Comparison of Two Sample Tests Using Both Relative Efficiency and Power of Test

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.

THE INEFFICIENCY OF THE LEAST SQUARES ESTIMATOR AND ITS BOUND

It was suggested by Pantanen that the mean squared error may be used to measure the inefficiency of the least squares estimator. Styan[2] and Rao[3] et al. discussed this inefficiency and it's bound later. In this paper we propose a new inefficiency of the least squares estimator with the measure of generalized variance and obtain its bound.

Calculation method of quantum efficiency to TiO_2 nanocrystal photocatalysis reaction

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 ).

Axial response and material efficiency of tapered helical piles

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.

Potassium accumulation and translocation a mongrice genotypes in relation to internal potassium use efficiency(IKUE)

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%

LIMITING BEHAVIOR OF RECURSIVE M-ESTIMATORS IN MULTIVARIATE LINEAR REGRESSION MODELS AND THEIR ASYMPTOTIC EFFICIENCIES

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.

MATRIX NORM VERSIONS OF THE KANTOROVICH INEQUALITY AND ITS APPLICATIONS

In this paper we discuss the generalizations of the Kaotorovich inequality and obtain some generalized Kantorovich inequalities in the sense of matrix norm. We further illustrate how to use these inequalities to determine the lower bound of relative efficiency of the parameter estimate in linear model.

An Efficient Class of Estimators for the Finite Population Mean in Ranked Set Sampling

In this paper, we propose a class of estimators for estimating the finite population mean of the study variable under Ranked Set Sampling (RSS) when population mean of the auxiliary variable is known. The bias and Mean Squared Error (MSE) of the proposed class of estimators are obtained to first degree of approximation. It is identified that the proposed class of estimators is more efficient as compared to [1] estimator and several other estimators. A simulation study is carried out to judge the performances of the estimators.

Estimation of Turbulent Fluxes Using the Flux-Variance Method over an Alpine Meadow Surface in the Eastern Tibetan Plateau

The flux-variance similarity relation and the vertical transfer of scalars exhibit dissimilarity over different types of surfaces, resulting in different parameterization approaches of relative transport efficiency among scalars to estimate turbulent fluxes using the flux-variance method. We investigated these issues using eddycovariance measurements over an open, homogeneous and flat grassland in the eastern Tibetan Plateau in summer under intermediate hydrological conditions during rainy season. In unstable conditions, the temperature, water vapor, and CO2 followed the flux-variance similarity relation, but did not show in precisely the same way due to different roles （active or passive） of these scalars. Similarity constants of temperature, water vapor and CO2 were found to be 1.12, 1.19 and 1.17, respectively. Heat transportation was more eft% cient than water vapor and CO2. Based on the estimated sensible heat flux, five parameterization methods of relative transport efficiency of heat to water vapor and CO2 were examined to estimate latent heat and CO2 fluxes. The strategy of local determination of flux-variance similarity relation is recommended for the estimation of latent heat and CO2 fluxes. This approach is better for representing the averaged relative transport efficiency, and technically easier to apply, compared to other more complex ones.

Discussion of the Fluid Acceleration Quality of a Ducted Propulsion System on the Propulsive Performance

This paper focuses on the ducted propulsion with the accelerating nozzle,and discusses the influence of its fluid acceleration quality on its propulsive performances,including the hull efficiency,the relative rotative efficiency,the effective wake,and the thrust deduction factor.An actual ducted propulsion system is used as an example for computational analysis.The computational conditions are divided into four combinations,which are provided with different propeller pitches,cambers,and duct lengths.Themethod applied in this study is the Computational Fluid Dynamics(CFD)technology,and the contents of the calculation include the hull’s viscous resistance,the wave-making resistance,the propeller performance curve,and the self-propulsion simulation in order to obtain the ship’s effective wake,thrust deduction factor,hull efficiency,and relative rotative efficiency.The performance curve of the propeller and resistance estimation results are compared with the experimental values for determining the correctness of the self-propulsion simulation.According to the computational analysis,it is known that increasing the propeller pitch cannot effectively increase the hull efficiency.The duct acceleration quality can be reduced by shortening the duct length;hence,when the effective wake fraction and thrust deduction factor decrease,the hull efficiency is increased.In addition,the pressure inside the duct is relatively low if the acceleration quality of the duct is too high,which is unfavorable for controlling the propeller cavitation.Moreover,if the hull bottom in front of the propeller is tapered up from the front to the back at an overly steep angle,the thrust deduction factor will be too large and lead to a relatively low hull efficiency.

Estimation of scale parameters of logistic distribution by linear functions of sample quantiles

The large sample estimation of standard deviation of logistic distribution employs the asymptotically best linear unbiased estimators based on sample quantiles. The sample quantiles are established from a pair of single spacing. Finally, a table of the variances and efficiencies of the estimator for 5≤n≤65 is provided and comparison is made with other linear estimators.

Increasing yield potential through manipulating of an ARE1 ortholog related to nitrogen use efficiency in wheat by CRISPR/Cas9

Wheat(Triticum aestivum L.)is a staple food crop consumed by more than 30%of world population.Nitrogen(N)fertilizer has been applied broadly in agriculture practice to improve wheat yield to meet the growing demands for food production.However,undue N fertilizer application and the low N use efficiency(NUE)of modern wheat varieties are aggravating environmental pollution and ecological deterioration.Under nitrogen-limiting conditions,the rice(Oryza sativa)abnormal cytokinin response1 repressor1(are1)mutant exhibits increased NUE,delayed senescence and consequently,increased grain yield.However,the function of ARE1 ortholog in wheat remains unknown.Here,we isolated and characterized three TaARE1 homoeologs from the elite Chinese winter wheat cultivar ZhengMai 7698.We then used CRISPR/Cas9-mediated targeted mutagenesis to generate a series of transgene-free mutant lines either with partial or triple-null taare1 alleles.All transgene-free mutant lines showed enhanced tolerance to N starvation,and showed delayed senescence and increased grain yield in field conditions.In particular,the AABBdd and aabbDD mutant lines exhibited delayed senescence and significantly increased grain yield without growth defects compared to the wild-type control.Together,our results underscore the potential to manipulate ARE1 orthologs through gene editing for breeding of high-yield wheat as well as other cereal crops with improved NUE.

Changes in visibility with PM_(2.5) composition and relative humidity at a background site in the Pearl River Delta region

In fall–winter, 2007–2013, visibility and light scattering coefficients（b sp） were measured along with PM_（2.5）mass concentrations and chemical compositions at a background site in the Pearl River Delta（PRD） region. The daily average visibility increased significantly（p 〈 0.01） at a rate of 1.1 km/year, yet its median stabilized at ~13 km. No haze days occurred when the 24-hr mean PM_（2.5）mass concentration was below 75 μg/m^3. By multiple linear regression on the chemical budget of particle scattering coefficient（b sp）, we obtained site-specific mass scattering efficiency（MSE） values of 6.5 ± 0.2, 2.6 ± 0.3, 2.4 ± 0.7 and 7.3 ± 1.2 m2/g,respectively, for organic matter（OM）, ammonium sulfate（AS）, ammonium nitrate（AN） and sea salt（SS）. The reconstructed light extinction coefficient（b ext） based on the Interagency Monitoring of Protected Visual Environments（IMPROVE） algorithm with our site-specific MSE revealed that OM, AS, AN, SS and light-absorbing carbon（LAC） on average contributed 45.9% ± 1.6%,25.6% ± 1.2%, 12.0% ± 0.7%, 11.2% ± 0.9% and 5.4% ± 0.3% to light extinction, respectively.Averaged b ext displayed a significant reduction rate of 14.1/Mm·year（p 〈 0.05）; this rate would be 82% higher if it were not counteracted by increasing relative humidity（RH） and hygroscopic growth factor（f（RH）） at rates of 2.5% and 0.16/year-1（p 〈 0.01）, respectively, during the fall–winter, 2007–2013. This growth of RH and f（RH） partly offsets the positive effects of lowered AS in improving visibility, and aggravated the negative effects of increasing AN to impair visibility.

An Efficient Scrambled Estimator of Population Mean of Quantitative Sensitive Variable Using General Linear Transformation of Non-sensitive Auxiliary Variable

In the present paper,we propose an efficient scrambled estimator of population mean of quantitative sensitive study variable,using general linear transformation of nonsensitive auxiliary variable.Efficiency comparisons with the existing estimators have been carried out both theoretically and numerically.It has been found that our optimal scrambled estimator is always more efficient than most of the existing scrambled estimators and also it is more efficient than few other scrambled estimators under some conditions.

Forcibly Re-scrambled Randomized Response Model for Simultaneous Estimation of Means of Two Sensitive Variables

Recently,Ahmed et al.(Commun Stat Theory Methods 47(2):324-343,2018)have introduced the idea of simultaneously estimating means of two sensitive variables by collecting one scrambled response and another pseudo-response.In this paper,we extend their idea to the simultaneous estimation of two means by making use of the forced quantitative randomized response model of Gjestvang and Singh(Metrika 66(2):243-257,2007)but then re-scrambling the scrambled scores.This idea of re-scrambling already scrambled responses seems completely new in the field of randomized response sampling.The performance of the proposed forced quantitative randomized response model has been investigated analytically as well as empirically.

Measuring The Economic Performance of Enterprises From China,Poland,Bulgaria and North America by Data Envelopment Analysi

Recently several countries and district have been experiencing economic reforms which lead to very different results, among them China, Poland, Bulgaria and North America. It is necessary to inspect how the enterprise is running in these countries and what′s the difference between the enterprises from China and other countries. In this paper, an application of data envelopment analysis (DEA) for measuring and evaluating the economic operating efficiency of forty enterprises from four countries and district: China, Poland, Bulgaria and North America is presented. This non parametric method allows efficiency to be measured without having to specify either the form of the production function or the weights for the different inputs and outputs used. Furthermore, the correspondence evaluating results are analyzed.

An Efficient Algorithm for Processing Multi-Relation Queries in Relational Databases

After a relation scheme R is decomposed into the set of schemes ρ={R_1,...,R_n},we may pose queries as if R existed in the database,taking a join of R_i's,when it is necessary to implement the query.Suppose a query involves a set of attributes S(?)R,we want to find the smallest subset of ρ whose union includes S.We prove that the problem is NP-complete and present a polynomial-bounded approximation algorithm.A subset of ρ whose union includes S and has a decomposition into 3NF with a lossless join and preservation of dependencies is given in the paper.