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Relative Efficiencies of Optimal Designs in Four Dimensions Constructed Using Balanced Incomplete Block Designs
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作者 Kabue Timothy Gichuki John Gikonyo Kiguta 《Open Journal of Statistics》 2024年第5期439-449,共11页
Experimentally, the best design gives estimates of the desired effects and contrasts with maximum precision. Efficiency as a discriminating factor enables comparison of designs. The goal of Response Surface Methodolog... Experimentally, the best design gives estimates of the desired effects and contrasts with maximum precision. Efficiency as a discriminating factor enables comparison of designs. The goal of Response Surface Methodology (RSM) is the determination of the best settings of the in-put variables for a maximum (or a minimum) response within a region of interest, R. This calls for fitting a model that adequately represents the mean response since such a model, is then used to locate the optimum. D-, A-, E- and T-Optimal designs of a rotatable design of degree two in four dimensions constructed using balanced incomplete block designs (BIBD) when the number of replications is less than three times the number of pairs of treatments occur together in the design and their relative efficiencies to general designs are presented. D-optimal design had 88 runs after replicating the factorial part twice and the axial part thrice with an optimal variance of 0.6965612 giving an efficiency of 97.7% while for A- and T-optimal designs they are formed with 112 runs each obtained by replicating the factorial part two times and axial part six times. Their optimal variances are 0.05798174 and 1.29828 respectively, with efficiency of 71.8% for A-optimal and 87.5% for T-optimal design. E-optimal design was found to be the most efficient design with an only 32 runs comprising only of the factorial part and with an optimal variance of 0.4182000, attaining an efficiency of approximately 1%. This study proposes the adoption of the E-optimal design in estimating the parameters of a rotatable second-order degree model constructed using BIBD for less costs and time saving. 展开更多
关键词 Response Surface Methodology Optimal Designs relative efficiency
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ON BAHADUR-TYPE ASYMPTOTIC EFFICIENCY OF POINT ESTIMATORS UNDER IRREGULAR TRUNCATED DISTRIBUTION FAMILY 被引量:1
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作者 陈桂景 王尧弘 李宁宁 《Acta Mathematica Scientia》 SCIE CSCD 1996年第2期142-152,共11页
In this paper, the optimal convergence rates of point estimators have been found under the irregular truncated distribution family, and corresponding Bahadurtype asymptotic efficiencies have been established. It has b... In this paper, the optimal convergence rates of point estimators have been found under the irregular truncated distribution family, and corresponding Bahadurtype asymptotic efficiencies have been established. It has beed justified that commonly used estimators are all efficient in this sense. 展开更多
关键词 irregular truncated family Bahadnr-type asymptotic efficiency commonly used estimator.
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Application of a mixed DEA model to evaluate relative efficiency validity 被引量:2
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作者 FU Yu-wei YIN Hang YANG Gui-bin 《Journal of Marine Science and Application》 2005年第3期64-70,共7页
Data envelopment analysis(DEA) model is widely used to evaluate the relative efficiency of producers. It is a kind of objective decision method with multiple indexes. However, the two basic models frequently used at p... Data envelopment analysis(DEA) model is widely used to evaluate the relative efficiency of producers. It is a kind of objective decision method with multiple indexes. However, the two basic models frequently used at present, the C2R model and the C2GS2 model have limitations when used alone,resulting in evaluations that are often unsatisfactory. In order to solve this problem, a mixed DEA model is built and is used to evaluate the validity of the business efficiency of listed companies. An explanation of how to use this mixed DEA model is offered and its feasibility is verified. 展开更多
关键词 decision making units (DMU) efficiency evaluating mixed data envelopment analysis (DEA) model relative efficiency
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Numerical simulation of four-wave mixing efficiency and its induced relative intensity noise
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作者 陈伟 孟洲 +1 位作者 周会娟 罗洪 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第6期515-519,共5页
Four-wave mixing, as well as its induced intensity noise, is harmful to wavelength division multiplexing systems. The efficiency and the relative intensity noise of four-wave mixing are numerically simulated for the t... Four-wave mixing, as well as its induced intensity noise, is harmful to wavelength division multiplexing systems. The efficiency and the relative intensity noise of four-wave mixing are numerically simulated for the two-wave and the three-wave fiber transmissions. It is found that the efficiency decreases with the increase of both the frequency spacing and the fiber length, which can be explained using the quasi-phase-matching condition. Furthermore, the relative intensity noise decreases with the increase of frequency spacing, while it increases with the increase of fiber length, which is due to the considerable power loss of the pump light. This investigation presents a good reference for the practical application of wavelength division multiplexing systems. 展开更多
关键词 four-wuve mixing efficiency relative intensity noise phase matching
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The Limiting Distribution of the MLE for the Location Parameters in Nonregular Translation Distributions and Its Asymptotic Efficiency
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作者 成 平 《Northeastern Mathematical Journal》 CSCD 2001年第4期407-422,共16页
In this paper, we consider the location model Y = θ + 6, where θ is an unknown parameter, and e is the error belonging to the interval [a,b]. We assume that θhas the following density function: Then we give the lim... In this paper, we consider the location model Y = θ + 6, where θ is an unknown parameter, and e is the error belonging to the interval [a,b]. We assume that θhas the following density function: Then we give the limiting distribution of MLE θn for 1 < min(α,β) < 2 and consider the Bahadur asymptotic estimator. Since the results depend only on α,β,C1,C2 and are independent of the concrete form of f(x), they have adaptability. 展开更多
关键词 Bahadur asymptotic efficiency Nonregular uncommon support distri-bution MLE
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Asymptotic Efficiency of the Maximum Likelihood Estimator for the Box-Cox Transformation Model with Heteroscedastic Disturbances
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作者 Kazumitsu Nawata 《Open Journal of Statistics》 2016年第5期835-841,共8页
This paper considers the asymptotic efficiency of the maximum likelihood estimator (MLE) for the Box-Cox transformation model with heteroscedastic disturbances. The MLE under the normality assumption (BC MLE) is a con... This paper considers the asymptotic efficiency of the maximum likelihood estimator (MLE) for the Box-Cox transformation model with heteroscedastic disturbances. The MLE under the normality assumption (BC MLE) is a consistent and asymptotically efficient estimator if the “small ” condition is satisfied and the number of parameters is finite. However, the BC MLE cannot be asymptotically efficient and its rate of convergence is slower than ordinal order when the number of parameters goes to infinity. Anew consistent estimator of order is proposed. One important implication of this study is that estimation methods should be carefully chosen when the model contains many parameters in actual empirical studies. 展开更多
关键词 Maximum Likelihood Estimator (MLE) asymptotic efficiency Box-Cox Transformation Model HETEROSCEDASTICITY
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A new relative efficiency in parameter estimation for linear model
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作者 YANG Hu CHEN Zhu-liang 《Journal of Chongqing University》 CAS 2007年第2期141-145,共5页
A new relative efficiency of parameter estimation for generalized Gauss-Markov linear model was proposed. Its lower bound was also derived. Its properties were explored in comparison with three currently very popular ... A new relative efficiency of parameter estimation for generalized Gauss-Markov linear model was proposed. Its lower bound was also derived. Its properties were explored in comparison with three currently very popular relative efficiencies. The new relative efficiency not only reflects sensitively the error and loss caused by the substitution of the least square estimator for the best linear unbiased estimator, but also overcomes the disadvantage of weak dependence on the design matrix. 展开更多
关键词 linear model: narameter estimation: relative efficiency
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The Relative Efficiency of the Conditional Root Square Estimation of Parameter in Inhomogeneous Equality Restricted Linear Model
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作者 Xiu-Li Nong 《American Journal of Computational Mathematics》 2012年第3期235-239,共5页
This paper made a discuss on the relative efficiency of the generalized conditional root square estimation and the specific conditional root square estimation in paper [1,2] in inhomogeneous equality restricted linear... This paper made a discuss on the relative efficiency of the generalized conditional root square estimation and the specific conditional root square estimation in paper [1,2] in inhomogeneous equality restricted linear model. It is shown that the generalized conditional root squares estimation has not smaller the relative efficiency than the specific conditional root square estimation, by a constraint condition in root squares parameter, we compare bounds of them, thus, choose appropriate squares parameter, the generalized conditional root square estimation has the good performance on mean squares error. 展开更多
关键词 Generalized CONDITIONAL ROOT SQUARE ESTIMATION Specific CONDITIONAL ROOT SQUARE ESTIMATION relative efficiency
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Comparison of Two Sample Tests Using Both Relative Efficiency and Power of Test
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作者 Edith Uzoma Umeh Nkiru Obioma Eriobu 《Open Journal of Statistics》 2016年第2期331-345,共15页
This paper, comparison of two sample tests, is motivated by the fact that in the test of significant difference between two independent samples, numerous methods can be adopted;each may lead to significant different r... This paper, comparison of two sample tests, is motivated by the fact that in the test of significant difference between two independent samples, numerous methods can be adopted;each may lead to significant different results;this implies that wrong choice of test statistic could lead to erroneous conclusion. To prevent misleading information, there is a need for proper investigation of some selected methods for test of significant difference between variables/subjects most especially, independent samples. The paper examines the efficiency and sensitivity of four test statistics to ascertain which test performs better. Based on the results, the relative efficiency favours median test as being more efficient than modified median test for both symmetric and asymmetric distributions. In terms of power of test, median test is more sensitive than Modified Median (MMED) test since it has higher power irrespective of the sample sizes for both symmetric and asymmetric distribution. In terms of relative efficiency for asymmetric distribution Modified Mann-Whitney U test is more efficient than Mann-Whitney U test (MMWU), and then for symmetric distribution, Mann-Whitney U test (MMWU) is more efficient than Modified Mann-Whitney in sample size of 5;but for other sample sizes considered Modified Mann-Whitney U test (MMWU) is better than Mann-Whitney. Using power of test for both symmetric and asymmetric distributions, Mann-Whitney is more sensitive than Modified Mann-Whitney U test (MMWU) because it has higher power. 展开更多
关键词 ASYMMETRIC SYMMETRIC Nonparametric Test Two Sample Tests Power of Test relative efficiency
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RELATIVE ASYMPTOTICS FOR ORTHOGONAL MATRIX POLYNOMIALS WITH RESPECT TO A PERTURBED MATRIX MEASURE ON THE UNIT CIRCLE
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作者 Hossain O. Yakhlef Francisco Marcellán 《Approximation Theory and Its Applications》 2002年第4期1-19,共19页
Given a positive definite matrix measure Ω supported on the unit circle T, then main purpose of this paper is to study the asymptotic behavior of L n()L n(Ω) -1 and Φ n(z;)Φ n(z;Ω) -1 where(z)=Ω(z)+Mδ(z-w... Given a positive definite matrix measure Ω supported on the unit circle T, then main purpose of this paper is to study the asymptotic behavior of L n()L n(Ω) -1 and Φ n(z;)Φ n(z;Ω) -1 where(z)=Ω(z)+Mδ(z-w); |w|>1,M is a positive definite matrix and δ is the Dirac matrix measure. Here, L n(·) means the leading coefficient of the orthonormal matrix polynomials Φ n(z;·). Finally, we deduce the asymptotic behavior of Φ n(w;)Φ n(w;Ω)* in the case when M=I. 展开更多
关键词 relative asymptoticS FOR ORTHOGONAL MATRIX POLYNOMIALS WITH RESPECT TO A PERTURBED MATRIX MEASURE ON THE UNIT CIRCLE
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Asymptotic Consistency of the James-Stein Shrinkage Estimator
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作者 Alex Samuel Mungo Victor Mooto Nawa 《Open Journal of Statistics》 2023年第6期872-892,共21页
The study explores the asymptotic consistency of the James-Stein shrinkage estimator obtained by shrinking a maximum likelihood estimator. We use Hansen’s approach to show that the James-Stein shrinkage estimator con... The study explores the asymptotic consistency of the James-Stein shrinkage estimator obtained by shrinking a maximum likelihood estimator. We use Hansen’s approach to show that the James-Stein shrinkage estimator converges asymptotically to some multivariate normal distribution with shrinkage effect values. We establish that the rate of convergence is of order  and rate , hence the James-Stein shrinkage estimator is -consistent. Then visualise its consistency by studying the asymptotic behaviour using simulating plots in R for the mean squared error of the maximum likelihood estimator and the shrinkage estimator. The latter graphically shows lower mean squared error as compared to that of the maximum likelihood estimator. 展开更多
关键词 asymptotic CONSISTENCY CONVERGENCE efficiency Mean Squared Error SHRINKAGE
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Photosynthetic Light Utilization Efficiency, Water Relations and Leaf Growth of C3 and CAM Tropical Orchids under Natural Conditions 被引量:1
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作者 Shawn Tay Jie He Tim Wing Yam 《American Journal of Plant Sciences》 2015年第18期2949-2959,共11页
Native orchid species of Singapore in their natural conditions experience stress from high irradiance, high temperatures and periods of extended low rainfall, which impact orchid plant physiology and lead to reduced g... Native orchid species of Singapore in their natural conditions experience stress from high irradiance, high temperatures and periods of extended low rainfall, which impact orchid plant physiology and lead to reduced growth and productivity. In this study, it was found that there was a reduction in photochemical efficiency of photosystem II (PSII) in 6 native orchid species under high light (HL) and Bulbophyllum membranaceum under low light (LL). There was chronic photoinhibition in these 6 orchid species over a period of 3 months after transplanting onto the tree trunks without watering and fertilization, especially in Coelogynes mayeriana and Bulbophyllum membranaceum under both HL and LL. This chronic photoinhibition caused by sustained period of water deficit in their natural conditions was later reversed by natural re-watering conditions from higher rainfall. These results indicate that water deficit has a greater impact on photosynthetic light utilization efficiency than excess light. The present study also showed that after natural rewatering, relative water content (RWC) of leaves and pseudobulbs generally increased. During the natural re-watering, total leaf area also gradually increased and reached maximum expansion after 7 weeks under both HL and LL, with some exceptions due to leaf abscission or decline in total leaf area, possibly a strategy for water conservation. 展开更多
关键词 ORCHID CAM C3 PHOTOSYNTHETIC LIGHT Utilization efficiency Water relations and LEAF Growth
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LIMITING BEHAVIOR OF RECURSIVE M-ESTIMATORS IN MULTIVARIATE LINEAR REGRESSION MODELS AND THEIR ASYMPTOTIC EFFICIENCIES
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作者 缪柏其 吴月华 刘东海 《Acta Mathematica Scientia》 SCIE CSCD 2010年第1期319-329,共11页
Recursive algorithms are very useful for computing M-estimators of regression coefficients and scatter parameters. In this article, it is shown that for a nondecreasing ul (t), under some mild conditions the recursi... Recursive algorithms are very useful for computing M-estimators of regression coefficients and scatter parameters. In this article, it is shown that for a nondecreasing ul (t), under some mild conditions the recursive M-estimators of regression coefficients and scatter parameters are strongly consistent and the recursive M-estimator of the regression coefficients is also asymptotically normal distributed. Furthermore, optimal recursive M-estimators, asymptotic efficiencies of recursive M-estimators and asymptotic relative efficiencies between recursive M-estimators of regression coefficients are studied. 展开更多
关键词 asymptotic efficiency asymptotic normality asymptotic relative efficiency least absolute deviation least squares M-ESTIMATION multivariate linear optimal estimator reeursive algorithm regression coefficients robust estimation regression model
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Potassium accumulation and translocation a mongrice genotypes in relation to internal potassium use efficiency(IKUE)
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作者 LIU Jianxiang YANG Xiao’e Wu Lianghuan YANG Yu’ai College of Environmental and Resource Sciences,Zhejiang Univ,Hangzhou 310029,China 《Chinese Rice Research Newsletter》 2001年第1期10-11,共2页
Abiotie stresses including potassium deficiency are limitingfactors for increasing rice yield.Nine rice genotypes(Oryza Sativa L.,indica)differing in sensitivity to low Kstress selected from 200 volume-solution screen... Abiotie stresses including potassium deficiency are limitingfactors for increasing rice yield.Nine rice genotypes(Oryza Sativa L.,indica)differing in sensitivity to low Kstress selected from 200 volume-solution screening wereused in this study to examine accumulation and transloca-tion ofK.The powdery-muddy paddy soil tested contained 30.6mg·kgavailable K(1 N NHAcO extracted),1.92% 展开更多
关键词 IKUE Potassium accumulation and translocation a mongrice genotypes in relation to internal potassium use efficiency than
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Calculation method of quantum efficiency to TiO_2 nanocrystal photocatalysis reaction 被引量:4
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作者 XIE Yi bing, YUAN Chun wei (National Laboratory of Molecular & Biomolecular Electronics, Southeast University, Nanjing 210096, China.) 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2002年第1期70-75,共6页
The quantum yield is an important factor to evaluate the efficiency of photoreactor. This article gives an overall calculation method of the quantum efficiency( Φ ) and the apparent quantum efficiency( Φ a) to... The quantum yield is an important factor to evaluate the efficiency of photoreactor. This article gives an overall calculation method of the quantum efficiency( Φ ) and the apparent quantum efficiency( Φ a) to the TiO 2/UV photocatalysis system. Furthermore, for the immobility system (IS), the formulation of the faction of light absorbed by the TiO 2 thin film is proposed so as to calculate the quantum efficiency by using the measured value and theoretic calculated value of transmissivity (T). For the suspension system(SS), due to the difficulty to obtain the absorption coefficient ( α ) of TiO 2 particulates, the quantum efficiency is calculated by means of the relative photonic efficiency ( ζ r) and the standard quantum yield ( Φ standard ). 展开更多
关键词 photodegradation reaction quantum efficiency apparent quantum efficiency photonic efficiency relative photonic efficiency absorption coefficient
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Axial response and material efficiency of tapered helical piles 被引量:4
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作者 Hamid Mortazavi Bak Amir M.Halabian +1 位作者 Hamid Hashemolhosseini Mohammadali Rowshanzamir 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2021年第1期176-187,共12页
Different techniques have been proposed to increase the bearing capacity of open-ended piles.Welding helices to the shaft and tapering the pile shaft could be used simultaneously to enhance the static and dynamic beha... Different techniques have been proposed to increase the bearing capacity of open-ended piles.Welding helices to the shaft and tapering the pile shaft could be used simultaneously to enhance the static and dynamic behaviors of these piles.This paper subjects the bearing capacity,stiffness,frictional behavior,and material efficiency of the tapered helical piles to scrutiny.Tapered helical piles are introduced herein as an alternative option to improve the material efficiency of hollow piles.Based on the Taguchi method,a series of experiments was designed and conducted.The axial responses of tapered helical piles are also investigated using finite element analyses.The results derived from loadedisplacement curves and strain gages are used to characterize the axial compression responses of tapered helical piles.The effects of tapered angle,helices diameter and helices distance are examined using dimensionless parameters,and the degree of contribution of these factors is calculated on each of the enumerated variables individually.Experimental results show that the shaft friction resistance of tapered helical piles increases continuously with the pile head settlement.Furthermore,the effect of tapered wall on the shaft friction resistance is more tangible at low stress levels.The results showed that the relative material efficiency factor of the optimum pile could be 2.5 times that of unoptimized pile with a similar quantity of material. 展开更多
关键词 Tapered helical pile Axial response Bearing capacity Shaft resistance Initial tangent stiffness relative material efficiency Taguchi method
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On Asymptotic Properties of AIC Variants with Applications 被引量:1
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作者 Alex Karagrigoriou Kyriacos Mattheou Ilia Vonta 《Open Journal of Statistics》 2011年第2期105-109,共5页
In statistical modeling, the investigator is frequently confronted with the problem of selecting an appropriate model from a general class of candidate models. In recent years, various model selection procedures that ... In statistical modeling, the investigator is frequently confronted with the problem of selecting an appropriate model from a general class of candidate models. In recent years, various model selection procedures that can be used for the selection of the best possible model have been proposed. The AIC criterion [1] is considered the most popular tool for model selection although many competitors have been introduced over the years. One of the main drawbacks of AIC is its tendency to favor high dimensional models namely to overestimate the true model. A second issue that needs the attention of the investigator is the presence of outlying observations in the data set the inclusion of which in the statistical analysis may lead to erroneous results. In this work we propose AIC variants to handle the above weaknesses. Furthermore the asymptotic properties of the proposed criteria are investigated and a number of applications are discussed. 展开更多
关键词 AIC JACKKNIFE Censored Regression MODEL asymptotic efficiency
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Efficiency Rankings of MBA Programs in Indian Top Public Colleges 被引量:3
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作者 Patrick Jaska Vedamuthu Kulandai Swamy 《Journal of Modern Accounting and Auditing》 2013年第9期1275-1279,共5页
This study examines the relative efficiency of the top 20 Indian public colleges that offer MBAs. These colleges were chosen from a list provided by Careers 360, a magazine in India known for its university rankings. ... This study examines the relative efficiency of the top 20 Indian public colleges that offer MBAs. These colleges were chosen from a list provided by Careers 360, a magazine in India known for its university rankings. The purpose of this study was to evaluate the colleges on an efficiency basis rather than on a total score ranking scale as is the common practice of most publications that rank universities or programs. The ranking method used in this study is based on data envelopment analysis (DEA), a nonparametric procedure for evaluating entities based upon examining inputs in relation to outputs achieved. The rankings using DEA were somewhat different than those given by Careers 360. The results of the DEA analysis of this study rank the universities that are the most efficient at getting students the best salaries and return on investment (ROI) based on the inputs of diversity, work experience, and residency. The authors conclude, as previous studies have shown, that DEA analysis is a useful and non-biased method of comparing university programs. 展开更多
关键词 aniversity academic rankings relative efficiency data envelopment analysis (DEA)
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A Novel High Spectral Efficiency Waveform Coding-OVFDM 被引量:2
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作者 LI Daoben 《China Communications》 SCIE CSCD 2015年第2期61-73,共13页
Based on the Overlapped Multiplexing Principle[12],a frequency domain OVFDM(Overlapped Frequency Domain Multiplexing) Coding is proposed.By the data weighted shift overlapped version of any band-limited Multiplexing T... Based on the Overlapped Multiplexing Principle[12],a frequency domain OVFDM(Overlapped Frequency Domain Multiplexing) Coding is proposed.By the data weighted shift overlapped version of any band-limited Multiplexing Transfer Function H(f) the coding gain and spectral efficiency are both achieved.The heavier the overlap of the data weighted Multiplexing Transfer Function H(f),the higher the coding gain and spectral efficiency as well as the closer the output to the optimum complex Gaussian distribution.The bit error probability performance is estimated.The time domain OVTDM(Overlapped Time Domain Multiplexing) Coding,the dual of OVFDM in time domain is incidentally proposed as well.Both theoretical analysis and testified simulations show that OVFDM(OVTDM) is suitable for high spectral efficiency application and its spectral efficiency is only roughly linear to SNR rather than the well-known logarithm to SNR. 展开更多
关键词 overlapped multiplexing principle frequency domain coding waveform coding spectral efficiency shannon capacity dual relation OVFDM OVTDM
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Asymptotic Comparison of Method of Moments Estimators and Maximum Likelihood Estimators of Parameters in Zero-Inflated Poisson Model
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作者 G. Nanjundan T. Raveendra Naika 《Applied Mathematics》 2012年第6期610-616,共7页
This paper discusses the estimation of parameters in the zero-inflated Poisson (ZIP) model by the method of moments. The method of moments estimators (MMEs) are analytically compared with the maximum likelihood estima... This paper discusses the estimation of parameters in the zero-inflated Poisson (ZIP) model by the method of moments. The method of moments estimators (MMEs) are analytically compared with the maximum likelihood estimators (MLEs). The results of a modest simulation study are presented. 展开更多
关键词 ZERO-INFLATED POISSON Model Maximum LIKELIHOOD and MOMENT ESTIMATORS EM Algorithm asymptotic relative efficiency
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