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Analysis of Progressively Type-Ⅱ Inverted Generalized Gamma Censored Data and Its Engineering Application
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作者 Refah Alotaibi Sanku Dey Ahmed Elshahhat 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第10期459-489,共31页
A novel inverted generalized gamma(IGG)distribution,proposed for data modelling with an upside-down bathtub hazard rate,is considered.In many real-world practical situations,when a researcher wants to conduct a compar... A novel inverted generalized gamma(IGG)distribution,proposed for data modelling with an upside-down bathtub hazard rate,is considered.In many real-world practical situations,when a researcher wants to conduct a comparative study of the life testing of items based on cost and duration of testing,censoring strategies are frequently used.From this point of view,in the presence of censored data compiled from the most well-known progressively Type-Ⅱ censoring technique,this study examines different parameters of the IGG distribution.From a classical point of view,the likelihood and product of spacing estimation methods are considered.Observed Fisher information and the deltamethod are used to obtain the approximate confidence intervals for any unknown parametric function of the suggestedmodel.In the Bayesian paradigm,the same traditional inferential approaches are used to estimate all unknown subjects.Markov-Chain with Monte-Carlo steps are considered to approximate all Bayes’findings.Extensive numerical comparisons are presented to examine the performance of the proposed methodologies using various criteria of accuracy.Further,using several optimality criteria,the optimumprogressive censoring design is suggested.To highlight how the proposed estimators can be used in practice and to verify the flexibility of the proposed model,we analyze the failure times of twenty mechanical components of a diesel engine. 展开更多
关键词 Inverted generalized gamma CENSORING spacing function LIKELIHOOD Bayesian optimal plan
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Evaluations of Chris-Jerry Data Using Generalized Progressive Hybrid Strategy and Its Engineering Applications
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作者 Refah Alotaibi Hoda Rezk Ahmed Elshahhat 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第9期3073-3103,共31页
A new one-parameter Chris-Jerry distribution,created by mixing exponential and gamma distributions,is discussed in this article in the presence of incomplete lifetime data.We examine a novel generalized progressively ... A new one-parameter Chris-Jerry distribution,created by mixing exponential and gamma distributions,is discussed in this article in the presence of incomplete lifetime data.We examine a novel generalized progressively hybrid censoring technique that ensures the experiment ends at a predefined period when the model of the test participants has a Chris-Jerry(CJ)distribution.When the indicated censored data is present,Bayes and likelihood estimations are used to explore the CJ parameter and reliability indices,including the hazard rate and reliability functions.We acquire the estimated asymptotic and credible confidence intervals of each unknown quantity.Additionally,via the squared-error loss,the Bayes’estimators are obtained using gamma prior.The Bayes estimators cannot be expressed theoretically since the likelihood density is created in a complex manner;nonetheless,Markov-chain Monte Carlo techniques can be used to evaluate them.The effectiveness of the investigated estimations is assessed,and some recommendations are given using Monte Carlo results.Ultimately,an analysis of two engineering applications,such as mechanical equipment and ball bearing data sets,shows the applicability of the proposed approaches that may be used in real-world settings. 展开更多
关键词 Chris-Jerry model generalized censoring likelihood and Bayes estimations MCMC algorithms engineering applications
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Computational Analysis of Novel Extended Lindley Progressively Censored Data
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作者 Refah Alotaibi Mazen Nassar Ahmed Elshahhat 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期2571-2596,共26页
A novel extended Lindley lifetime model that exhibits unimodal or decreasing density shapes as well as increasing,bathtub or unimodal-then-bathtub failure rates, named the Marshall-Olkin-Lindley (MOL) model is studied... A novel extended Lindley lifetime model that exhibits unimodal or decreasing density shapes as well as increasing,bathtub or unimodal-then-bathtub failure rates, named the Marshall-Olkin-Lindley (MOL) model is studied.In this research, using a progressive Type-II censored, various inferences of the MOL model parameters oflife are introduced. Utilizing the maximum likelihood method as a classical approach, the estimators of themodel parameters and various reliability measures are investigated. Against both symmetric and asymmetric lossfunctions, the Bayesian estimates are obtained using the Markov Chain Monte Carlo (MCMC) technique with theassumption of independent gamma priors. From the Fisher information data and the simulatedMarkovian chains,the approximate asymptotic interval and the highest posterior density interval, respectively, of each unknownparameter are calculated. Via an extensive simulated study, the usefulness of the various suggested strategies isassessedwith respect to some evaluationmetrics such as mean squared errors, mean relative absolute biases, averageconfidence lengths, and coverage percentages. Comparing the Bayesian estimations based on the asymmetric lossfunction to the traditional technique or the symmetric loss function-based Bayesian estimations, the analysisdemonstrates that asymmetric loss function-based Bayesian estimations are preferred. Finally, two data sets,representing vinyl chloride and repairable mechanical equipment items, have been investigated to support theapproaches proposed and show the superiority of the proposed model compared to the other fourteen lifetimemodels. 展开更多
关键词 Marshall-Olkin-Lindleymodel reliability inference Bayesian and classical inference progressive Type-II censoring
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Bayesian and Non-Bayesian Analysis for the Sine Generalized Linear Exponential Model under Progressively Censored Data
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作者 Naif Alotaibi A.S.Al-Moisheer +2 位作者 Ibrahim Elbatal Mohammed Elgarhy Ehab M.Almetwally 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第9期2795-2823,共29页
This article introduces a novel variant of the generalized linear exponential(GLE)distribution,known as the sine generalized linear exponential(SGLE)distribution.The SGLE distribution utilizes the sine transformation ... This article introduces a novel variant of the generalized linear exponential(GLE)distribution,known as the sine generalized linear exponential(SGLE)distribution.The SGLE distribution utilizes the sine transformation to enhance its capabilities.The updated distribution is very adaptable and may be efficiently used in the modeling of survival data and dependability issues.The suggested model incorporates a hazard rate function(HRF)that may display a rising,J-shaped,or bathtub form,depending on its unique characteristics.This model includes many well-known lifespan distributions as separate sub-models.The suggested model is accompanied with a range of statistical features.The model parameters are examined using the techniques of maximum likelihood and Bayesian estimation using progressively censored data.In order to evaluate the effectiveness of these techniques,we provide a set of simulated data for testing purposes.The relevance of the newly presented model is shown via two real-world dataset applications,highlighting its superiority over other respected similar models. 展开更多
关键词 Sine G family generalized linear failure rate progressively censored data MOMENTS maximum likelihood estimation Bayesian estimation simulation
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Censored Composite Conditional Quantile Screening for High-Dimensional Survival Data
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作者 LIU Wei LI Yingqiu 《应用概率统计》 CSCD 北大核心 2024年第5期783-799,共17页
In this paper,we introduce the censored composite conditional quantile coefficient(cC-CQC)to rank the relative importance of each predictor in high-dimensional censored regression.The cCCQC takes advantage of all usef... In this paper,we introduce the censored composite conditional quantile coefficient(cC-CQC)to rank the relative importance of each predictor in high-dimensional censored regression.The cCCQC takes advantage of all useful information across quantiles and can detect nonlinear effects including interactions and heterogeneity,effectively.Furthermore,the proposed screening method based on cCCQC is robust to the existence of outliers and enjoys the sure screening property.Simulation results demonstrate that the proposed method performs competitively on survival datasets of high-dimensional predictors,particularly when the variables are highly correlated. 展开更多
关键词 high-dimensional survival data censored composite conditional quantile coefficient sure screening property rank consistency property
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Nonparametric Statistical Feature Scaling Based Quadratic Regressive Convolution Deep Neural Network for Software Fault Prediction
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作者 Sureka Sivavelu Venkatesh Palanisamy 《Computers, Materials & Continua》 SCIE EI 2024年第3期3469-3487,共19页
The development of defect prediction plays a significant role in improving software quality. Such predictions are used to identify defective modules before the testing and to minimize the time and cost. The software w... The development of defect prediction plays a significant role in improving software quality. Such predictions are used to identify defective modules before the testing and to minimize the time and cost. The software with defects negatively impacts operational costs and finally affects customer satisfaction. Numerous approaches exist to predict software defects. However, the timely and accurate software bugs are the major challenging issues. To improve the timely and accurate software defect prediction, a novel technique called Nonparametric Statistical feature scaled QuAdratic regressive convolution Deep nEural Network (SQADEN) is introduced. The proposed SQADEN technique mainly includes two major processes namely metric or feature selection and classification. First, the SQADEN uses the nonparametric statistical Torgerson–Gower scaling technique for identifying the relevant software metrics by measuring the similarity using the dice coefficient. The feature selection process is used to minimize the time complexity of software fault prediction. With the selected metrics, software fault perdition with the help of the Quadratic Censored regressive convolution deep neural network-based classification. The deep learning classifier analyzes the training and testing samples using the contingency correlation coefficient. The softstep activation function is used to provide the final fault prediction results. To minimize the error, the Nelder–Mead method is applied to solve non-linear least-squares problems. Finally, accurate classification results with a minimum error are obtained at the output layer. Experimental evaluation is carried out with different quantitative metrics such as accuracy, precision, recall, F-measure, and time complexity. The analyzed results demonstrate the superior performance of our proposed SQADEN technique with maximum accuracy, sensitivity and specificity by 3%, 3%, 2% and 3% and minimum time and space by 13% and 15% when compared with the two state-of-the-art methods. 展开更多
关键词 Software defect prediction feature selection nonparametric statistical Torgerson-Gower scaling technique quadratic censored regressive convolution deep neural network softstep activation function nelder-mead method
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Exact Tail Asymptotics for a Queueing System with a Retrial Orbit and Batch Service
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作者 Huijun Lu 《Applied Mathematics》 2024年第6期406-420,共15页
This paper discusses a queueing system with a retrial orbit and batch service, in which the quantity of customers’ rooms in the queue is finite and the space of retrial orbit is infinite. When the server starts servi... This paper discusses a queueing system with a retrial orbit and batch service, in which the quantity of customers’ rooms in the queue is finite and the space of retrial orbit is infinite. When the server starts serving, it serves all customers in the queue in a single batch, which is the so-called batch service. If a new customer or a retrial customer finds all the customers’ rooms are occupied, he will decide whether or not to join the retrial orbit. By using the censoring technique and the matrix analysis method, we first obtain the decay function of the stationary distribution for the quantity of customers in the retrial orbit and the quantity of customers in the queue. Then based on the form of decay rate function and the Karamata Tauberian theorem, we finally get the exact tail asymptotics of the stationary distribution. 展开更多
关键词 Exact Tail Asymptotics Batch Service Censoring Technique Matrix Analysis Method Karamata Tauberian Theorem
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Using Extreme Value Theory Approaches to Estimate High Quantiles for Stroke Data
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作者 Justin Ushize Rutikanga Aliou Diop Charline Uwilingiyimana 《Open Journal of Statistics》 2024年第1期150-162,共13页
This paper aims to explore the application of Extreme Value Theory (EVT) in estimating the conditional extreme quantile for time-to-event outcomes by examining the functional relationship between ambulatory blood pres... This paper aims to explore the application of Extreme Value Theory (EVT) in estimating the conditional extreme quantile for time-to-event outcomes by examining the functional relationship between ambulatory blood pressure trajectories and clinical outcomes in stroke patients. The study utilizes EVT to analyze the functional connection between ambulatory blood pressure trajectories and clinical outcomes in a sample of 297 stroke patients. The 24-hour ambulatory blood pressure measurement curves for every 15 minutes are considered, acknowledging a censored rate of 40%. The findings reveal that the sample mean excess function exhibits a positive gradient above a specific threshold, confirming the heavy-tailed distribution of data in stroke patients with a positive extreme value index. Consequently, the estimated conditional extreme quantile indicates that stroke patients with higher blood pressure measurements face an elevated risk of recurrent stroke occurrence at an early stage. This research contributes to the understanding of the relationship between ambulatory blood pressure and recurrent stroke, providing valuable insights for clinical considerations and potential interventions in stroke management. 展开更多
关键词 Censored Data Conditional Extreme Quantile Kernel Estimator Weibull Tail Coefficient
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Reliability Analysis of HEE Parameters via Progressive Type-II Censoring with Applications
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作者 Heba S.Mohammed Mazen Nassar +1 位作者 Refah Alotaibi Ahmed Elshahhat 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第12期2761-2793,共33页
A new extended exponential lifetime model called Harris extended-exponential(HEE)distribution for data modelling with increasing and decreasing hazard rate shapes has been considered.In the reliability context,researc... A new extended exponential lifetime model called Harris extended-exponential(HEE)distribution for data modelling with increasing and decreasing hazard rate shapes has been considered.In the reliability context,researchers prefer to use censoring plans to collect data in order to achieve a compromise between total test time and/or test sample size.So,this study considers both maximum likelihood and Bayesian estimates of the Harris extended-exponential distribution parameters and some of its reliability indices using a progressive Type-II censoring strategy.Under the premise of independent gamma priors,the Bayesian estimation is created using the squared-error and general entropy loss functions.Due to the challenging form of the joint posterior distribution,to evaluate the Bayes estimates,samples from the full conditional distributions are generated using Markov Chain Monte Carlo techniques.For each unknown parameter,the highest posterior density credible intervals and asymptotic confidence intervals are also determined.Through a simulated study,the usefulness of the various suggested strategies is assessed.The optimal progressive censoring plans are also shown,and various optimality criteria are investigated.Two actual data sets,taken from engineering and veterinary medicine areas,are analyzed to show how the offered point and interval estimators can be used in practice and to verify that the proposed model furnishes a good fit than other lifetimemodels:alpha power exponential,generalized-exponential,Nadarajah-Haghighi,Weibull,Lomax,gamma and exponential distributions.Numerical evaluations revealed that in the presence of progressively Type-II censored data,the Bayes estimation method against the squared-error(symmetric)loss is advised for getting the point and interval estimates of the HEE distribution. 展开更多
关键词 Harris extended-exponential model progressive Type-II censoring RELIABILITY maximum likelihood MCMC techniques Monte Carlo experiments
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Ⅰ型左删失下Topp-Leone分布的参数及可靠度函数的估计
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作者 龙沁怡 徐丽平 《Chinese Quarterly Journal of Mathematics》 2023年第1期97-110,共14页
Firstly, the maximum likelihood estimate and asymptotic confidence interval of the unkown parameter for the Topp-Leone distribution are obtained under Type-I left censored samples, furthermore, the asymptotic confiden... Firstly, the maximum likelihood estimate and asymptotic confidence interval of the unkown parameter for the Topp-Leone distribution are obtained under Type-I left censored samples, furthermore, the asymptotic confidence interval of reliability function is obtained based on monotonicity. Secondly, under different loss functions, the Bayesian estimates of the unkown parameter and reliability function are obtained, and the expected mean square errors of Bayesian estimates are calculated. Monte-Carlo method is used to calculate the mean values and relative errors of the estimates. Finally, an example of life data is analyzed by using the statistical method in this paper. 展开更多
关键词 Topp-Leone distribution Type-I left censored samples Maximum likelihood estimate Bayesian estimate
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工业企业低碳生产意愿与行为研究 被引量:21
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作者 朱淀 王晓莉 童霞 《中国人口·资源与环境》 CSSCI 北大核心 2013年第2期72-81,共10页
工业企业作为低碳生产的主体,其形成低碳生产意愿直至实施低碳生产行为过程中受到政府、ISO14000环境管理标准、市场需求以及企业管理者、企业规模、技术能力及能源消耗等主要因素影响。本文以江苏省苏南地区的353家工业企业为案例,分... 工业企业作为低碳生产的主体,其形成低碳生产意愿直至实施低碳生产行为过程中受到政府、ISO14000环境管理标准、市场需求以及企业管理者、企业规模、技术能力及能源消耗等主要因素影响。本文以江苏省苏南地区的353家工业企业为案例,分别运用带罚函数的二元Logistic模型和Interval Censored模型,将企业管理者、企业规模和注册类型、技术能力、能源消耗特征以及政府、ISO14000环境管理标准和市场需求等企业内外部的各主要因素共同纳入其中,分析这些主要因素是否影响了我国工业企业低碳生产意愿和生产行为以及最终影响程度。并进一步比较影响我国工业企业低碳生产意愿和生产行为的主要因素间的异同。研究发现,除了企业注册类型,其他各主要因素均显著影响我国工业企业的低碳生产意愿;而对企业低碳生产行为的主要影响因素的分析发现,仅企业管理者特征、企业规模和技术能力特征显著影响我国工业企业的低碳生产行为。据此结果,提出不断加大我国工业企业的自主技术创新能力,以及政府适度引导规模以上工业企业实施节能减排等相关政策建议。 展开更多
关键词 工业企业 低碳生产意愿与行为 罚函数的Logistic回归模型 INTERVAL Censored回归模型
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我国食品工业可追溯体系构建的意愿与水平研究 被引量:4
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作者 山丽杰 徐玲玲 王晓莉 《河南社会科学》 CSSCI 北大核心 2015年第7期77-84,124,共8页
在目前食品安全事件频发的背景之下,以我国88家不同类型的食品生产企业为案例,采用带罚函数的二元Logistic回归模型与Interval Censored回归的组合方法,分别研究与比较了食品生产企业对可追溯体系的投资意愿与投资水平的主要影响因素。... 在目前食品安全事件频发的背景之下,以我国88家不同类型的食品生产企业为案例,采用带罚函数的二元Logistic回归模型与Interval Censored回归的组合方法,分别研究与比较了食品生产企业对可追溯体系的投资意愿与投资水平的主要影响因素。研究结果表明,影响食品生产企业可追溯体系投资意愿的主要因素是企业管理者的年龄和受教育程度、销售规模、质量认证、预期收益、政府政策优惠情况,而影响企业投资水平的主要因素是行业特征、企业的销售规模、投资的预期收益和政府的优惠政策。 展开更多
关键词 食品可追溯体系 投资意愿 投资水平 带罚函数的二元Logistic回归模型 INTERVAL Censored回归模型
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中国能源效率测度及其影响因素分析 被引量:12
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作者 周睿 《统计与决策》 CSSCI 北大核心 2014年第5期84-86,共3页
文章通过DEA-Censored Data模型分析框架,利用CCR模型和BCC模型分别测度了改革开放后中国近30年来的中国能源效率,并分析了诸如能源结构、所有制结构、产业结构等因素对其的影响。
关键词 能源效率 CCR模型 BCC模型 Censored DATA模型
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通勤者非工作活动选择行为研究 被引量:2
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作者 鲜于建川 隽志才 《交通运输系统工程与信息》 EI CSCD 北大核心 2014年第2期220-225,共6页
早晚高峰时段非工作出行需求的增加,加剧了城市交通拥堵.本文采用基于活动的方法分析了通勤者非工作活动选择行为.研究以某直辖市居民出行调查数据为基础,将非工作活动发生时段数据作为截取样本,建立了通勤者非工作活动参与及活动时段... 早晚高峰时段非工作出行需求的增加,加剧了城市交通拥堵.本文采用基于活动的方法分析了通勤者非工作活动选择行为.研究以某直辖市居民出行调查数据为基础,将非工作活动发生时段数据作为截取样本,建立了通勤者非工作活动参与及活动时段安排的Censored Probit模型.从通勤者是否选择非工作活动和是否将非工作活动安排在上下班途中两个方面,讨论了通勤者非工作活动安排与通勤者及其家庭社会经济属性、非工作活动和通勤出行特征之间的关系.研究表明,出行者社会经济属性、交通系统属性、工作安排和通勤出行方式都是重要影响因素,所建立的模型能有效分析上述因素的变化对通勤者非工作活动选择行为的影响.本研究对交通需求预测和管理工作有重要意义. 展开更多
关键词 系统工程 Censored PROBIT模型 非工作活动选择 通勤者 通勤出行 基于活动的方法
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Statistical analysis of generalized exponential distribution under progressive censoring with binomial removals 被引量:11
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作者 Weian Yan Yimin Shi +1 位作者 Baowei Song Zhaoyong Mao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第4期707-714,共8页
The estimation of generalized exponential distribution based on progressive censoring with binomial removals is presented, where the number of units removed at each failure time follows a binomial distribution. Maximu... The estimation of generalized exponential distribution based on progressive censoring with binomial removals is presented, where the number of units removed at each failure time follows a binomial distribution. Maximum likelihood estimators of the parameters and their confidence intervals are derived. The expected time required to complete the life test under this censoring scheme is investigated. Finally, the numerical examples are given to illustrate some theoretical results by means of Monte-Carlo simulation. 展开更多
关键词 binomial removal progressive censoring maximumlikelihood estimator expected experiment time generalized exponential distribution.
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CONSISTENCY OF MLE OF THE PARAMETER OF EXPONENTIAL LIFETIME DISTRIBUTION FOR RANDOM CENSORING MODEL WITH INCOMPLETE INFORMATION 被引量:18
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作者 YE ERHUA 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1995年第4期379-386,共8页
In this paper, we have discussed a random censoring test with incomplete information, and proved that the maximum likelihood estimator(MLE) of the parameter based on the randomly censored data with incomplete informat... In this paper, we have discussed a random censoring test with incomplete information, and proved that the maximum likelihood estimator(MLE) of the parameter based on the randomly censored data with incomplete information in the case of the exponential distribution has the strong consistency. 展开更多
关键词 Random censoring test with incomplete information exponential distribution maximum likelihood estimator consistency.
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企业实施食品可追溯体系的投资意愿与投入水平研究 被引量:20
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作者 山丽杰 吴林海 徐玲玲 《华南农业大学学报(社会科学版)》 CSSCI 2011年第4期85-92,共8页
基于Logistic、Interval Censored回归模型,研究了影响食品生产企业实施可追溯体系的投资意愿与投资水平的主要因素。结果表明,79.2%的企业愿意投资实施可追溯体系,其中80.7%的企业选择的投资水平在新增投资的20%及以下。影响企业实施... 基于Logistic、Interval Censored回归模型,研究了影响食品生产企业实施可追溯体系的投资意愿与投资水平的主要因素。结果表明,79.2%的企业愿意投资实施可追溯体系,其中80.7%的企业选择的投资水平在新增投资的20%及以下。影响企业实施可追溯体系投资意愿的主要因素是企业从业人数(1000-2000人之间)、管理者年龄、预期收益和政府优惠政策,而影响投资水平的主要因素是农副产品加工业的行业特征、销售规模(3亿元及以上)、管理者学历层次(大专及以上)和预期收益。 展开更多
关键词 食品可追溯体系 食品生产企业 投资意愿 投资水平 INTERVAL Censored回归模型
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Statistical Analysis for the Birnbaum-Saunders Fatigue Life Distribution under Type-Ⅱ Bilateral Censoring and Multiply Type-II Censoring 被引量:12
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作者 WANGRong-hua FEIHe-liang 《Chinese Quarterly Journal of Mathematics》 CSCD 2004年第2期126-132,共7页
In present paper, we obtain the inverse moment estimations of parameters of the Birnbaum-Saunders fatigue life distribution based on Type-Ⅱ bilateral censored samples and multiply Type-Ⅱ censored sample. In this pap... In present paper, we obtain the inverse moment estimations of parameters of the Birnbaum-Saunders fatigue life distribution based on Type-Ⅱ bilateral censored samples and multiply Type-Ⅱ censored sample. In this paper, we also get the interval estimations of the scale parameters. 展开更多
关键词 Birnbaum-Saunders fatigue life distribution Type-Ⅱ bilateral censoring missing data inverse moment estimation interval estimation
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The dynamic impact of income and income distribution on food consumption among adults in rural China 被引量:5
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作者 LI Lei ZHAI Shi-xian BAI Jun-fei 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2021年第1期330-342,I0001,I0002,共15页
Previous studies have demonstrated that income has a significant effect on food demand in rural China. However, little research has focused on the dynamic impact of income and income distribution on food demand in rur... Previous studies have demonstrated that income has a significant effect on food demand in rural China. However, little research has focused on the dynamic impact of income and income distribution on food demand in rural China. Using China Health and Nutrition Survey data, this study employs a consistent two-step quadratic almost ideal demand system model, with addressed problems of endogeneity of total expenditure and zero shares, to estimate the food demand elasticities among adults in rural areas with regard to the different income strata. The results show that changes in income and income strata have significant effects on food demand in rural areas. Except for grains, all other food groups, including vegetables, oils and fats, animal products, and other foods, have positive income elasticities, and the rise in the income strata will lead to declining income elasticities for grains, vegetables, oils and fats, and animal products. Based on the estimated income elasticities, the food consumption projections indicate that reducing income inequality in rural society can improve the living standard of low-income people in terms of nutrient intakes. 展开更多
关键词 income redistribution food demand ENDOGENEITY censored demand system rural China
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SAMPLING INSPECTION OF RELIABILITY IN (LOG)NORMAL CASE WITH TYPE I CENSORING 被引量:4
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作者 吴启光 吕建华 《Acta Mathematica Scientia》 SCIE CSCD 2006年第2期331-343,共13页
This article proposes a statistical method for working out reliability sampling plans under Type I censored sample for items whose failure times have either normal or lognormal distributions. The quality statistic is ... This article proposes a statistical method for working out reliability sampling plans under Type I censored sample for items whose failure times have either normal or lognormal distributions. The quality statistic is a method of moments estimator of a monotonous function of the unreliability. An approach of choosing a truncation time is recommended. The sample size and acceptability constant are approximately determined by using the Cornish-Fisher expansion for quantiles of distribution. Simulation results show that the method given in this article is feasible. 展开更多
关键词 Type I censoring lognormal distribution normal distribution reliability sampling plans
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