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Using Pearson’s System of Curves to Approximate the Distributions of the Difference between Two Correlated Estimates of Signal-to-Noise Ratios: The Cases of Bivariate Normal and Bivariate Lognormal Distributions
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作者 Mohamed M. Shoukri 《Open Journal of Statistics》 2024年第3期207-227,共21页
Background: The signal-to-noise ratio (SNR) is recognized as an index of measurements reproducibility. We derive the maximum likelihood estimators of SNR and discuss confidence interval construction on the difference ... Background: The signal-to-noise ratio (SNR) is recognized as an index of measurements reproducibility. We derive the maximum likelihood estimators of SNR and discuss confidence interval construction on the difference between two correlated SNRs when the readings are from bivariate normal and bivariate lognormal distribution. We use the Pearsons system of curves to approximate the difference between the two estimates and use the bootstrap methods to validate the approximate distributions of the statistic of interest. Methods: The paper uses the delta method to find the first four central moments, and hence the skewness and kurtosis which are important in the determination of the parameters of the Pearsons distribution. Results: The approach is illustrated in two examples;one from veterinary microbiology and food safety data and the other on data from clinical medicine. We derived the four central moments of the target statistics, together with the bootstrap method to evaluate the parameters of Pearsons distribution. The fitted Pearsons curves of Types I and II were recommended based on the available data. The R-codes are also provided to be readily used by the readers. 展开更多
关键词 signal-to-noise ratio Bivariate Distributions Bootstrap Methods Delta Method Pearson System of Curves
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Acquisition Practice of High Signal-to-Noise Ratio in YTB Block of Sichuan Basin
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作者 Jun Wu Jiangli Chen +5 位作者 Zhong Li Zengyou Wu Hong Liu Yiwei Li Yong Tang Junguo Du 《Journal of Geoscience and Environment Protection》 2023年第6期229-236,共8页
YTB block in Sichuan basin is a favorable area to exploit oil and gas in shallow tight rock. 3D seismic project of this zone has two characteristics. Firstly, it has high requirements for the tolerance rate of the con... YTB block in Sichuan basin is a favorable area to exploit oil and gas in shallow tight rock. 3D seismic project of this zone has two characteristics. Firstly, it has high requirements for the tolerance rate of the construction process and the acquisition of high signal-to-noise ratio seismic data;Second, there are widely obstacles and noises that lead to difficult acquisition construction organization. In acquisition practice, high signal-to-noise ratio seismic data was obtained by reasonable design of construction scheme, optimization of excitation parameters, improvement of receiving conditions and optimization of obstacle crossing observation system. . 展开更多
关键词 Tight Oil and Gas Tolerance Rate High signal-to-noise ratio OBSTACLE
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Methodology for Obtaining Optimal Sleeve Friction and Friction Ratio Estimates from CPT Data
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作者 Erick Baziw 《International Journal of Geosciences》 CAS 2023年第3期290-303,共14页
Cone penetration testing (CPT) is a cost effective and popular tool for geotechnical site characterization. CPT consists of pushing at a constant rate an electronic penetrometer into penetrable soils and recording con... Cone penetration testing (CPT) is a cost effective and popular tool for geotechnical site characterization. CPT consists of pushing at a constant rate an electronic penetrometer into penetrable soils and recording cone bearing (q<sub>c</sub>), sleeve friction (f<sub>c</sub>) and dynamic pore pressure (u) with depth. The measured q<sub>c</sub>, f<sub>s</sub> and u values are utilized to estimate soil type and associated soil properties. A popular method to estimate soil type from CPT measurements is the Soil Behavior Type (SBT) chart. The SBT plots cone resistance vs friction ratio, R<sub>f</sub> [where: R<sub>f</sub> = (f<sub>s</sub>/q<sub>c</sub>)100%]. There are distortions in the CPT measurements which can result in erroneous SBT plots. Cone bearing measurements at a specific depth are blurred or averaged due to q<sub>c</sub> values being strongly influenced by soils within 10 to 30 cone diameters from the cone tip. The q<sub>c</sub>HMM algorithm was developed to address the q<sub>c</sub> blurring/averaging limitation. This paper describes the distortions which occur when obtaining sleeve friction measurements which can in association with q<sub>c</sub> blurring result in significant errors in the calculated R<sub>f</sub> values. This paper outlines a novel and highly effective algorithm for obtaining accurate sleeve friction and friction ratio estimates. The f<sub>c</sub> optimal filter estimation technique is referred to as the OSFE-IFM algorithm. The mathematical details of the OSFE-IFM algorithm are outlined in this paper along with the results from a challenging test bed simulation. The test bed simulation demonstrates that the OSFE-IFM algorithm derives accurate estimates of sleeve friction from measured values. Optimal estimates of cone bearing and sleeve friction result in accurate R<sub>f</sub> values and subsequent accurate estimates of soil behavior type. 展开更多
关键词 Cone Penetration Testing (CPT) Optimal estimation Geotechnical Site Characterization Sleeve Friction Cone Bearing Friction ratio Iterative Forward Modelling (IFM) Soil Behavior Type (SBT)
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Effective DOA Estimation Under Low Signal-to-Noise Ratio Based on Multi-Source Information Meta Fusion 被引量:2
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作者 Yun Wu Xiukun Li Zhimin Cao 《Journal of Beijing Institute of Technology》 EI CAS 2021年第4期377-396,共20页
Efficiently performing high-resolution direction of arrival(DOA)estimation under low signal-to-noise ratio(SNR)conditions has always been a challenge task in the literatures.Obvi-ously,in order to address this problem... Efficiently performing high-resolution direction of arrival(DOA)estimation under low signal-to-noise ratio(SNR)conditions has always been a challenge task in the literatures.Obvi-ously,in order to address this problem,the key is how to mine or reveal as much DOA related in-formation as possible from the degraded array outputs.However,it is certain that there is no per-fect solution for low SNR DOA estimation designed in the way of winner-takes-all.Therefore,this paper proposes to explore in depth the complementary DOA related information that exists in spa-tial spectrums acquired by different basic DOA estimators.Specifically,these basic spatial spec-trums are employed as the input of multi-source information fusion model.And the multi-source in-formation fusion model is composed of three heterogeneous meta learning machines,namely neural networks(NN),support vector machine(SVM),and random forests(RF).The final meta-spec-trum can be obtained by performing a final decision-making method.Experimental results illus-trate that the proposed information fusion based DOA estimation method can really make full use of the complementary information in the spatial spectrums obtained by different basic DOA estim-ators.Even under low SNR conditions,promising DOA estimation performance can be achieved. 展开更多
关键词 direction of arrival(DOA) signal-to-noise ratio(SNR) information fusion meta-learn-ing spatial spectrum
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An innovative detection method of high frequency BPSK signal with low signal-to-noise ratio 被引量:2
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作者 石硕 徐立振 +1 位作者 顾学迈 张宏莉 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2012年第6期93-99,共7页
Based on chaotic oscillator system, this paper proposes a novel method on high frequency low signal- to-noise ratio BPSK( Binary Phase Shift Keying) signal detection. Chaotic oscillator system is a typical non-lin- ... Based on chaotic oscillator system, this paper proposes a novel method on high frequency low signal- to-noise ratio BPSK( Binary Phase Shift Keying) signal detection. Chaotic oscillator system is a typical non-lin- ear system which is sensitive to periodic signals and immune to noise at the same time. Those properties make it possible to detect low signal-to-noise ratio signals. The BPSK signal is a common signal type which is widely used in modern communication. Starting from the analysis of advantages of chaotic, os~.illator system and signal features of the BPSK signal, we put forward a unique method that can detect low signar-to-noise ratio BPSK sig- nals with high frequency. The simulation results show that the novel method can dclct.t low signal-to-noise ratio BPSK signals with frequency in an order of magnitude of l0s Hz, and the input Signal-to-Noise Ratio threshold can be -20 dB. 展开更多
关键词 low signal-to-noise ratio signal detection chaotic oscillator system Binary Phase Shift Keying high frequency
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Signal-to-noise ratio of lensless ghost interference with thermal incoherent light 被引量:1
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作者 张二峰 戴宏毅 陈平形 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第2期229-234,共6页
Factors influencing the signal-to-noise ratio (SNR) of lensless ghost interference with thermal incoherent light are investigated. Our result shows that the SNR of lensless ghost interference is related to the trans... Factors influencing the signal-to-noise ratio (SNR) of lensless ghost interference with thermal incoherent light are investigated. Our result shows that the SNR of lensless ghost interference is related to the transverse length of the object, the position of the object in the imaging system and the transverse size of the light source. Furthermore, the effects of these factors on the SNR are discussed in detail by numerical simulations. 展开更多
关键词 ghost interference ghost imaging signal-to-noise ratio
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Noises and Signal-to-Noise Ratio of Nanosize EIS and ISFET Biosensors 被引量:2
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作者 Lusine Gasparyan Ilya Mazo +1 位作者 Vahan Simonyan Ferdinand Gasparyan 《Open Journal of Biophysics》 2020年第1期1-12,共12页
The results of comparative theoretical analyzes of the behavior of internal low-frequency noises, signal-to-noise ratio and sensitivity to DNA molecules for EIS and ISFET based nanosize biosensors are presented. It is... The results of comparative theoretical analyzes of the behavior of internal low-frequency noises, signal-to-noise ratio and sensitivity to DNA molecules for EIS and ISFET based nanosize biosensors are presented. It is shown that EIS biosensor is more sensitive to the presence of DNA molecules in aqueous solution than ISFET sensor. Internal electrical noises level decreases with the increase of concentration of DNA molecules in aqueous solution. In the frequency range 10&minus;3 - 103 Hz noises level for EIS sensor about in three orders is higher than for ISFET sensor. In the other hand, signal-to-noise ratio for capacitive EIS biosensor is much higher than for ISFET sensor. 展开更多
关键词 BIOSENSOR Noise Sensitivity signal-to-noise ratio
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Influence of signal-to-noise ratio on accuracy of spectral analysis by near infrared spectroscopy 被引量:1
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作者 ZHUANG Xin-gang SHI Xue-shun +3 位作者 LIU Hong-bo LIU Chang-ming ZHANG Peng-ju WANG Heng-fei 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2020年第3期211-216,共6页
As one of the important indicators of spectrometer,signal-to-noise ratio(SNR)reflects the ability of spectrometer to detect weak signals.To investigate the influence of SNR on the prediction accuracy of spectral analy... As one of the important indicators of spectrometer,signal-to-noise ratio(SNR)reflects the ability of spectrometer to detect weak signals.To investigate the influence of SNR on the prediction accuracy of spectral analysis,we first introduce the major factors affecting the spectral SNR.Taking green tea as an example,the influence of spectral SNR on the prediction accuracy of the origin identification model is analyzed by experiments.At the same time,the relationship between the spectral SNR and prediction accuracy of spectral analysis model is fitted.Based on this,the common methods for improving the spectral SNR are discussed.The results show that the accuracy of the prediction set model first decreases slowly,then decreases linearly,and finally tends to be flat as the spectral SNR decreases.Through calculation,in order to achieve the prediction accuracy of prediction model reaching 90%and 85%,the spectral SNR is required to be higher than 23.42 dB and 21.16 dB,respectively.The overall results provide certain parameters support for the development of new online analytical spectroscopic instruments,especially for the technical indicators of SNR. 展开更多
关键词 near infrared spectroscopy signal-to-noise ratio(SNR) partial least squares(PLS) spectral analysis green tea
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Enhancement of signal-to-noise ratio of ultracold polar NaCs molecular spectra by phase locking detection
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作者 王文浩 刘文良 +6 位作者 武寄洲 李玉清 王晓锋 刘艳艳 马杰 肖连团 贾锁堂 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第12期227-231,共5页
We report a method of high-sensitively detecting the weak signal in photoassociation (PA) spectra of ultracold NaCs molecules by phase sensitive-demodulated trap-loss spectra of Na atoms from a photomultiplier tube.... We report a method of high-sensitively detecting the weak signal in photoassociation (PA) spectra of ultracold NaCs molecules by phase sensitive-demodulated trap-loss spectra of Na atoms from a photomultiplier tube. We find that the signal-to-noise ratio (SNR) of the PA spectra is strongly dependent on the integration time and the sensitivity of the lock-in amplifier, and our results show reasonable agreement with the theoretical analyses of the SNR with the demodulation parameters. Meanwhile, we investigate the effect of the interaction time of the PA laser with the colliding Na-Cs atom pairs on the SNR of the PA spectra. The atom loss rate is dependent on both the PA-induced atom loss and the loading of the MOT. The high-sensitive detection of the excited ultracold NaCs molecules lays a solid foundation for further study of the formation and application of ultracold NaCs molecules. 展开更多
关键词 ultracold NaCs molecules PHOTOASSOCIATION high-resolution spectroscopy signal-to-noise ratio
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Signal-to-noise ratio of Raman signal measured by multichannel detectors
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作者 Xue-Lu Liu Yu-Chen Leng +2 位作者 Miao-Ling Lin Xin Cong Ping-Heng Tan 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第9期31-44,共14页
Raman spectroscopy has been widely used to characterize the physical properties of two-dimensional materials(2DMs).The signal-to-noise ratio(SNR or S/N ratio)of Raman signal usually serves as an important indicator to... Raman spectroscopy has been widely used to characterize the physical properties of two-dimensional materials(2DMs).The signal-to-noise ratio(SNR or S/N ratio)of Raman signal usually serves as an important indicator to evaluate the instrumental performance rather than Raman intensity itself.Multichannel detectors with outstanding sensitivity,rapid acquisition speed and low noise level have been widely equipped in Raman instruments for the measurement of Raman signal.In this mini-review,we first introduce the recent advances of Raman spectroscopy of 2DMs.Then we take the most commonly used CCD detector and IGA array detector as examples to overview the various noise sources in Raman measurements and analyze their potential influences on SNR of Raman signal in experiments.This overview can contribute to a better understanding on the SNR of Raman signal and the performance of multichannel detector for numerous researchers and instrumental design for industry,as well as offer practical strategies for improving spectral quality in routine measurement. 展开更多
关键词 multichannel detectors signal-to-noise ratio dark noise shot noise
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Calculation method of the signal-to-noise ratio attribute of seismic data based on structural orientation
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作者 Zhao Yan Mao Ning-Bo Chen Xu 《Applied Geophysics》 SCIE CSCD 2019年第4期455-462,560,共9页
At present,most signal-to-noise ratio(SNR)estimation methods can only calculate the global and not the local SNR of seismic data.This paper proposes a calculation method of a structure-oriented-based seismic SNR attri... At present,most signal-to-noise ratio(SNR)estimation methods can only calculate the global and not the local SNR of seismic data.This paper proposes a calculation method of a structure-oriented-based seismic SNR attribute.The purpose is to characterize the temporal and spatial variation of the seismic data SNR.First,the local slope parameters of the seismic events are calculated using a plane wave decomposition filter.Then,the singular value decomposition method is used to calculate the local seismic data SNR,thereby obtaining it in time and space.The proposed method overcomes the insufficiency of a conventional global SNR to characterize any local seismic data features and uses the SNR as an attribute of seismic data to more accurately describe the signal-noise energy distribution characteristics of seismic data in time and space.The results of a theoretical model test and real data processing show that the SNR attribute can be used not only for seismic data quality evaluation but also for analysis and evaluation of denoising methods. 展开更多
关键词 Seismic data signal-to-noise ratio attribute local slope singular value decomposition structure-oriented
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Signal-to-noise ratio comparison of angular signal radiography and phase stepping method
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作者 Wali Faiz 朱佩平 +4 位作者 胡仁芳 高昆 吴朝 鲍园 田扬超 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第12期173-178,共6页
Grating-based x-ray phase contrast imaging has the potential to be applied in future medical applications as it is compatible with both laboratory and synchrotron source. However, information retrieval methods are imp... Grating-based x-ray phase contrast imaging has the potential to be applied in future medical applications as it is compatible with both laboratory and synchrotron source. However, information retrieval methods are important because acquisition speed, scanning mode, image quality, and radiation dose depend on them. Phase-stepping (PS) is a widely used method to retrieve information, while angular signal radiography (ASR) is a newly established method. In this manuscript, signal-to-noise ratios (SNRs) of ASR are compared with that of PS. Numerical experiments are performed to validate theoretical results. SNRs comparison shows that for refraction and scattering images ASR has higher SNR than PS method, while for absorption image both methods have same SNR. Therefore, our conclusions would have guideline in future preclinical and clinical applications. 展开更多
关键词 angular signal radiography (ASR) phase-stepping (PS) signal-to-noise ratio (SNRs) information retrieval method
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Local Correlated Noise Improvement of Signal-to-Noise Ratio Gain in an Ensemble of Noisy Neuron
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作者 Tianquan Feng Qingrong Chen Ming Yi 《Journal of Intelligent Learning Systems and Applications》 2018年第3期104-119,共16页
We theoretically investigate the collective response of an ensemble of leaky integrate-and-fire neuron units to a noisy periodic signal by including local spatially correlated noise. By using the linear response theor... We theoretically investigate the collective response of an ensemble of leaky integrate-and-fire neuron units to a noisy periodic signal by including local spatially correlated noise. By using the linear response theory, we obtained the analytic expression of signal-to-noise ratio (SNR). Numerical simulation results show that the rms amplitude of internal noise can be increased up to?an optimal value where the output SNR reaches a maximum value. Due to the existence of the local spatially correlated noise in the units of the ensemble, the SNR gain of the collective ensemble response can exceed unity and can be optimized when the nearest-neighborhood correlation is negative. This nonlinear collective phenomenon of SNR gain amplification in an ensemble of leaky integrate-and-fire neuron units can be related to the array stochastic resonance (SR) phenomenon. Furthermore, we also show that the SNR gain can also be optimized by tuning the number of neuron units, frequency and?amplitude of the weak periodic signal. The present study illustrates the potential to utilize the local spatially correlation noise and the number of ensemble units for optimizing the collective response of the neuron to inputs, as well as a guidance in the design of information processing devices to weak signal detection. 展开更多
关键词 Array Stochastic Resonance signal-to-noise ratio LOCAL Correlation NOISY NEURONS
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Q-factor estimation in CMP gather and the continuous spectral ratio slope method 被引量:4
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作者 Wu Zong-Wei Wu Yi-Jia +1 位作者 Guo Si Xu Ming-Hua 《Applied Geophysics》 SCIE CSCD 2018年第3期481-490,共10页
The attenuation factor or quality factor(Q-factor or Q) has been used to measure the energy attenuation of seismic waves propagating in underground media. Many methods are used to estimate the Q-factor. We propose a m... The attenuation factor or quality factor(Q-factor or Q) has been used to measure the energy attenuation of seismic waves propagating in underground media. Many methods are used to estimate the Q-factor. We propose a method to calculate the Q-factor based on the prestack Q-factor inversion and the generalized S-transform. The proposed method specifies a standard primary wavelet and calculates the cumulative Q-factors; then, it finds the interlaminar Q-factors using the relation between Q and offset(QVO) and the Dix formula. The proposed method is alternative to methods that calculate interlaminar Q-factors after horizon picking. Because the frequency spectrum of each horizon can be extracted continuously on a 2D time–frequency spectrum, the method is called the continuous spectral ratio slope(CSRS) method. Compared with the other Q-inversion methods, the method offers nearly effortless computations and stability, and has mathematical and physical significance. We use numerical modeling to verify the feasibility of the method and apply it to real data from an oilfield in Ahdeb, Iraq. The results suggest that the resolution and spatial stability of the Q-profile are optimal and contain abundant interlaminar information that is extremely helpful in making lithology and fluid predictions. 展开更多
关键词 Quality FACTOR PRESTACK Q estimATION generalized S transform spectral ratio SLOPE METHOD Q versus offset
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Influence of Tire Dynamics on Slip Ratio Estimation of Independent Driving Wheel System 被引量:4
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作者 LI Jianqiu SONG Ziyou +1 位作者 WEI Yintao OUYANG Minggao 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2014年第6期1203-1210,共8页
The independent driving wheel system, which is composed of in-wheel permanent magnet synchronous motor(I-PMSM) and tire, is more convenient to estimate the slip ratio because the rotary speed of the rotor can be acc... The independent driving wheel system, which is composed of in-wheel permanent magnet synchronous motor(I-PMSM) and tire, is more convenient to estimate the slip ratio because the rotary speed of the rotor can be accurately measured. However, the ring speed of the tire ring doesn’t equal to the rotor speed considering the tire deformation. For this reason, a deformable tire and a detailed I-PMSM are modeled by using Matlab/Simulink. Moreover, the tire/road contact interface(a slippery road) is accurately described by the non-linear relaxation length-based model and the Magic Formula pragmatic model. Based on the relatively accurate model, the error of slip ratio estimated by the rotor rotary speed is analyzed in both time and frequency domains when a quarter car is started by the I-PMSM with a definite target torque input curve. In addition, the natural frequencies(NFs) of the driving wheel system with variable parameters are illustrated to present the relationship between the slip ratio estimation error and the NF. According to this relationship, a low-pass filter, whose cut-off frequency corresponds to the NF, is proposed to eliminate the error in the estimated slip ratio. The analysis, concerning the effect of the driving wheel parameters and road conditions on slip ratio estimation, shows that the peak estimation error can be reduced up to 75% when the LPF is adopted. The robustness and effectiveness of the LPF are therefore validated. This paper builds up the deformable tire model and the detailed I-PMSM models, and analyzes the effect of the driving wheel parameters and road conditions on slip ratio estimation. 展开更多
关键词 electric vehicle (EV) driving wheel system tire dynamics slip ratio estimation characteristic frequency low-pass filter (LPF)
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A Class of Estimators for Population Ratio in Simple Random Sampling Using Variable Transformation 被引量:2
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作者 A. C. Onyeka V. U. Nlebedim C. H. Izunobi 《Open Journal of Statistics》 2014年第4期284-291,共8页
This paper is an extension and generalization of the study carried out by [1] on the estimation of the population ratio (R) of the population means of two variables (y and x) under Simple Random Sampling (SRS) scheme,... This paper is an extension and generalization of the study carried out by [1] on the estimation of the population ratio (R) of the population means of two variables (y and x) under Simple Random Sampling (SRS) scheme, using a variable transformation of the auxiliary variable, x. All the six estimators proposed by [1] are easily identified as special cases of the proposed class of estimators. Asymptotic properties of the proposed class of estimators are derived theoretically and subsequently verified using empirical illustrations. Some of the proposed estimators are found to have relatively large gains in efficiency over the customary ratio estimator, ?for the given data set. 展开更多
关键词 Variable TRANSFORMATION ratio Product and Regression-Type estimATORS Mean Squared ERROR
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A new method for the estimation of fine-sediment resuspension ratios in estuaries-taking the turbidity maximum zone of the Changjiang(Yangtze) estuary as an example 被引量:1
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作者 沈志良 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2012年第5期791-795,共5页
Based on the principle of conservative matter removal in estuary,a new method is proposed for estimating the ratio of sediment resuspension in estuaries with fine suspended sediments in the turbidity maximum zone(TMZ)... Based on the principle of conservative matter removal in estuary,a new method is proposed for estimating the ratio of sediment resuspension in estuaries with fine suspended sediments in the turbidity maximum zone(TMZ) of the Changjiang(Yangtze) estuary during 2005.Results show that there was a range of 18.7%±27.9% to 73.9%±22.5% per annum of total suspended particulate matter(SPM),with an average of 49.2%.Nearly half of the particulate matter in the TMZ originates from sediment resuspension.This indicates that sediment resuspension is one of the major mechanisms involved in formation of the TMZ.Compared with traditional method for calculating these ratios in the estuary,this new method evaluates the dynamic variation of SPM content carried by river runoff from the river mouth to the ocean.The new method produced more reliable results than the traditional one and could produce a better estimation of resuspension flux for particulate matter in estuaries. 展开更多
关键词 sediment suspended particulate matter resuspension ratio estimate method turbidity maximumzone Changjiang (Yangtze) estuary
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Ratio-Cum-Product Estimator Using Multiple Auxiliary Attributes in Single Phase Sampling 被引量:4
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作者 John Kung’u Leo Odongo 《Open Journal of Statistics》 2014年第4期239-245,共7页
In this paper, we have proposed a class of ratio-cum-product estimator for estimating population mean of study variable for single phase sampling using multi-auxiliary attributes. The expressions for mean square error... In this paper, we have proposed a class of ratio-cum-product estimator for estimating population mean of study variable for single phase sampling using multi-auxiliary attributes. The expressions for mean square error are derived. An empirical study is given to compare the performance of the estimator with existing estimators. It has been found that the ratio-cum-product estimator using multiple auxiliary attributes is more efficient than mean per unit, product and ratio estimators using one auxiliary attribute, and Product and Ratio estimators using multiple auxiliary attributes in single phase sampling. 展开更多
关键词 ratio-Cum-Product estimATOR MULTIPLE AUXILIARY Attributes Single Phase Sampling Bi-Serial Correlation Coefficient
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Separate-Type Estimators for Estimating Population Ratio in Post-Stratified Sampling Using Variable Transformation
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作者 Aloy Chijioke Onyeka Chinyeaka Hostensia Izunobi Iheanyi Sylvester Iwueze 《Open Journal of Statistics》 2015年第1期27-34,共8页
The study proposes, along the line of [1], six separate-type estimators for estimating the population ratio of two variables in post-stratified sampling, using variable transformation. Properties of the proposed estim... The study proposes, along the line of [1], six separate-type estimators for estimating the population ratio of two variables in post-stratified sampling, using variable transformation. Properties of the proposed estimators were obtained up to first order approximations, both for achieved sample configurations (conditional argument) and over repeated samples of fixed size n (unconditional argument). Efficiency conditions, under which the proposed separate-type estimators would perform better than the associated customary separate-type estimators in terms of having smaller mean squared errors, were obtained. Furthermore, conditions under which some of the proposed separate-type estimators would perform better than other proposed separate-type estimators were also obtained. The optimum estimators among the proposed separate-type estimators were obtained and an empirical illustration confirmed the theoretical results. 展开更多
关键词 Variable Transformation Separate-Type estimATOR OPTIMUM estimATORS ratio Product and Regression-Type estimATORS Mean Squared Error
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Estimation of Population Ratio in Post-Stratified Sampling Using Variable Transformation
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作者 Aloy Chijioke Onyeka Chinyeaka Hostensia Izunobi Iheanyi Sylvester Iwueze 《Open Journal of Statistics》 2015年第1期1-9,共9页
Extending the work carried out by [1], this paper proposes six combined-type estimators of population ratio of two variables in post-stratified sampling scheme, using variable transformation. Properties of the propose... Extending the work carried out by [1], this paper proposes six combined-type estimators of population ratio of two variables in post-stratified sampling scheme, using variable transformation. Properties of the proposed estimators were obtained up to first order approximations,(on–1), both for achieved sample configurations (conditional argument) and over repeated samples of fixed size n (unconditional argument). Efficiency conditions were obtained. Under these conditions the proposed combined-type estimators would perform better than the associated customary combined-type estimator. Furthermore, optimum estimators among the proposed combined-type estimators were obtained both under the conditional and unconditional arguments. An empirical work confirmed the theoretical results. 展开更多
关键词 Variable TRANSFORMATION Combined-Type estimATOR ratio Product and Regression-Type estimATORS Mean Squared Error
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