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Low-Carbon Dispatch of an Integrated Energy System Considering Confidence Intervals for Renewable Energy Generation
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作者 Yan Shi Wenjie Li +2 位作者 Gongbo Fan Luxi Zhang Fengjiu Yang 《Energy Engineering》 EI 2024年第2期461-482,共22页
Addressing the insufficiency in down-regulation leeway within integrated energy systems stemming from the erratic and volatile nature of wind and solar renewable energy generation,this study focuses on formulating a c... Addressing the insufficiency in down-regulation leeway within integrated energy systems stemming from the erratic and volatile nature of wind and solar renewable energy generation,this study focuses on formulating a coordinated strategy involving the carbon capture unit of the integrated energy system and the resources on the load storage side.A scheduling model is devised that takes into account the confidence interval associated with renewable energy generation,with the overarching goal of optimizing the system for low-carbon operation.To begin with,an in-depth analysis is conducted on the temporal energy-shifting attributes and the low-carbon modulation mechanisms exhibited by the source-side carbon capture power plant within the context of integrated and adaptable operational paradigms.Drawing from this analysis,a model is devised to represent the adjustable resources on the charge-storage side,predicated on the principles of electro-thermal coupling within the energy system.Subsequently,the dissimilarities in the confidence intervals of renewable energy generation are considered,leading to the proposition of a flexible upper threshold for the confidence interval.Building on this,a low-carbon dispatch model is established for the integrated energy system,factoring in the margin allowed by the adjustable resources.In the final phase,a simulation is performed on a regional electric heating integrated energy system.This simulation seeks to assess the impact of source-load-storage coordination on the system’s low-carbon operation across various scenarios of reduction margin reserves.The findings underscore that the proactive scheduling model incorporating confidence interval considerations for reduction margin reserves effectively mitigates the uncertainties tied to renewable energy generation.Through harmonized orchestration of source,load,and storage elements,it expands the utilization scope for renewable energy,safeguards the economic efficiency of system operations under low-carbon emission conditions,and empirically validates the soundness and efficacy of the proposed approach. 展开更多
关键词 Integrated energy system carbon capture power plant confidence interval optimized scheduling
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Assessing healthcare workers’knowledge and confidence in the diagnosis,management and prevention of Monkeypox
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作者 Epipode Ntawuyamara Thierry Ingabire +3 位作者 Innocent Yandemye Polycarpe Ndayikeza Bina Bhandari Yan-Hua Liang 《World Journal of Clinical Cases》 SCIE 2025年第1期38-47,共10页
BACKGROUND Monkeypox(Mpox),is a disease of global public health concern,as it does not affect only countries in western and central Africa.AIM To assess Burundi healthcare workers(HCWs)s’level of knowledge and confid... BACKGROUND Monkeypox(Mpox),is a disease of global public health concern,as it does not affect only countries in western and central Africa.AIM To assess Burundi healthcare workers(HCWs)s’level of knowledge and confidence in the diagnosis and management of Mpox.METHODS We conducted a cross-sectional study via an online survey designed mainly from the World Health Organization course distributed among Burundi HCWs from June-July 2023.The questionnaire comprises 8 socioprofessional-related questions,22 questions about Mpox disease knowledge,and 3 questions to assess confidence in Mpox diagnosis and management.The data were analyzed via SPSS software version 25.0.A P value<0.05 was considered to indicate statistical significance.RESULTS The study sample comprised 471 HCWs who were mainly medical doctors(63.9%)and nurses(30.1%).None of the 22 questions concerning Mpox knowledge had at least 50%correct responses.A very low number of HCWs(17.4%)knew that Mpox has a vaccine.The confidence level to diagnose(21.20%),treat(18.00%)or prevent(23.30%)Mpox was low among HCWs.The confidence level in the diagnosis of Mpox was associated with the HCWs’age(P value=0.009),sex(P value<0.001),work experience(P value=0.002),and residence(P value<0.001).The confidence level to treat Mpox was significantly associated with the HCWs’age(P value=0.050),sex(P value<0.001),education(P value=0.033)and occupation(P value=0.005).The confidence level to prevent Mpox was associated with the HCWs’education(P value<0.001),work experience(P value=0.002),residence(P value<0.001)and type of work institution(P value=0.003).CONCLUSION This study revealed that HCWs have the lowest level of knowledge regarding Mpox and a lack of confidence in the ability to diagnose,treat or prevent it.There is an urgent need to organize continuing medical education programs on Mpox epidemiology and preparedness for Burundi HCWs.We encourage future researchers to assess potential hesitancy toward Mpox vaccination and its associated factors. 展开更多
关键词 MONKEYPOX Public health emergency of international concern Healthcare workers EPIDEMIC PREPAREDNESS KNOWLEDGE confidence
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The burden of upper motor neuron involvement is correlated with the bilateral limb involvement interval in patients with amyotrophic lateral sclerosis:a retrospective observational study
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作者 Jieying Wu Shan Ye +2 位作者 Xiangyi Liu Yingsheng Xu Dongsheng Fan 《Neural Regeneration Research》 SCIE CAS 2025年第5期1505-1512,共8页
Amyotrophic lateral sclerosis is a rare neurodegenerative disease characterized by the involvement of both upper and lower motor neurons.Early bilateral limb involvement significantly affects patients'daily lives ... Amyotrophic lateral sclerosis is a rare neurodegenerative disease characterized by the involvement of both upper and lower motor neurons.Early bilateral limb involvement significantly affects patients'daily lives and may lead them to be confined to bed.However,the effect of upper and lower motor neuron impairment and other risk factors on bilateral limb involvement is unclear.To address this issue,we retrospectively collected data from 586 amyotrophic lateral sclerosis patients with limb onset diagnosed at Peking University Third Hospital between January 2020 and May 2022.A univariate analysis revealed no significant differences in the time intervals of spread in different directions between individuals with upper motor neuron-dominant amyotrophic lateral sclerosis and those with classic amyotrophic lateral sclerosis.We used causal directed acyclic graphs for risk factor determination and Cox proportional hazards models to investigate the association between the duration of bilateral limb involvement and clinical baseline characteristics in amyotrophic lateral sclerosis patients.Multiple factor analyses revealed that higher upper motor neuron scores(hazard ratio[HR]=1.05,95%confidence interval[CI]=1.01–1.09,P=0.018),onset in the left limb(HR=0.72,95%CI=0.58–0.89,P=0.002),and a horizontal pattern of progression(HR=0.46,95%CI=0.37–0.58,P<0.001)were risk factors for a shorter interval until bilateral limb involvement.The results demonstrated that a greater degree of upper motor neuron involvement might cause contralateral limb involvement to progress more quickly in limb-onset amyotrophic lateral sclerosis patients.These findings may improve the management of amyotrophic lateral sclerosis patients with limb onset and the prediction of patient prognosis. 展开更多
关键词 amyotrophic lateral sclerosis bilateral limb involvement Cox proportional hazards regression model horizontal spread restricted cubic spline analysis time interval upper motor neuron vertical spread
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Time-varying confidence interval forecasting of travel time for urban arterials using ARIMA-GARCH model 被引量:6
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作者 崔青华 夏井新 《Journal of Southeast University(English Edition)》 EI CAS 2014年第3期358-362,共5页
To improve the forecasting reliability of travel time, the time-varying confidence interval of travel time on arterials is forecasted using an autoregressive integrated moving average and generalized autoregressive co... To improve the forecasting reliability of travel time, the time-varying confidence interval of travel time on arterials is forecasted using an autoregressive integrated moving average and generalized autoregressive conditional heteroskedasticity (ARIMA-GARCH) model. In which, the ARIMA model is used as the mean equation of the GARCH model to model the travel time levels and the GARCH model is used to model the conditional variances of travel time. The proposed method is validated and evaluated using actual traffic flow data collected from the traffic monitoring system of Kunshan city. The evaluation results show that, compared with the conventional ARIMA model, the proposed model cannot significantly improve the forecasting performance of travel time levels but has advantage in travel time volatility forecasting. The proposed model can well capture the travel time heteroskedasticity and forecast the time-varying confidence intervals of travel time which can better reflect the volatility of observed travel times than the fixed confidence interval provided by the ARIMA model. 展开更多
关键词 confidence interval forecasting travel time autoregressive integrated moving average and generalized autoregressive conditional heteroskedasticity ARIMA-GARCH) conditional variance reliability
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Deep learning-based evaluation of factor of safety with confidence interval for tunnel deformation in spatially variable soil 被引量:8
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作者 Jinzhang Zhang Kok Kwang Phoon +2 位作者 Dongming Zhang Hongwei Huang Chong Tang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2021年第6期1358-1367,共10页
The random finite difference method(RFDM) is a popular approach to quantitatively evaluate the influence of inherent spatial variability of soil on the deformation of embedded tunnels.However,the high computational co... The random finite difference method(RFDM) is a popular approach to quantitatively evaluate the influence of inherent spatial variability of soil on the deformation of embedded tunnels.However,the high computational cost is an ongoing challenge for its application in complex scenarios.To address this limitation,a deep learning-based method for efficient prediction of tunnel deformation in spatially variable soil is proposed.The proposed method uses one-dimensional convolutional neural network(CNN) to identify the pattern between random field input and factor of safety of tunnel deformation output.The mean squared error and correlation coefficient of the CNN model applied to the newly untrained dataset was less than 0.02 and larger than 0.96,respectively.It means that the trained CNN model can replace RFDM analysis for Monte Carlo simulations with a small but sufficient number of random field samples(about 40 samples for each case in this study).It is well known that the machine learning or deep learning model has a common limitation that the confidence of predicted result is unknown and only a deterministic outcome is given.This calls for an approach to gauge the model’s confidence interval.It is achieved by applying dropout to all layers of the original model to retrain the model and using the dropout technique when performing inference.The excellent agreement between the CNN model prediction and the RFDM calculated results demonstrated that the proposed deep learning-based method has potential for tunnel performance analysis in spatially variable soils. 展开更多
关键词 Deep learning Convolutional neural network(CNN) Tunnel safety confidence interval Random field
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Statistical damage detection method for frame structures using a confidence interval 被引量:2
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作者 Li Weiming,Zhu Hongping~(++),Luo Hanbin~(++) and Xia Yong~(++) School of Civil Engineering and Mechanics,Huazhong University of Science and Technology,Wuhan 430074,China ~+PhD Candidate ++ Professor 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2010年第1期133-140,共8页
A novel damage detection method is applied to a 3-story frame structure, to obtain statistical quantification control criterion of the existence, location and identification of damage. The mean, standard deviation, an... A novel damage detection method is applied to a 3-story frame structure, to obtain statistical quantification control criterion of the existence, location and identification of damage. The mean, standard deviation, and exponentially weighted moving average (EWMA) are applied to detect damage information according to statistical process control (SPC) theory. It is concluded that the detection is insignificant with the mean and EWMA because the structural response is not independent and is not a normal distribution. On the other hand, the damage information is detected well with the standard deviation because the influence of the data distribution is not pronounced with this parameter. A suitable moderate confidence level is explored for more significant damage location and quantification detection, and the impact of noise is investigated to illustrate the robustness of the method. 展开更多
关键词 damage detection standard deviation statistical method confidence interval noise
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Rules for confidence intervals of permeability coefficients for water flow in over-broken rock mass 被引量:7
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作者 Liu Weiqun Fei Xiaodong Fang Jingnian 《International Journal of Mining Science and Technology》 2012年第1期29-33,共5页
Based on the steady-state seepage method, we used the Mechanical Testing and Simulation 815.02 System and a self-designed seepage instrument for over-broken stone to measure seepage properties of water flows in three ... Based on the steady-state seepage method, we used the Mechanical Testing and Simulation 815.02 System and a self-designed seepage instrument for over-broken stone to measure seepage properties of water flows in three types of crushed rock samples. Three methods of confidence interval in describing permeability coefficients are presented: the secure interval, the calculated interval and the systemic interval. The lower bound of the secure interval can be applied to water-inrush and the upper bound can solve the problem of connectivity. For the calculated interval, as the axial pressure increases, the length of confidence interval is shortened and the upper and lower bounds are reduced. For the systemic interval, the length of its confidence interval, as well as the upper and lower bounds, clearly vary under low axial pressure but are fairly similar under high axial pressure. These three methods provide useful information and references for analyzing the permeability coefficient of over-broken rock. 展开更多
关键词 Over-broken rock mass Permeability coefficient Secure interval Calculated interval Systemic interval
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Moved Score Confidence Intervals for Means of Discrete Distributions 被引量:1
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作者 Yu Guan 《Open Journal of Statistics》 2011年第2期81-86,共6页
Let X denote a discrete distribution as Poisson, binomial or negative binomial variable. The score confidence interval for the mean of X is obtained based on inverting the hypothesis test and the central limit theorem... Let X denote a discrete distribution as Poisson, binomial or negative binomial variable. The score confidence interval for the mean of X is obtained based on inverting the hypothesis test and the central limit theorem is discussed and recommended widely. But it has sharp downward spikes for small means. This paper proposes to move the score interval left a little (about 0.04 unit), called by moved score confidence interval. Numerical computation and Edgeworth expansion show that the moved score interval is analogous to the score interval completely and behaves better for moderate means;for small means the moved interval raises the infimum of the coverage probability and improves the sharp spikes significantly. Especially, it has unified explicit formulations to compute easily. 展开更多
关键词 confidence interval confidence Level COVERAGE PROBABILITY DISCRETE Distribution Moved SCORE confidence interval
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Bootstrap Confidence Intervals for Proportions of Unequal Sized Groups Adjusted for Overdispersion 被引量:1
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作者 Olivia Wanjeri Mwangi Ali Islam Orawo Luke 《Open Journal of Statistics》 2015年第6期502-510,共9页
Group testing is a method of pooling a number of units together and performing a single test on the resulting group. It is an appealing option when few individual units are thought to be infected leading to reduced co... Group testing is a method of pooling a number of units together and performing a single test on the resulting group. It is an appealing option when few individual units are thought to be infected leading to reduced costs of testing as compared to individually testing the units. Group testing aims to identify the positive groups in all the groups tested or to estimate the proportion of positives (p) in a population. Interval estimation methods of the proportions in group testing for unequal group sizes adjusted for overdispersion have been examined. Lately improvement in statistical methods allows the construction of highly accurate confidence intervals (CIs). The aim here is to apply group testing for estimation and generate highly accurate Bootstrap confidence intervals (CIs) for the proportion of defective or positive units in particular. This study provided a comparison of several proven methods of constructing CIs for a binomial proportion after adjusting for overdispersion in group testing with groups of unequal sizes. Bootstrap resampling was applied on data simulated from binomial distribution, and confidence intervals with high coverage probabilities were produced. This data was assumed to be overdispersed and independent between groups but correlated within these groups. Interval estimation methods based on the Wald, the Logit and Complementary log-log (CLL) functions were considered. The criterion used in the comparisons is mainly the coverage probabilities attained by nominal 95% CIs, though interval width is also regarded. Bootstrapping produced CIs with high coverage probabilities for each of the three interval methods. 展开更多
关键词 Group Testing Overdispersion QUASI-LIKELIHOOD confidence interval BOOTSTRAPPING COVERAGE Probability
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Stepwise Confidence Interval Method for MTD Studies with Binomial Populations 被引量:1
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作者 Na Yu Xiaoqing Tang Hanxing Wang 《Engineering(科研)》 2013年第10期463-466,共4页
Now we extend one method into a sequence of binomial data, propose a stepwise confidence interval method for toxic-ity study, and also in our paper, two methods of constructing intervals for the risk difference are pr... Now we extend one method into a sequence of binomial data, propose a stepwise confidence interval method for toxic-ity study, and also in our paper, two methods of constructing intervals for the risk difference are proposed. The first one is based on the well-known conditional confidence intervals for odds ratio, and the other one comes from Santner“small-sample confidence intervals for the difference of two success probabilities”, and it produces exact intervals, through employing our method. 展开更多
关键词 STEPWISE confidence interval Practical EQUIVALENCE Maximum Tolerated Dose
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Confidence Intervals for Relative Intensity of Collaboration(RIC)Indicators
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作者 Joel Emanuel Fuchs Lawrence Smolinsky Ronald Rousseau 《Journal of Data and Information Science》 CSCD 2022年第4期5-15,共11页
Purpose:We aim to extend our investigations related to the Relative Intensity of Collaboration(RIC)indicator,by constructing a confidence interval for the obtained values.Design/methodology/approach:We use Mantel-Haen... Purpose:We aim to extend our investigations related to the Relative Intensity of Collaboration(RIC)indicator,by constructing a confidence interval for the obtained values.Design/methodology/approach:We use Mantel-Haenszel statistics as applied recently by Smolinsky,Klingenberg,and Marx.Findings:We obtain confidence intervals for the RIC indicatorResearch limitations:It is not obvious that data obtained from the Web of Science(or any other database)can be considered a random sample.Practical implications:We explain how to calculate confidence intervals.Bibliometric indicators are more often than not presented as precise values instead of an approximation depending on the database and the time of measurement.Our approach presents a suggestion to solve this problem.Originality/value:Our approach combines the statistics of binary categorical data and bibliometric studies of collaboration. 展开更多
关键词 Contingency tables confidence intervals Relative intensity of collaboration(RIC) Mantel-Haenszel statistics Science of science
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Semi-empiricial Likelihood Confidence Intervals for the Differences of Two Populations Based on Fractional Imputation
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作者 BAI YUN-XIA QIN YONG-SONG +1 位作者 WANG LI-RONG LI LING 《Communications in Mathematical Research》 CSCD 2009年第2期123-136,共14页
Suppose that there are two populations x and y with missing data on both of them, where x has a distribution function F(·) which is unknown and y has a distribution function Gθ(·) with a probability den... Suppose that there are two populations x and y with missing data on both of them, where x has a distribution function F(·) which is unknown and y has a distribution function Gθ(·) with a probability density function gθ(·) with known form depending on some unknown parameter θ. Fractional imputation is used to fill in missing data. The asymptotic distributions of the semi-empirical likelihood ration statistic are obtained under some mild conditions. Then, empirical likelihood confidence intervals on the differences of x and y are constructed. 展开更多
关键词 empirical likelihood confidence intervals fractional imputation missingdata
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A MICROCOMPUTER PROGRAM FOR CALCULATINGTHE CONFIDENCE INTERVALS OF SURVIVAL PROBABILITY IN MEDICAL FOLLOW-UP STUDIES
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作者 项永兵 高玉堂 金凡 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 1996年第1期72-78,共7页
In cancer survival analysis, it is very frequently to estimate the confidence intervals for survival probabilities.But this calculation is not commonly involve in most popular computer packages, or only one methods of... In cancer survival analysis, it is very frequently to estimate the confidence intervals for survival probabilities.But this calculation is not commonly involve in most popular computer packages, or only one methods of estimation in the packages. In the present Paper, we will describe a microcomputer Program for estimating the confidence intervals of survival probabilities, when the survival functions are estimated using Kaplan-Meier product-limit or life-table method. There are five methods of estimation in the program (SPCI), which are the classical(based on Greenwood's formula of variance of S(ti), Rothman-Wilson, arcsin transformation, log(-Iog) transformation, Iogit transformation methods. Two example analysis are given for testing the performances of the program running. 展开更多
关键词 Survival analysis confidence intervals Kaplan-Meier estimator Life-table estimator Microcomputer BASIC.
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Confidence Interval Estimation of the Correlation in the Presence of Non-Detects
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作者 Courtney E. McCracken Stephen W. Looney 《Open Journal of Statistics》 2021年第3期463-475,共13页
This article deals with correlating two variables that have values that fall below the known limit of detection (LOD) of the measuring device;these values are known as non-detects (NDs). We use simulation to compare s... This article deals with correlating two variables that have values that fall below the known limit of detection (LOD) of the measuring device;these values are known as non-detects (NDs). We use simulation to compare several methods for estimating the association between two such variables. The most commonly used method, simple substitution, consists of replacing each ND with some representative value such as LOD/2. Spearman’s correlation, in which all NDs are assumed to be tied at some value just smaller than the LOD, is also used. We evaluate each method under several scenarios, including small to moderate sample size, moderate to large censoring proportions, extr</span><span style="font-family:Verdana;">eme imbalance in censoring proportions, and non-bivariate nor</span><span style="font-family:Verdana;">mal (BVN) data. In this article, we focus on the coverage probability of 95% confidence intervals obtained using each method. Confidence intervals using a maximum likelihood approach based on the assumption of BVN data have acceptable performance under most scenarios, even with non-BVN data. Intervals based on Spearman’s coefficient also perform well under many conditions. The methods are illustrated using real data taken from the biomarker literature. 展开更多
关键词 confidence interval Coverage Probability Left Censoring Limit of Detection Maximum Likelihood Spearman Correlation
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Computing Confidence Intervals for the Postal Service’s Cost-Elasticity Estimates
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作者 Bzhilyanskaya Y. Lyudmila Margaret M. Cigno Soiliou D. Namoro 《Open Journal of Statistics》 2021年第5期607-619,共13页
This paper provides methods for assessing the precision of cost elasticity estimates when the underlying regression function is assumed to be polynomial. Specifically, the paper adapts two well-known methods for compu... This paper provides methods for assessing the precision of cost elasticity estimates when the underlying regression function is assumed to be polynomial. Specifically, the paper adapts two well-known methods for computing confidential intervals for ratios: the delta-method and the Fieller method. We show that performing the estimation with mean-centered explanatory variables provides a straightforward way to estimate the elasticity and compute a confidence interval for it. A theoretical discussion of the proposed methods is provided, as well as an empirical example based on publicly available postal data. Possible areas of application include postal service providers worldwide, transportation and electricity. 展开更多
关键词 Volume Variability confidence interval Ratio Parameter Delta Method Fieller Method
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Confidence Intervals for the Binomial Proportion: A Comparison of Four Methods
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作者 Luke Akong’o Orawo 《Open Journal of Statistics》 2021年第5期806-816,共11页
This paper presents four methods of constructing the confidence interval for the proportion <i><span style="font-family:Verdana;">p</span></i><span style="font-family:;" ... This paper presents four methods of constructing the confidence interval for the proportion <i><span style="font-family:Verdana;">p</span></i><span style="font-family:;" "=""><span style="font-family:Verdana;"> of the binomial distribution. Evidence in the literature indicates the standard Wald confidence interval for the binomial proportion is inaccurate, especially for extreme values of </span><i><span style="font-family:Verdana;">p</span></i><span style="font-family:Verdana;">. Even for moderately large sample sizes, the coverage probabilities of the Wald confidence interval prove to be erratic for extreme values of </span><i><span style="font-family:Verdana;">p</span></i><span style="font-family:Verdana;">. Three alternative confidence intervals, namely, Wilson confidence interval, Clopper-Pearson interval, and likelihood interval</span></span><span style="font-family:Verdana;">,</span><span style="font-family:Verdana;"> are compared to the Wald confidence interval on the basis of coverage probability and expected length by means of simulation.</span> 展开更多
关键词 Binomial Distribution confidence interval Coverage Probability Expected Length Relative Likelihood Function
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Approximate Confidence Interval for the Mean of Poisson Distribution
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作者 Manad Khamkong 《Open Journal of Statistics》 2012年第2期204-207,共4页
A Poisson distribution is well used as a standard model for analyzing count data. Most of the usual constructing confidence intervals are based on an asymptotic approximation to the distribution of the sample mean by ... A Poisson distribution is well used as a standard model for analyzing count data. Most of the usual constructing confidence intervals are based on an asymptotic approximation to the distribution of the sample mean by using the Wald interval. That is, the Wald interval has poor performance in terms of coverage probabilities and average widths interval for small means and small to moderate sample sizes. In this paper, an approximate confidence interval for a Poisson mean is proposed and is based on an empirically determined the tail probabilities. Simulation results show that the pro- posed interval outperforms the others when small means and small to moderate sample sizes. 展开更多
关键词 confidence interval COVERAGE Probability POISSON Distribution EXPECTED Width Wald interval
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Algorithms of Confidence Intervals of WG Distribution Based on Progressive Type-II Censoring Samples
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作者 Mohamed A. El-Sayed Fathy H. Riad +1 位作者 M. A. Elsafty Yarub A. Estaitia 《Journal of Computer and Communications》 2017年第7期101-116,共16页
The purpose of this article offers different algorithms of Weibull Geometric (WG) distribution estimation depending on the progressive Type II censoring samples plan, spatially the joint confidence intervals for the p... The purpose of this article offers different algorithms of Weibull Geometric (WG) distribution estimation depending on the progressive Type II censoring samples plan, spatially the joint confidence intervals for the parameters. The approximate joint confidence intervals for the parameters, the approximate confidence regions and percentile bootstrap intervals of confidence are discussed, and several Markov chain Monte Carlo (MCMC) techniques are also presented. The parts of mean square error (MSEs) and credible intervals lengths, the estimators of Bayes depend on non-informative implement more effective than the maximum likelihood estimates (MLEs) and bootstrap. Comparing the models, the MSEs, average confidence interval lengths of the MLEs, and Bayes estimators for parameters are less significant for censored models. 展开更多
关键词 ALGORITHMS Simulations Point Estimation confidence intervalS Bootstrap Approximate BAYES ESTIMATORS MCMC MLEs
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DEA Scores’ Confidence Intervals with Past-Present and Past-Present-Future Based Resampling
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作者 Kaoru Tone Jamal Ouenniche 《American Journal of Operations Research》 2016年第2期121-135,共15页
In data envelopment analysis (DEA), input and output values are subject to change for several reasons. Such variations differ in their input/output items and their decision-making units (DMUs). Hence, DEA efficiency s... In data envelopment analysis (DEA), input and output values are subject to change for several reasons. Such variations differ in their input/output items and their decision-making units (DMUs). Hence, DEA efficiency scores need to be examined by considering these factors. In this paper, we propose new resampling models based on these variations for gauging the confidence intervals of DEA scores. The first model utilizes past-present data for estimating data variations imposing chronological order weights which are supplied by Lucas series (a variant of Fibonacci series). The second model deals with future prospects. This model aims at forecasting the future efficiency score and its confidence interval for each DMU. We applied our models to a dataset composed of Japanese municipal hospitals. 展开更多
关键词 Data Variation RESAMPLING confidence interval Past-Present-Future DEA Hospital
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Orthostatic Hypotension: QTc Interval Prolongation during Head-Up Tilt
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作者 Gabriel Vanerio Maria Jose Arocena 《International Journal of Clinical Medicine》 CAS 2024年第9期443-455,共13页
Background: The QT interval shortens in response to sympathetic stimulation. Head-up tilt-table (HUT) testing is a straightforward way to achieve brisk sympathetic stimulation. There is not enough information about th... Background: The QT interval shortens in response to sympathetic stimulation. Head-up tilt-table (HUT) testing is a straightforward way to achieve brisk sympathetic stimulation. There is not enough information about the response of the QT interval to HUT, particularly, in patients with orthostatic hypotension (OH). Objective: Analyse the response of the RR, QT and QTc intervals in patients with OH and reflex syncope (NM) during HUT and find differences between groups. Methods: We reviewed the electrocardiograms and compare the RR and QT/QTc intervals during 1) baseline;2) HUT plus hyperventilation;3) positive test. Results: We studied 137 patients, 62 control group (no syncope and negative HUT). On average, the RR HUT interval was shorter than the resting RR by −171 ± 110.4 ms in controls;−228.6 ± 119.4 ms (NM) and −194 ± (OH) (P Conclusion: Significant differences between the reflex group and the OH during a positive test, the QTc decreased in the NM group, but in the OH population increased. This observation has not been described. We hypothesize that QTc prolongation could reflect autonomic nervous system downregulation and could explain to a degree, the increased mortality in this group. 展开更多
关键词 SYNCOPE Orthostatic Hypotension QTc interval Reflex Syncope Autonomic Nervous System
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