D Silverman A Stein PC Stone S Sadoff AJ Avery P Besson D Bowcock T 《Physical review letters》1986,56(12):1222-1225
133.
Bebek C Berkelman K Blucher E Cassel DG Copie T DeSalvo R DeWire JW Ehrlich R Galik RS Gilchriese MG Gittelman B Gray SW Halling AM Hartill DL Heltsley BK Holzner S Ito M Kandaswamy J Kowalewski R Kreinick DL Kubota Y Mistry NB Mueller J Nordberg E Ogg M Peterson D Perticone D Pisharody M Read K Riley D Silverman A Stein PC Stone S Sadoff AJ Avery P Besson D Bowcock T Giles RT Hassard J Kinoshita K Pipkin FM Wilson R Haas P Hempstead M Jensen T Kagan H Kass R Behrends S Gentile T Guida JM 《Physical review letters》1986,56(18):1893-1896
134.
Algorithm for the calculation of the electronic structure of molecules by the expanded Hückel method
An algorithm is described for the calculation of quantum-chemical characteristics of molecules by the expanded Hückel method. The method for the calculation of the complete overlap matrix of Slater atomic orbitals of type ns, np, and nd was modified. 相似文献
135.
Il'chibaeva I. B. Kagan E. Sh. Tomilov A. P. 《Russian Journal of Electrochemistry》2002,38(9):1045-1046
The dimerization reaction that occurs during electrochemical methoxylation of cinnamic acid is analogous to photodimerization and leads to the formation of -truxillic acid in the following cathodic–anodic process: The radical cation that forms on the anode converts into a biradical on the cathode, which then undergoes dimerization to -truxillic acid with a current efficiency of 63% (in a diaphragmless electrolyzer). The current efficiency rises to 94% when an alternating current is used. In a diaphragm electrolyzer -truxillic acid fails to form. 相似文献
136.
Bean A Bobbink GJ Brock IC Engler A Ferguson T Kraemer RW Rippich C Vogel H Bebek C Berkelman K Blucher E Cassel DG Copie T DeSalvo R DeWire JW Ehrlich R Galik RS Gilchriese MG Gittelman B Gray SW Halling AM Hartill DL Heltsley BK Holzner S Ito M Kandaswamy J Kowalewski R Kreinick DL Kubota Y Mistry NB Mueller J Namjoshi R Nordberg E Ogg M Perticone D Peterson D Pisharody M Read K Riley D Silverman A Stone S Yi X Sadoff AJ Avery P Besson D Bowcock T Giles RT Hassard J Kinoshita K Pipkin FM 《Physical review letters》1987,58(3):183-186
137.
Acid chlorides react with SmI2 to give α-diketones. Various experiments show that the initially formed acyl radical is rapidly transformed into an acyl anion which is thus generated by quite an unusual route.This species acylates acid chlorides, aldehydes and ketones in situ to give α-diketones and α-ketols. There are some limitations to this acyl anion chemistry but the reactions are realized with a good efficiency at room temperature in THF solution. 相似文献
138.
Csorna SE Garren L Mestayer MD Panvini RS Yi X Alam MS Avery P Bebek C Berkelman K Cassel DG Copie T DeSalvo R DeWire JW Ehrlich R Ferguson T Galik R Gilchriese MG Gittelman B Halling M Hartill DL Holzner S Ito M Kadaswamy J Kreinick DL Kubota Y Mistry NB Nordberg E Ogg M Peterson D Perticone D Read K Silverman A Stein PC Stone S Kezun X Sadoff AJ Giles RT Hassard J Hempstead M Kinoshita K McKay WW Pipkin FM Wilson R Haas P Jensen T Kagan H Kass R Behrends S Gentile T Guida JM Guida JA Morrow F 《Physical review letters》1985,54(17):1894-1897
139.
140.