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Teaching Reform and Practice of Statistics Courses in Big Data Management and Applications Major in the Context of New Quality Productivity
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作者 Tinghui Huang Junchao Dong Liang Min 《Journal of Contemporary Educational Research》 2025年第2期23-31,共9页
In the new era,the impact of emerging productive forces has permeated every sector of industry.As the core production factor of these forces,data plays a pivotal role in industrial transformation and social developmen... In the new era,the impact of emerging productive forces has permeated every sector of industry.As the core production factor of these forces,data plays a pivotal role in industrial transformation and social development.Consequently,many domestic universities have introduced majors or courses related to big data.Among these,the Big Data Management and Applications major stands out for its interdisciplinary approach and emphasis on practical skills.However,as an emerging field,it has not yet accumulated a robust foundation in teaching theory and practice.Current instructional practices face issues such as unclear training objectives,inconsistent teaching methods and course content,insufficient integration of practical components,and a shortage of qualified faculty-factors that hinder both the development of the major and the overall quality of education.Taking the statistics course within the Big Data Management and Applications major as an example,this paper examines the challenges faced by statistics education in the context of emerging productive forces and proposes corresponding improvement measures.By introducing innovative teaching concepts and strategies,the teaching system for professional courses is optimized,and authentic classroom scenarios are recreated through illustrative examples.Questionnaire surveys and statistical analyses of data collected before and after the teaching reforms indicate that the curriculum changes effectively enhance instructional outcomes,promote the development of the major,and improve the quality of talent cultivation. 展开更多
关键词 New quality productivity Big data Compound talents statistics course Teaching examples
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Exploration on the Ideological and Political Construction Path of the“Probability Theory and Mathematical Statistics”Course
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作者 Qianlong Dang Xiaofeng Yang Wenliang Wu 《Journal of Contemporary Educational Research》 2025年第10期85-91,共7页
This paper focuses on the ideological and political construction of the course“Probability Theory and Mathematical Statistics.”Aiming at the current situation in teaching where emphasis is placed on knowledge impart... This paper focuses on the ideological and political construction of the course“Probability Theory and Mathematical Statistics.”Aiming at the current situation in teaching where emphasis is placed on knowledge imparting while value guidance is neglected,and combined with the requirements of ideological and political education policies in the new era,this paper explores the integration path between professional courses and ideological and political education.Through literature analysis,case comparison,and empirical research,the study proposes a systematic implementation plan covering the design of teaching objectives,the reconstruction of teaching content,and the optimization of the evaluation system.The purpose is to cultivate students’sense of social responsibility and innovative awareness by excavating the ideological and political elements in mathematics.The research results provide practical reference for colleges and universities to deepen the reform of ideological and political education in courses,and promote the implementation of the fundamental task of fostering virtue through education in STEM education. 展开更多
关键词 Probability theory Mathematical statistics Ideological and political education in courses Fostering virtue through education Construction path
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Visualising data distributions with kernel density estimation and reduced chi-squared statistic 被引量:8
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作者 C.J.Spencer C.Yakymchuk M.Ghaznavi 《Geoscience Frontiers》 SCIE CAS CSCD 2017年第6期1247-1252,共6页
The application of frequency distribution statistics to data provides objective means to assess the nature of the data distribution and viability of numerical models that are used to visualize and interpret data.Two c... The application of frequency distribution statistics to data provides objective means to assess the nature of the data distribution and viability of numerical models that are used to visualize and interpret data.Two commonly used tools are the kernel density estimation and reduced chi-squared statistic used in combination with a weighted mean.Due to the wide applicability of these tools,we present a Java-based computer application called KDX to facilitate the visualization of data and the utilization of these numerical tools. 展开更多
关键词 Data visualisation KERNEL DENSITY estimation REDUCED chi-squared statistic Mean SQUARE WEIGHTED deviation GEOstatistics
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Efficient ECG classification based on Chi-square distance for arrhythmia detection 被引量:1
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作者 Dhiah Al-Shammary Mustafa Noaman Kadhim +2 位作者 Ahmed M.Mahdi Ayman Ibaida Khandakar Ahmedb 《Journal of Electronic Science and Technology》 EI CAS CSCD 2024年第2期1-15,共15页
This study introduces a new classifier tailored to address the limitations inherent in conventional classifiers such as K-nearest neighbor(KNN),random forest(RF),decision tree(DT),and support vector machine(SVM)for ar... This study introduces a new classifier tailored to address the limitations inherent in conventional classifiers such as K-nearest neighbor(KNN),random forest(RF),decision tree(DT),and support vector machine(SVM)for arrhythmia detection.The proposed classifier leverages the Chi-square distance as a primary metric,providing a specialized and original approach for precise arrhythmia detection.To optimize feature selection and refine the classifier’s performance,particle swarm optimization(PSO)is integrated with the Chi-square distance as a fitness function.This synergistic integration enhances the classifier’s capabilities,resulting in a substantial improvement in accuracy for arrhythmia detection.Experimental results demonstrate the efficacy of the proposed method,achieving a noteworthy accuracy rate of 98% with PSO,higher than 89% achieved without any previous optimization.The classifier outperforms machine learning(ML)and deep learning(DL)techniques,underscoring its reliability and superiority in the realm of arrhythmia classification.The promising results render it an effective method to support both academic and medical communities,offering an advanced and precise solution for arrhythmia detection in electrocardiogram(ECG)data. 展开更多
关键词 Arrhythmia classification chi-square distance Electrocardiogram(ECG)signal Particle swarm optimization(PSO)
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Effect Evaluation of CBL Combined with Rain Classroom Teaching Method in Medical Statistics 被引量:3
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作者 Man Luo Xiaofang Zhang Wei Liu 《Open Journal of Applied Sciences》 2024年第5期1204-1213,共10页
Objective: To explore the application effect of CBL combined with rain classroom teaching method in medical statistics courses. Methods: The undergraduate students of medical imaging technology in 2019 and 2020 in a u... Objective: To explore the application effect of CBL combined with rain classroom teaching method in medical statistics courses. Methods: The undergraduate students of medical imaging technology in 2019 and 2020 in a university were selected as the research objects. A cluster sampling method was used to select 79 undergraduate students from 2019 in the control group and 75 undergraduate students from 2020 in the experimental group. Traditional teaching method and CBL combined with rain classroom teaching method was used in the control group and experimental group respectively. The final examination scores of the two groups were compared. In experimental group, the correlation between the average score in the rain classroom and the final examination score was tested, and the teaching effect was evaluated. Results: The average score of final examination in experimental group and control group was 79.13 ± 10.32 points and 71.54 ± 14.752 points, respectively, which had a statistically significant difference (Z = 2.586, P = 0.012);the final examination scores of the students in the experimental group were positively correlated with the average scores of the rain classroom (r = 0.372, P = 0.001), and the proportion of satisfaction in the experimental group was 94.7%. Conclusion: The CBL combined with rain classroom teaching method can improve the teaching effectiveness of medical statistics courses. 展开更多
关键词 Rain Classroom CBL Medical statistics
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Lottery Numbers and Ordered Statistics
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作者 Kung-Kuen Tse 《Applied Mathematics》 2024年第4期287-291,共5页
The lottery has long captivated the imagination of players worldwide, offering the tantalizing possibility of life-changing wins. While winning the lottery is largely a matter of chance, as lottery drawings are typica... The lottery has long captivated the imagination of players worldwide, offering the tantalizing possibility of life-changing wins. While winning the lottery is largely a matter of chance, as lottery drawings are typically random and unpredictable. Some people use the lottery terminal randomly generates numbers for them, some players choose numbers that hold personal significance to them, such as birthdays, anniversaries, or other important dates, some enthusiasts have turned to statistical analysis as a means to analyze past winning numbers identify patterns or frequencies. In this paper, we use order statistics to estimate the probability of specific order of numbers or number combinations being drawn in future drawings. 展开更多
关键词 LOTTERY Order statistics Hypergeometric Distribution EXPECTATION UNIFORM
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Load Statistics Priority Random Access Technology Based on Air-Space-Ground Integrated Network
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作者 Enze Li Hao Huan +1 位作者 Jingyu Wang Kunshan Yang 《Journal of Beijing Institute of Technology》 EI CAS 2024年第6期493-506,共14页
In today's world where everything is interconnected, air-space-ground integrated networks have become a current research hotspot due to their characteristics of high, long and wide area coverage. Given the constan... In today's world where everything is interconnected, air-space-ground integrated networks have become a current research hotspot due to their characteristics of high, long and wide area coverage. Given the constantly changing and dynamic characteristics of air and space networks, along with the sheer number and complexity of access nodes involved, the process of rapid networking presents substantial challenges. In order to achieve rapid and dynamic networking of air-space-ground integrated networks, this paper focuses on the study of methods for large-scale nodes to randomly access satellites. This paper utilizes a cross-layer design methodology to enhance the access success probability by jointly optimizing the physical layer and medium access control(MAC) layer aspects. Load statistics priority random access(LSPRA) technology is proposed.Experiments show that when the number of nodes is greater than 1 000, this method can also ensure stable access performance, providing ideas for the design of air-space-ground integrated network access systems. 展开更多
关键词 air-space-ground integrated network random access satellite-to-ground statistics priority access success probability
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Innovations and Challenges in Economic Census Methodology:A Study by the Bureau of Statistics
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作者 Suqing Li 《Proceedings of Business and Economic Studies》 2024年第5期145-150,共6页
The Bureau of Statistics has demonstrated a forward-looking strategic approach in its economic census.By leveraging dual innovations in technology and management,and incorporating modern technologies such as big data,... The Bureau of Statistics has demonstrated a forward-looking strategic approach in its economic census.By leveraging dual innovations in technology and management,and incorporating modern technologies such as big data,cloud computing,and the Internet of Things,it has deepened the reform of the census methodology.Additionally,the Bureau has built a multi-dimensional collaborative network that enhances international cooperation,departmental coordination,and public participation.This approach not only addresses the limitations of traditional statistical methods in a complex economic environment but also improves data quality and census efficiency,providing an accurate and reliable foundation for national economic decision-making. 展开更多
关键词 Economic census METHODOLOGY Bureau of statistics
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Research on the Application of PBL+SPOC Blended Teaching Model in Probability and Statistics Course
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作者 Hairong Li 《Journal of Contemporary Educational Research》 2024年第9期63-68,共6页
To cultivate talents with an exploratory spirit and practical skills in the era of information technology,it is imperative to reform teaching methods and approaches.In the teaching process of the Probability and Stati... To cultivate talents with an exploratory spirit and practical skills in the era of information technology,it is imperative to reform teaching methods and approaches.In the teaching process of the Probability and Statistics course,an application-oriented blended teaching model combining problem-based learning and small private online course was explored.By organizing and implementing online and offline teaching activities based on problem-based learning,a multidimensional process-oriented learning assessment system was established.Practice has shown that this model can effectively enhance classroom teaching effectiveness,benefiting the improvement of students’overall skills and mathematical literacy. 展开更多
关键词 Problem-based learning teaching method Blended learning Probability and statistics
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Integration of Ideological and Political Education into the Probability Theory and Mathematical Statistics Course:A Teaching Design Based on Estimation and Hypothesis Testing
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作者 Guangyu Li 《Journal of Contemporary Educational Research》 2024年第9期248-254,共7页
With the rapid development of higher education in China,colleges and universities are facing new challenges and impacts in talent training.Probability Theory and Mathematical Statistics is one of the important courses... With the rapid development of higher education in China,colleges and universities are facing new challenges and impacts in talent training.Probability Theory and Mathematical Statistics is one of the important courses in higher education for science and engineering majors and economics and management majors.Its critical role in cultivating students’thinking skills and improving their problem-solving skills is self-evident.Course ideological and political education construction is an important link in college talent training work.Combining ideological and political education with course teaching can help students establish correct value concepts and play a certain role in improving their comprehensive ability and quality.At present,the construction of ideological and political education in the Probability Theory and Mathematical Statistics course still faces some problems,mainly manifested in the lack of attention paid by teachers to course ideological and political education,insufficient exploitation of ideological and political elements,and the simplification of ideological and political education implementation methods.In order to comprehensively deepen the construction of course ideological and political education in line with the actual needs of Probability Theory and Mathematical Statistics course teaching,we should strengthen the construction of teacher teams,improve teachers’ability to carry out course ideological and political education,integrate educational resources,develop educational resources for ideological and political education,and innovate teaching methods to improve the overall effect of ideological and political education integration. 展开更多
关键词 Probability Theory and Mathematical statistics Course education Teaching strategy
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Generalized Kumaraswamy Generalized Power Gompertz Distribution: Statistical Properties, Application, and Validation Using a Modified Chi-Squared Goodness of Fit Test
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作者 Obubu Maxwell Ibeakuzie Precious Onyedikachi +2 位作者 Khaoula Aidi Chijioke Igwe Akpa Nacira Seddik-Ameur 《Applied Mathematics》 2022年第3期243-262,共20页
A new six-parameter continuous distribution called the Generalized Kumaraswamy Generalized Power Gompertz (GKGPG) distribution is proposed in this study, a graphical illustration of the probability density function an... A new six-parameter continuous distribution called the Generalized Kumaraswamy Generalized Power Gompertz (GKGPG) distribution is proposed in this study, a graphical illustration of the probability density function and cumulative distribution function is presented. The statistical features of the Generalized Kumaraswamy Generalized Power Gompertz distribution are systematically derived and adequately studied. The estimation of the model parameters in the absence of censoring and under-right censoring is performed using the method of maximum likelihood. The test statistic for right-censored data, criteria test for GKGPG distribution, estimated matrix &#372;, &#264;, and &#284;, criteria test Y<sup>2</sup>n</sub>, alongside the quadratic form of the test statistic is derived. Mean simulated values of maximum likelihood estimates and their corresponding square mean errors are presented and confirmed to agree closely with the true parameter values. Simulated levels of significance for Y<sup>2</sup>n</sub> (γ) test for the GKGPG model against their theoretical values were recorded. We conclude that the null hypothesis for which simulated samples are fitted by GKGPG distribution is widely validated for the different levels of significance considered. From the summary of the results of the strength of a specific type of braided cord dataset on the GKGPG model, it is observed that the proposed GKGPG model fits the data set for a significance level ε = 0.05. 展开更多
关键词 Power Gompertz Generalized Kumaraswamy-G Modified chi-squared the Goodness of Fit CENSORING
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A Simple Chi-Square Statistic for Testing Homogeneity of Zero-Inflated Distributions
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作者 William D. Johnson Jeffrey H. Burton +1 位作者 Robbie A. Beyl Jacob E. Romer 《Open Journal of Statistics》 2015年第6期483-493,共11页
Zero-inflated distributions are common in statistical problems where there is interest in testing homogeneity of two or more independent groups. Often, the underlying distribution that has an inflated number of zero-v... Zero-inflated distributions are common in statistical problems where there is interest in testing homogeneity of two or more independent groups. Often, the underlying distribution that has an inflated number of zero-valued observations is asymmetric, and its functional form may not be known or easily characterized. In this case, comparisons of the groups in terms of their respective percentiles may be appropriate as these estimates are nonparametric and more robust to outliers and other irregularities. The median test is often used to compare distributions with similar but asymmetric shapes but may be uninformative when there are excess zeros or dissimilar shapes. For zero-inflated distributions, it is useful to compare the distributions with respect to their proportion of zeros, coupled with the comparison of percentile profiles for the observed non-zero values. A simple chi-square test for simultaneous testing of these two components is proposed, applicable to both continuous and discrete data. Results of simulation studies are reported to summarize empirical power under several scenarios. We give recommendations for the minimum sample size which is necessary to achieve suitable test performance in specific examples. 展开更多
关键词 Asymptotic chi-square TEST EQUALITY of QUANTILES Large Sample TEST Nonparametric TEST Percentile Profiles ZERO-INFLATED DISTRIBUTIONS
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Research on the Development of International Trade in Services Statistical System
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作者 NI Kun 《International Relations and Diplomacy》 2025年第5期270-274,共5页
This article focuses on the development of the international service trade statistics system.The 1994 General Agreement on Trade in Services(GATS)provided a institutional basis for service trade statistics.The 2002“I... This article focuses on the development of the international service trade statistics system.The 1994 General Agreement on Trade in Services(GATS)provided a institutional basis for service trade statistics.The 2002“International Service Trade Statistics Manual”(MSITS 2002)established the international balance of payments statistics paradigm.The revised MSITS 2010 in 2010 introduced the expanded balance of payments service classification(EBOPS 2010),incorporating foreign affiliate service trade statistics(FATS),and constructing a comprehensive statistics system.The update of MSITS 2010 originated from changes in the global economic environment,technological progress leading to diversified forms of service trade,and the demands of international service trade negotiations.This standard has constructed a multi-level classification system.Since the release of MSITS 2010,many countries have implemented the new statistical framework,but some developing countries face challenges.International organizations and developed countries have provided corresponding support for service trade statistics standards. 展开更多
关键词 international service trade statistical system MSITS 2010
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Transforming Medical Education:Cultivating Statistical Thinking in the AI Era
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作者 Songhua Hu Yingshui Yao +1 位作者 Jiao Tan Yan Chen 《Journal of Contemporary Educational Research》 2025年第10期238-252,共15页
Artificial intelligence(AI)is rapidly transforming healthcare and medical education.Strong statistical thinking skills are vital for evaluating and applying AI tools.However,traditional medical statistics education ha... Artificial intelligence(AI)is rapidly transforming healthcare and medical education.Strong statistical thinking skills are vital for evaluating and applying AI tools.However,traditional medical statistics education has not adapted to this demand.This paper first analyzes the connotation and importance of statistical thinking,points out the significant challenges currently faced by medical statistics education,and then proposes strategies such as innovative teaching methods combined with evidence-based medicine,utilizing AI platforms for supplemental teaching,multidisciplinary integration,and strengthening the understanding of the statistical foundations of AI to enhance the statistical thinking abilities of medical professionals.This study emphasizes the importance of cultivating medical statistical thinking in the era of AI to improve the quality of medical education and ensure the safety and effectiveness of future medical services. 展开更多
关键词 Artificial intelligence Medical education statistical thinking Cultivation strategies
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A statistical survey of polar cap cold and hot patches in the Southern Hemisphere using a DMSP Satellite
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作者 Duan Zhang QingHe Zhang +11 位作者 Kjellmar Oksavik ZanYang Xing LRLyons HuiGen Yang Tong Xu Marc Hairston XiangYu Wang YuZhang Ma GuoJun Li Yong Wang Sheng Lu Jin Wang 《Earth and Planetary Physics》 2025年第4期955-965,共11页
This paper is a statistical survey of Southern Hemisphere cold and hot polar cap patches,in relation to the interplanetary magnetic field(IMF)and ionospheric convection geometry.A total of 11,946 patch events were ide... This paper is a statistical survey of Southern Hemisphere cold and hot polar cap patches,in relation to the interplanetary magnetic field(IMF)and ionospheric convection geometry.A total of 11,946 patch events were identified by Defense Meteorological Satellite Program(DMSP)F16 during the years 2011 to 2022.A temperature ratio of ion/electron temperature(T_(i)/T_(e))<0.68 is recommended to define a hot patch in the Southern Hemisphere,otherwise it is defined as a cold patch.The cold and hot patches have different dependencies on IMF clock angle,while their dependencies on IMF cone angle are similar.Both cold and hot patches appear most often on the duskside,and the distribution of cold patches gradually decreases from the dayside to the nightside,while hot patches have a higher occurrence rate near 14 and 21 magnetic local time(MLT).Moreover,we compared the key plasma characteristics of polar cap cold and hot patches in the Southern and Northern Hemispheres.The intensity of the duskside upward field-aligned current of patches in the Southern Hemisphere(SH)is stronger than that in the Northern Hemisphere(SH),which may be due to the discrepancy in conductivities between the two hemispheres,caused by the tilted dipole.In both hemispheres,the downward soft-electron energy flux of the dawnside patches is significantly greater than that of the duskside patches. 展开更多
关键词 polar ionosphere polar cap patch IRREGULARITIES statistical survey southern hemisphere.
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USDE:An Unsupervised Web Data Extraction Method Based on Statistical Characteristics
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作者 Sun Long 《China Communications》 2025年第9期307-319,共13页
Web data extraction has become a key technology for extracting valuable data from websites.At present,most extraction methods based on rule learning,visual pattern or tree matching have limited performance on complex ... Web data extraction has become a key technology for extracting valuable data from websites.At present,most extraction methods based on rule learning,visual pattern or tree matching have limited performance on complex web pages.Through ana-lyzing various statistical characteristics of HTML el-ements in web documents,this paper proposes,based on statistical features,an unsupervised web data ex-traction method—traversing the HTML DOM parse tree at first,calculating and generating the statistical matrix of the elements,and then locating data records by clustering method and heuristic rules that reveal in-herent links between the visual characteristics of the data recording areas and the statistical characteristics of the HTML nodes—which is both suitable for data records extraction of single-page and multi-pages,and it has strong generality and needs no training.The ex-periments show that the accuracy and efficiency of this method are equally better than the current data extrac-tion method. 展开更多
关键词 cluster method statistical feature unsupervised technique web information extraction
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Statistical Study on the Thermodynamic Effect of Distant Disturbances Caused by Tropical Cyclones
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作者 Qinshuang SUN Ju WANG +4 位作者 Tianju WANG Yiyang PAN Chenhan LIU Zixuan WANG Yicheng ZHOU 《Meteorological and Environmental Research》 2025年第3期16-21,共6页
Multi-angle statistical analysis of tropical cyclones(TCs)and their distant thermodynamic disturbances over Northwest Pacific from July to September during 2001-2020 was conducted.The results show that TCs could trigg... Multi-angle statistical analysis of tropical cyclones(TCs)and their distant thermodynamic disturbances over Northwest Pacific from July to September during 2001-2020 was conducted.The results show that TCs could trigger distant thermodynamic disturbances,which mainly caused an increase in air pressure and a rise in temperature in northern China.The distant thermodynamic disturbances triggered by TCs differed in spatial distribution and intensity in different months.In the same month,the spatial distribution of such disturbances triggered by high-intensity TCs was consistent with the overall pattern,and there was a significant increase in intensity and area.From the probability of TC activities and the significance test of variance of analysis under different levels of P-J index,it is found that TC activities could stimulate the increase of P-J teleconnection index.There was a significant positive correlation between them,which was accompanied by a step effect. 展开更多
关键词 Teleconnection quantity statistical analysis Significance test Distant disturbance Thermodynamic effect
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Statistical analysis of regional STEC gradient trends for midlatitude ionosphere
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作者 Meltem Koroglu Feza Arikan 《Geodesy and Geodynamics》 2025年第1期7-28,共22页
In this study,the gradients of Total Electron Content(TEC)for a midlatitude region are estimated and grouped with respect to the distance between neighboring stations,time periods within a day,and satellite directions... In this study,the gradients of Total Electron Content(TEC)for a midlatitude region are estimated and grouped with respect to the distance between neighboring stations,time periods within a day,and satellite directions.Annual medians of these gradients for quiet days are computed as templates.The metric distances(L2N)and Symmetric Kullback-Leibler Distances(SKLD)are obtained between the templates and the daily gradient series.The grouped histograms are fitted to the prospective Probability Density Functions(PDF).The method is applied to the Slant Total Electron Content(STEC)estimates from the Turkish National Permanent GPS Network(TNPGN-Active)for 2015.The highest gradients are observed in the east-west axis with a maximum of 25 mm/km during a geomagnetic storm.The maximum differences from the gradient templates occur for neighboring stations within100-130 km distance away from each other,during night hours,and for regions bordering the Black Sea and the Mediterranean in the northeast and southeast of Turkey.The empirical PDFs of the stationpair gradients are predominantly Weibull-distributed.The mean values of Weibull PDFs in all station groups are between 1.2 and 1.8 mm/km,with an increase during noon and afternoon hours.The standard deviations of the gradient PDFs generally increase during night hours.The algorithm will form a basis for quantifying the stochastic variations of the spatial rate of change of TEC trends in midlatitude regions,thus supplementing reliable and accurate regional monitoring of ionospheric variability. 展开更多
关键词 onospheric disturbances lonospheric gradient statistical modeling Ground based augmentation system
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Extratropical Transition of Tropical Cyclones in the Western North Pacific:PartⅠ.Statistical Characteristics
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作者 CHEN Ming-hua ZHAN Rui-fen +1 位作者 WANG Yu-qing LU Xiao-qin 《Journal of Tropical Meteorology》 2025年第5期453-466,共14页
Extratropical transition(ET)is one of the last phases of tropical cyclones(TCs)and corresponds to the structural change from a tropical system to an extratropical system characterized by pronounced asymmetric distribu... Extratropical transition(ET)is one of the last phases of tropical cyclones(TCs)and corresponds to the structural change from a tropical system to an extratropical system characterized by pronounced asymmetric distributions of heavy rainfall and strong wind.This study analyzes the statistical characteristics of ET events involving TCs over the western North Pacific(WNP)during 1981–2022.The analysis employs the Cyclone Phase Space(CPS)method to evaluate the accuracy of the fifth-generation reanalysis from the European Centre for Medium-Range Weather Forecasts(ERA5)in identifying ET based on different TC center definitions.Results show that defining the TC center by the minimum sea level pressure yields the most accurate ET identification.Subsequently,the study investigates several characteristics of ET events in the WNP.It is found that TCs undergoing ET(ETTCs)primarily form in the region of 125°–155°E,10°–25°N,with ET typically initiating between 30°–40°N and completing between 35°–50°N.These ETTCs predominantly occur from April to December,with peak activity observed from August to October.Additionally,the average duration of the ET process is 18.5 h,with longer durations observed from August to October,displaying a roughly 6-year cycle.Spatially,ET events with longer durations tend to occur at lower latitudes.Correspondingly,TCs initiating their ET phase at lower latitudes are typically stronger and larger,and they also experience longer ET durations. 展开更多
关键词 extratropical transition western North Pacific cyclone phase space statistical characteristics
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Comparison of the Statistical Power of Siegel-Tukey and Savage Tests: A Study with Monte Carlo Simulation
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作者 Elnur Hasan Mikail HakanÇora Sahib Ramazanov 《Economics World》 2025年第2期95-105,共11页
This study presents the results of a Monte Carlo simulation to compare the statistical power of Siegel-Tukey and Savage tests.The main purpose of the study is to evaluate the statistical power of both tests in scenari... This study presents the results of a Monte Carlo simulation to compare the statistical power of Siegel-Tukey and Savage tests.The main purpose of the study is to evaluate the statistical power of both tests in scenarios involving Normal,Platykurtic and Skewed distributions over different sample sizes and standard deviation values.In the study,standard deviation ratios were set as 2,3,4,1/2,1/3 and 1/4 and power comparisons were made between small and large sample sizes.For equal sample sizes,small sample sizes of 5,8,10,12,16 and 20 and large sample sizes of 25,50,75 and 100 were used.For different sample sizes,the combinations of(4,16),(8,16),(10,20),(16,4),(16,8)and(20,10)small sample sizes and(10,30),(30,10),(50,75),(50,100),(75,50),(75,100),(100,50)and(100,75)large sample sizes were examined in detail.According to the findings,the power analysis under variance heterogeneity conditions shows that the Siegel-Tukey test has a higher statistical power than the other nonparametric Savage test at small and large sample sizes.In particular,the Siegel-Tukey test was reported to offer higher precision and power under variance heterogeneity,regardless of having equal or different sample sizes. 展开更多
关键词 nonparametric test statistical power Siegel-Tukey test Savage test Monte Carlo simulation
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