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NON-PARAMETRIC ESTIMATION IN CONTAMINATED LINEAR MODEL 被引量:1
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作者 Chai Genxiang Sun Yan Yang XiaohanDept.ofAppl.Math.,TongjiUniv.,Shanghai200092 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2001年第2期195-202,共8页
In this paper, the following contaminated linear model is considered:y i=(1-ε)x τ iβ+z i, 1≤i≤n,where r.v.'s { y i } are contaminated with errors { z i }. To assume that the errors have the fin... In this paper, the following contaminated linear model is considered:y i=(1-ε)x τ iβ+z i, 1≤i≤n,where r.v.'s { y i } are contaminated with errors { z i }. To assume that the errors have the finite moment of order 2 only. The non parametric estimation of contaminated coefficient ε and regression parameter β are established, and the strong consistency and convergence rate almost surely of the estimators are obtained. A simulated example is also given to show the visual performance of the estimations. 展开更多
关键词 Contaminated data non parametric estimation strong consistency convergence rate almost surely.
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Parameters Estimation of a Bivariate Generalized Poisson Distribution with Applications to Metabolic Syndrome Data
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作者 Mohamed M. Shoukri 《Open Journal of Statistics》 2024年第5期467-480,共14页
Background: Bivariate count data are commonly encountered in medicine, biology, engineering, epidemiology and many other applications. The Poisson distribution has been the model of choice to analyze such data. In mos... Background: Bivariate count data are commonly encountered in medicine, biology, engineering, epidemiology and many other applications. The Poisson distribution has been the model of choice to analyze such data. In most cases mutual independence among the variables is assumed, however this fails to take into accounts the correlation between the outcomes of interests. A special bivariate form of the multivariate Lagrange family of distribution, names Generalized Bivariate Poisson Distribution, is considered in this paper. Objectives: We estimate the model parameters using the method of maximum likelihood and show that the model fits the count variables representing components of metabolic syndrome in spousal pairs. We use the likelihood local score to test the significance of the correlation between the counts. We also construct confidence interval on the ratio of the two correlated Poisson means. Methods: Based on a random sample of pairs of count data, we show that the score test of independence is locally most powerful. We also provide a formula for sample size estimation for given level of significance and given power. The confidence intervals on the ratio of correlated Poisson means are constructed using the delta method, the Fieller’s theorem, and the nonparametric bootstrap. We illustrate the methodologies on metabolic syndrome data collected from 4000 spousal pairs. Results: The bivariate Poisson model fitted the metabolic syndrome data quite satisfactorily. Moreover, the three methods of confidence interval estimation were almost identical, meaning that they have the same interval width. 展开更多
关键词 Lagrange Distributions Double Poisson Maximum Likelihood estimation Score Test of Independence Higher Order Moments non-parametric Bootstrap
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Parametric estimation of ultra wideband radar targets 被引量:1
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作者 Fan Ping Jing Zhanrong 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第3期499-503,共5页
Based on the analysis of impulse response properties, a scattering model of ultra wideband (UWB) radar targets is developed to estimate the target parameters exactly. With this model, two algorithms of multiple sign... Based on the analysis of impulse response properties, a scattering model of ultra wideband (UWB) radar targets is developed to estimate the target parameters exactly. With this model, two algorithms of multiple signal classification (MUSIC), and matrix pencil (MP), are introduced to calculate the scattering center parameters of targets and their performances are compared. The simulation experiments show that there are no differences in the estimation precision of MUSIC and MP methods when the signal-to-noise ratio (SNR) is larger than 13 dB. However, the MP method has a better performance than that of MUSIC method when the SNR is smaller than 13 dB. Besides, the time consuming of MP method is less than that of MUSIC method. Therefore, the MP algorithm is preferred for the parametric estimation of UWB radar targets. 展开更多
关键词 ultra wideband radar parametric estimation scattering center MODELING
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NONPARAMETRIC ESTIMATION OF BIVARIATE SURVIVAL FUNCTION UNDER THE COMPETING RISKS CASE
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作者 陈平 《Journal of Southeast University(English Edition)》 EI CAS 1992年第2期100-108,共9页
Estimation of the bivariate survival function under the competing risks caseis considered.We give an explicit formula for the estimator from a decomposition of thebivariate survival function based on competing risks,w... Estimation of the bivariate survival function under the competing risks caseis considered.We give an explicit formula for the estimator from a decomposition of thebivariate survival function based on competing risks,which is almost sure consistent. 展开更多
关键词 non-parametric statistics/competing RISKS BIVARIATE survival function NONparametric estimation ALMOST sure CONSISTENT
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Mixed-Effects Parametric Proportional Hazard Model with Generalized Log-Logistic Baseline Distribution
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作者 Maryrose Wausi Peter Samuel Musili Mwalili +1 位作者 Anthony Kibira Wanjoya Abdsalam Hassan Muse 《Journal of Data Analysis and Information Processing》 2023年第2期81-102,共22页
Clustered survival data are widely observed in a variety of setting. Most survival models incorporate clustering and grouping of data accounting for between-cluster variability that creates correlation in order to pre... Clustered survival data are widely observed in a variety of setting. Most survival models incorporate clustering and grouping of data accounting for between-cluster variability that creates correlation in order to prevent underestimate of the standard errors of the parameter estimators but do not include random effects. In this study, we developed a mixed-effect parametric proportional hazard (MEPPH) model with a generalized log-logistic distribution baseline. The parameters of the model were estimated by the application of the maximum likelihood estimation technique with an iterative optimization procedure (quasi-Newton Raphson). The developed MEPPH model’s performance was evaluated using Monte Carlo simulation. The Leukemia dataset with right-censored data was used to demonstrate the model’s applicability. The results revealed that all covariates, except age in PH models, were significant in all considered distributions. Age and Townsend score were significant when the GLL distribution was used in MEPPH, while sex, age and Townsend score were significant in MEPPH model when other distributions were used. Based on information criteria values, the Generalized Log-Logistic Mixed-Effects Parametric Proportional Hazard model (GLL-MEPPH) outperformed other models. 展开更多
关键词 Survival Analysis Generalized Log-Logistic parametric Proportional Hazard Mixed-Effects Monte Carlo Maximum Likelihood estimation
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A Comparison of the Performance of Various Estimators of Parametric Type1 Tobit Model 被引量:1
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作者 El Ouali Rahmani Abdelali Kaaouachi Said El Melhaoui 《Open Journal of Statistics》 2013年第1期1-4,共4页
In this paper, we use Monte Carlo simulations to compare parametric estimators of Type 1 Tobit model. In particular, we examine the performance for finite samples of three different estimators of simple Tobit model: t... In this paper, we use Monte Carlo simulations to compare parametric estimators of Type 1 Tobit model. In particular, we examine the performance for finite samples of three different estimators of simple Tobit model: the least squares (LS) estimator, the Heckman (H) estimator and the maximum likelihood (ML) estimator. These three estimators are consistent and asymptotically normal in the case where the density error is specified. However, these properties are sensitive to the situation where the error distribution is not specified. The purpose of this article is to determine properties of the three estimators, namely bias and convergence, by using Monte Carlo simulations. 展开更多
关键词 Type 1 TOBIT Model parametric estimation MONTE Carlo Simulation
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A parameter estimation based adaptive actuator failure compensation control scheme 被引量:1
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作者 Gang Tao Ruiyun Qi Chang Tan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第1期1-11,共11页
An adaptive actuator failure compensation control scheme is developed using an indirect adaptive control method,by calculating the controller parameters from adaptive estimates of system parameters and actuator failur... An adaptive actuator failure compensation control scheme is developed using an indirect adaptive control method,by calculating the controller parameters from adaptive estimates of system parameters and actuator failure parameters.A key technical issue is how to deal with the actuator failure uncertainties such as failure pattern,time and values.A complete parametrization covering all possible failures is used to solve this issue for adaptive parameter estimation.A simultaneous mapping from the estimated system/failure parameters to the controller parameters is employed to make the control system capable of ensuring the desired system performance under failures,which is verified by simulation results. 展开更多
关键词 actuator failure compensation adaptive control failure pattern and values parameter estimation stability and tracking uncertainty parametrization.
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Novel Channel Estimation Method in Broadband MIMO-OFDM Systems 被引量:1
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作者 焦慧颖 安建平 《Journal of Beijing Institute of Technology》 EI CAS 2007年第3期290-294,共5页
A least square (IS) parametric channel estimation method in broadband mt/ltiple input multiple output (MIMO) orthogonal frequency division multiplexing (OFDM) systems is proposed. The mean square error (MSE) p... A least square (IS) parametric channel estimation method in broadband mt/ltiple input multiple output (MIMO) orthogonal frequency division multiplexing (OFDM) systems is proposed. The mean square error (MSE) performance using optimal training pilots is also given, which proves the method can improve the estimation precision greatly in sparse channel.. Since such method needs the multi-path time delays information of the channel, the probabilistic data association (PDA) method is employed to estimate the time delay of each path. Simulation results show that both the bit error rate (BER) and the MSE performance of the proposed method are better than the traditional LS channel estimation method. 展开更多
关键词 multiple input multiple output (MIMO) orthogonal frequency division multiplexing (OFDM) channel estimation parametric channel model time delay estimation
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Small Sample Estimation in Dynamic Panel Data Models: A Simulation Study 被引量:1
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作者 Lorelied.A. Santos Erniel B. Barrios 《Open Journal of Statistics》 2011年第2期58-73,共16页
We used simulated data to investigate both the small and large sample properties of the within-groups (WG) estimator and the first difference generalized method of moments (FD-GMM) estimator of a dynamic panel data (D... We used simulated data to investigate both the small and large sample properties of the within-groups (WG) estimator and the first difference generalized method of moments (FD-GMM) estimator of a dynamic panel data (DPD) model. The magnitude of WG and FD-GMM estimates are almost the same for square panels. WG estimator performs best for long panels such as those with time dimension as large as 50. The advantage of FD-GMM estimator however, is observed on panels that are long and wide, say with time dimension at least 25 and cross-section dimension size of at least 30. For small-sized panels, the two methods failed since their optimality was established in the context of asymptotic theory. We developed parametric bootstrap versions of WG and FD-GMM estimators. Simulation study indicates the advantages of the bootstrap methods under small sample cases on the assumption that variances of the individual effects and the disturbances are of similar magnitude. The boostrapped WG and FD-GMM estimators are optimal for small samples. 展开更多
关键词 Dynamic Panel Data Model Within-Groups estimATOR First-Difference Generalized Method of MOMENTS estimATOR parametric BOOTSTRAP
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Software Cost Estimation Approaches: A Survey 被引量:1
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作者 Ismail M. Keshta 《Journal of Software Engineering and Applications》 2017年第10期824-842,共19页
The software cost estimation aims to predict the most realistic effort that is required to finish a software project and so it is critical to the success of a software project management. A Software Cost Estimation af... The software cost estimation aims to predict the most realistic effort that is required to finish a software project and so it is critical to the success of a software project management. A Software Cost Estimation affects nearly all management activities, including project bidding, resource allocation and project planning. It is affected by a number of factors, such as implementation efficiency, as well as how much the various reviews and studies completed prior to the software development stage cost. Accurate cost estimation will help us to complete the project on time and within budget. Accurate estimation is important because it has led to extensive research into the methods of software cost estimation. Some important software cost estimation methods have been studied in this research work. In addition, we have set out own criteria, which has been used to compare all the different selected methods. We have also given a score for each evaluation criteria, so that we can compare the different methods numerically for cost estimation. Our observations have shown that it is best to use a number of different estimating techniques or cost models, and then compare the results before determining the reasons for any of the large variations. None of the methods are necessarily better or worse than the others. We found, in fact, that their strengths and weaknesses often complement each other. Therefore, the main conclusion is that there is no one single technique that is best for every situation, and the results of a number of different approaches need to be carefully considered to discover what is the most likely to produce estimates that are realistic. 展开更多
关键词 Software COST estimation COCOMO MODEL parametric Models PUTNAM MODEL
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Bayesian Estimation in Dam Monitoring Networks 被引量:1
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作者 Joo Manuel Martins Casaca Pedro Jorge Bele Mateus Joeo de Jesus Isidoro Coelho 《Journal of Civil Engineering and Architecture》 2011年第2期185-190,共6页
A Bayesian estimator with informative prior distributions (a multi-normal and an inverted gamma distribution), adequate to displacement estimation at dam displacement monitoring networks, is presented. The hyper-par... A Bayesian estimator with informative prior distributions (a multi-normal and an inverted gamma distribution), adequate to displacement estimation at dam displacement monitoring networks, is presented. The hyper-parameters of the prior distributions are obtained by Bayesian empirical methods with non-informative meta-priors. The performances of the Bayes estimator and the classical generalized lest squares estimator are compared using two measurements of the horizontal monitoring network of a concrete gravity dam: the Penha Garcia dam (Portugal). In order to test the robustness of the two estimators, a gross error is added to one of the measured horizontal directions: the Bayes estimator proves to be significantly more robust than the classic maximum likelihood estimator. 展开更多
关键词 Bayes estimator hyper-parameter parametric elicitation prior distribution.
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Support Vector Machine Cost Estimation Model for Road Projects 被引量:1
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作者 Nabil Ibrahim El-Sawalhi 《Journal of Civil Engineering and Architecture》 2015年第9期1115-1125,共11页
A cost estimate is one of the most important steps in road project management. There are ranges of factors that mostly affect the final project cost. Many approaches were used to estimate project cost, which took into... A cost estimate is one of the most important steps in road project management. There are ranges of factors that mostly affect the final project cost. Many approaches were used to estimate project cost, which took into consideration probable project performance and risks. The aim is to improve the ability of construction managers to predict a parametric cost estimate for road projects using SVM (support vector machine). The work is based on collecting historical road executed cases. The 12 factors were identified to be the most important factors affecting the cost-estimating model. A total of 70 case studies from historical data were divided randomly into three sets: training set includes 60 cases, cross validation set includes three cases and testing set includes seven cases. The built model was successfully able to predict project cost to the AP (accuracy performance) of 95%. 展开更多
关键词 Road projects parametric cost estimation support vector machine cross validation.
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Estimation of ice resistance and sensitivity analysis for an icebreaker
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作者 FAN Tao YU Chenfang JIANG Yongxu 《Advances in Polar Science》 CSCD 2019年第4期399-405,共7页
The Lindqvist method is adopted to estimate the ice resistance for an icebreaker.The accuracy of the method is evaluated in a comparison of the calculated results with model test results.In addition to the estimation ... The Lindqvist method is adopted to estimate the ice resistance for an icebreaker.The accuracy of the method is evaluated in a comparison of the calculated results with model test results.In addition to the estimation of ice resistance,a sensitivity analysis based on the Lindqvist method is carried out.A full parametric model developed using CAESES software allows the convenient construction of many new hull lines.The primary factors relevant to ice resistance are embedded as design parameters in the full parametric model.Meanwhile,response surface methodology is adopted to give better insight into new hull lines.Results show that the ice resistance is more sensitive to the rake angle and waterline entrance angle.The aim of the present study is to improve the techniques of designing the hull forms of icebreakers. 展开更多
关键词 ICEBREAKER ice resistance estimation sensitivity analysis full parametric modeling Lindqvist method empirical formula
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Parametric Regression Approach for Gompertz Survival Times with Competing Risks
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作者 H.Rehman N.Chandra 《Communications on Applied Mathematics and Computation》 2022年第4期1175-1190,共16页
Regression models play a vital role in the study of data regarding survival of subjects.The Cox proportional hazards model for regression analysis has been frequently used in sur-vival modelling.In survival studies,it... Regression models play a vital role in the study of data regarding survival of subjects.The Cox proportional hazards model for regression analysis has been frequently used in sur-vival modelling.In survival studies,it is also possible that survival time may occur with multiple occurrences of event or competing risks.The situation of competing risks arises when there are more than one mutually exclusive causes of death(or failure)for the person(or subject).In this paper,we developed a parametric regression model using Gompertz distribution via the Cox proportional hazards model with competing risks.We discussed point and interval estimation of unknown parameters and cumulative cause-specific hazard function with maximum-likelihood method and Bayesian method of estimation.The Bayes estimates are obtained based on non-informative priors and symmetric as well as asym-metric loss functions.To observe the finite sample behaviour of the proposed model under both estimation procedures,we carried out a Monte Carlo simulation analysis.To demon-strate our methodology,we also included real data analysis. 展开更多
关键词 Competing risks Regression model Cause-specific hazard Gompertz distribution parametric model Bayesian estimation MCMC algorithm
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基于多项式Chirplet变换的线性调频引信干扰波形设计方法
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作者 闫晓鹏 张锦玉 +2 位作者 郝新红 李剑锋 代健 《兵工学报》 EI CAS CSCD 北大核心 2024年第2期504-515,共12页
针对现代战场环境下线性调频引信干扰技术的迫切需求,提出多项式Chirplet变换的方法实现低信噪比下对调频连续波无线电引信的信号参数估计,并针对调频连续波引信重构了干扰信号。基于线性小波变换原理,选取适当的核函数,将无线电引信信... 针对现代战场环境下线性调频引信干扰技术的迫切需求,提出多项式Chirplet变换的方法实现低信噪比下对调频连续波无线电引信的信号参数估计,并针对调频连续波引信重构了干扰信号。基于线性小波变换原理,选取适当的核函数,将无线电引信信号经过旋转与平移操作后进行短时傅里叶变换,再利用遗传算法求得变换核的最优参数,实现对调频连续波信号的参数估计,并重构干扰信号。仿真对比结果表明,该方法可以在较低信噪比下实现对调频连续波无线电引信信号载波频率、调制周期、最大频偏等参数进行精准估计,相较于周期调制类干扰,重构干扰信号能够以更低功率对调频引信产生较好的干扰效果。 展开更多
关键词 多项式Chirplet变换 参数估计 调频连续波 参数化时频分析 干扰重构
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Varying coefficient analysis for indeterminate species interactions with non-parametric estimation, exemplifying with a fig-fig wasp system 被引量:9
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作者 SHI Lei WANG RuiWu +3 位作者 ZHU LiXing ZEN WeiMing XU WangLi ZHENG Qi 《Chinese Science Bulletin》 SCIE EI CAS 2011年第24期2545-2552,共8页
Research on species interactions has generally assumed that species have a fixed interaction and therefore linear or non-linear parametric regression models (e.g. exponential, logistic) have been widely used to descri... Research on species interactions has generally assumed that species have a fixed interaction and therefore linear or non-linear parametric regression models (e.g. exponential, logistic) have been widely used to describe the species interaction. However, these models that describe the relationship between interacting species as a specific functional response might not be appropriate for real biological communities, for instance, in a chaotic system, when the species relationship varies among different situations. To allow a more accurate description of the relationship, we developed a species correlation model with varying coefficient analysis, in which a non-parametric estimation is applied to identify, as a function of related factors, variation in the correlation coefficient. This was applied to a fig-fig wasp model system. When the effect of the factors on the relationship can be described with parameters, the new method reduces to traditional parametric correlation analysis. In this way, the new method is more general and flexible for empirical data analyses, but different by allowing investigation of whether a species interaction varies with respect to factors, and of the factors that maintain or change the species interaction. This method will have important applications in both theoretical and applied research (e.g. epidemiology, community management). 展开更多
关键词 相互作用系数 非参数估计 混沌系统 无花果 物种 非线性参数 例证 小蜂
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基于压缩态光场的量子增强型光学相位追踪
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作者 孙小聪 李卫 +1 位作者 王雅君 郑耀辉 《物理学报》 SCIE EI CAS CSCD 北大核心 2024年第5期127-132,共6页
量子增强型光学相位追踪作为高精度跟踪和测量光学相位的量子光学技术,在目标定位、量子测距以及相控阵雷达和唢呐等领域中有着重要应用.本文提出一种基于压缩态光场的量子增强型光学相位追踪协议.采用中心波长为1064 nm的连续固体激光... 量子增强型光学相位追踪作为高精度跟踪和测量光学相位的量子光学技术,在目标定位、量子测距以及相控阵雷达和唢呐等领域中有着重要应用.本文提出一种基于压缩态光场的量子增强型光学相位追踪协议.采用中心波长为1064 nm的连续固体激光光源,结合光学参量振荡器以及Pound-Drever-Hall(PDH)锁定技术,制备得到初始压缩度为(8.0±0.2)dB的相位压缩态光场.通过信号调制及解调技术,实现对压缩态光场相位的控制,从而实现对光学相位0-2π范围内的量子增强型追踪.与经典协议相比,这一协议可以将相位追踪的噪声起伏抑制至散粒噪声基准以下至少6.27 dB,实现了相位追踪精度至少76.4%的量子增强.由于到达角估计、相控阵雷达、相控阵唢呐等应用领域对相位测量精度要求极高,这一协议有望将相位估计的精度提高至突破散粒噪声极限,为相关领域提供压缩光源,也为更高精度的空间定位及量子测距技术提供理论和实验基础. 展开更多
关键词 光学参量振荡 压缩态光场 相位估计 光学相位追踪
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仿射协变的G-质心
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作者 王贝贝 杨建伟 《计算机应用与软件》 北大核心 2024年第3期207-212,275,共7页
图像质心保持仿射协变,但仅可用于消除平移。为方便地提取仿射不变特征,需构造保持仿射协变且异于质心的类质心点。现有算法要么计算量大,要么对二值图像不适用。针对这种情况,提出G-质心,通过改造在极坐标系中图像质心的定义得到,引入... 图像质心保持仿射协变,但仅可用于消除平移。为方便地提取仿射不变特征,需构造保持仿射协变且异于质心的类质心点。现有算法要么计算量大,要么对二值图像不适用。针对这种情况,提出G-质心,通过改造在极坐标系中图像质心的定义得到,引入极径方向积分的变换函数,使得目前大多的类质心构造算法均是其特例。实验结果表明,通过引入中心投影类的变换函数,所得G-质心可比广义质心、交叉权重质心等算法具有更优的抗噪性能。 展开更多
关键词 特征提取 仿射协变 仿射变换参数恢复 质心 抗噪性
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基于单-多视图优化的足球球员三维姿态和体型估计
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作者 谢欢 刘纯平 季怡 《计算机工程》 CAS CSCD 北大核心 2024年第3期200-207,共8页
足球比赛场景的三维重建有助于观众自由切换视角,增加了互动性和沉浸感。针对足球比赛场景中的足球球员,提出一种三维姿态和体型估计方法。对球员的多视图图像使用训练好的部分注意力回归的三维人体估计(PARE)模型生成初始的三维姿态和... 足球比赛场景的三维重建有助于观众自由切换视角,增加了互动性和沉浸感。针对足球比赛场景中的足球球员,提出一种三维姿态和体型估计方法。对球员的多视图图像使用训练好的部分注意力回归的三维人体估计(PARE)模型生成初始的三维姿态和体型估计,并使用人工标注的二维关节点作为优化目标。单-多视图优化操作利用蒙皮多人线性模型(SMPL)和正交投影的可微性,将球员的三维姿态和体型参数映射到二维关节点,计算其与人工标注之间的差异,再使用神经网络的反向传播算法更新三维姿态和体型参数,持续这些过程直到差异最小化。在自建的足球球员多视图数据集上的实验结果表明,该方法能够有效估计足球球员的三维姿态和体型,与人体网格恢复、在循环中优化SMPL、PARE等方法相比,二维关节点精度在单视图上提高了9.2%~37.5%,在多视图交叉验证中提高了34.9%~54.1%。 展开更多
关键词 三维姿态和体型估计 参数化人体模型 单-多视图优化 反向传播 蒙皮多人线性模型
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非参数核密度估计模型预测双酚A的物种敏感度分布规律
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作者 杨瑞君 张楚 +4 位作者 杨评 冯承莲 李丹 陶建伟 叶璟 《生态毒理学报》 CAS CSCD 北大核心 2024年第4期120-130,共11页
双酚A(bisphenol A,BPA)已被证实是内分泌干扰物,可干扰生物体正常的激素功能,对生殖、发育和免疫系统产生不良影响。BPA进入环境后可能会对水生生物和陆地生物造成毒性效应,破坏生态平衡。针对BPA对水生生物的毒性特点,利用Python语言... 双酚A(bisphenol A,BPA)已被证实是内分泌干扰物,可干扰生物体正常的激素功能,对生殖、发育和免疫系统产生不良影响。BPA进入环境后可能会对水生生物和陆地生物造成毒性效应,破坏生态平衡。针对BPA对水生生物的毒性特点,利用Python语言,基于非参数核密度估计模型构建BPA淡水水生生物的敏感度分布曲线,选用4种传统参数模型进行对比,并推导出保护淡水水生生物的BPA水质基准建议值。结果表明,Python构建模型简单高效,相较于传统的参数模型,非参数核密度估计方法在推导BPA的水质基准建议值中更加稳健和精准,其中3种参数模型和非参数核密度估计模型计算得到的雌激素效应毒性的HC 5值分别为4.175、5.096、3.888和1.179μg·L^(-1);其他毒性的HC 5值为7.139、7.452、7.533和5.869μg·L^(-1)。非参数核密度估计的方法能够更好地构建物种敏感度分布曲线,为进一步研究BPA的水质基准和更好地保护淡水水生生物提供了有力支持,同时研究成果以期为我国地表水环境质量标准的制修订做出贡献。 展开更多
关键词 双酚A 淡水生物 雌激素效应 非参数核密度估计 物种敏感度分布 水质基准阈值
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