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
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
This paper surveys the current state of teaching spatial statistics in the United States(US),with commentary about the future teaching of such a course.It begins with a historical overview,and proposes what constitute...This paper surveys the current state of teaching spatial statistics in the United States(US),with commentary about the future teaching of such a course.It begins with a historical overview,and proposes what constitutes suitable content for a contemporary spatial statistics course.It notes that contemporary university-level spatial statistics courses are mostly taught across myriad units,including biology/ecology,climatology,economics(as spatial econometrics),environmental studies,epidemiology/public health,forestry,geography,geosciences/earth sciences,geospatial information sciences,mathematics,quantitative social science,soil science,and statistics.It discusses the diffusion of this course across the US,which began in the mid-1980s.One result it reports is a model spatial statistics course offering.展开更多
Variation of reservoir physical properties can cause changes in its elastic parameters. However, this is not a simple linear relation. Furthermore, the lack of observations, data overlap, noise interference, and ideal...Variation of reservoir physical properties can cause changes in its elastic parameters. However, this is not a simple linear relation. Furthermore, the lack of observations, data overlap, noise interference, and idealized models increases the uncertainties of the inversion result. Thus, we propose an inversion method that is different from traditional statistical rock physics modeling. First, we use deterministic and stochastic rock physics models considering the uncertainties of elastic parameters obtained by prestack seismic inversion and introduce weighting coefficients to establish a weighted statistical relation between reservoir and elastic parameters. Second, based on the weighted statistical relation, we use Markov chain Monte Carlo simulations to generate the random joint distribution space of reservoir and elastic parameters that serves as a sample solution space of an objective function. Finally, we propose a fast solution criterion to maximize the posterior probability density and obtain reservoir parameters. The method has high efficiency and application potential.展开更多
In order to reduce the enormous pressure to environmental monitoring work brought by the false sewage monitoring data, Grubbs method, box plot, t test and other methods are used to make depth analysis to the data, pro...In order to reduce the enormous pressure to environmental monitoring work brought by the false sewage monitoring data, Grubbs method, box plot, t test and other methods are used to make depth analysis to the data, providing a set of technological process to identify the sewage monitoring data, which is convenient and simple.展开更多
Gentile statistics describes fractional statistical systems in the occupation number representation.Anyon statistics researches those systems in the winding number representation.Both of them are intermediate statisti...Gentile statistics describes fractional statistical systems in the occupation number representation.Anyon statistics researches those systems in the winding number representation.Both of them are intermediate statistics between Bose–Einstein and Fermi–Dirac statistics.The second quantization of Gentile statistics shows a lot of advantages.According to the symmetry requirement of the wave function and the property of braiding,we give the general construction of transformation between anyon and Gentile statistics.In other words,we introduce the second quantization form of anyons in an easier way.This construction is a correspondence between two fractional statistics and gives a new description of anyon.Basic relations of second quantization operators,the coherent state and Berry phase are also discussed.展开更多
Clusters traverse a gas and collide with gas particles. The gas particles are absorbed, and the clusters become hosts. If the clusters are size-selected, the number of vips will be Poisson distributed. We review thi...Clusters traverse a gas and collide with gas particles. The gas particles are absorbed, and the clusters become hosts. If the clusters are size-selected, the number of vips will be Poisson distributed. We review this by showcasing four laboratory procedures that all rely on the validity of the Poisson model. The effects of a statistical distribution of the clusters＇ sizes in a beam of clusters are discussed. We derive the average collision rates. Additionally, we present Poisson mixture models that also involve standard deviations. We derive the collision statistics for common size distributions of hosts and also for some generalizations thereof. The models can be applied to large noble gas clusters traversing doping gas. While outlining how to fit a generalized Poisson to the statistics, we still find even these Poisson models to be often insufficient.展开更多
With the illustration of a specific problem, this paper demonstrates that using Monte Carlo Simulation technology will improve intuitive effect of teaching Probability and Mathematical Statistics course, and save inst...With the illustration of a specific problem, this paper demonstrates that using Monte Carlo Simulation technology will improve intuitive effect of teaching Probability and Mathematical Statistics course, and save instructors' effort as well.And it is estimated that Monte Carlo Simulation technology will be one of the major teaching methods for Probability and Mathematical Statistics course in the future.展开更多
In both academic research and policymaking,public sector debt and debt-to-GDP ratios are relied on for a multitude of important economic,political and socioeconomic decisions,especially as public sector balance sheets...In both academic research and policymaking,public sector debt and debt-to-GDP ratios are relied on for a multitude of important economic,political and socioeconomic decisions,especially as public sector balance sheets expand to an unprecedented size in the midst of the 2019–2020 COVID pandemic.The reliance on available data from reputable sources often overlooks the question of whether the denominator in this ratio is accurately measured or how well the denominator is understood by the audience interpreting it.Building on past work in international financial statistics,and making use of a unique and newly created dataset on media reporting of public sector debt,the purpose of this article is to examine the quality,accuracy,interpretation and overall meaningfulness of public sector financial statistics.The main findings suggest that i)most of the world’s governments still do not seem to feel sufficient pressure to voluntarily provide comprehensive financial statistics based on well-defined modern methodological frameworks and ii)high profile financial statistics,which are reported,have become increasingly numerous and complicated,making it difficult for non-experts to know which is most appropriate in the context of their analysis.展开更多
Let - be i.i.d. random variables taking values in a measurable space ( Χ, B ). Let φ1: Χ →□ and φ: Χ2→□ be measurable functions. Assume that φ is symmetric, i.e. φ(x,y)=φ(y.x), for any x,y∈Χ . Consider U...Let - be i.i.d. random variables taking values in a measurable space ( Χ, B ). Let φ1: Χ →□ and φ: Χ2→□ be measurable functions. Assume that φ is symmetric, i.e. φ(x,y)=φ(y.x), for any x,y∈Χ . Consider U-statistic, assuming that Eφ1(Χ)=0, Eφ(x, X)=0 for all x∈X, Eφ2(x,X)<∞, Eφ21(X)<∞. We will provide bounds for ΔN=supx|F(x)-F0(x)-F1(x)|, where F is a distribution function of T and F0 , F1 are its limiting distribution function and Edgeworth correction respectively. Applications of these results are also provided for von Mises statistics case.展开更多
After the proposal of a possible insertion of tourism statistics （supply side） （TS） into Framework Regulation Integrating Business Statistics （FR1BS） on which an interesting debate is in progress between Eurosta...After the proposal of a possible insertion of tourism statistics （supply side） （TS） into Framework Regulation Integrating Business Statistics （FR1BS） on which an interesting debate is in progress between Eurostat and NSls, Istat （Italian Institute of Statistics） has started a costs/benefits analysis of this integration. ASIA （Statistical Register of Active Enterprises）, built up by Istat, represents in Italy the official source about the structure and the economic performance of the enterprises. ASIA, whose statistical units are enterprises of industry and services, has been developed through the statistical integration of different administrative sources, other minor archives available （covering particular sectors） and structural business statistics currently produced by Istat. The supply side TS are produced by lstat through surveys via Intermediate Bodies （Local Authorities）： each Intermediate Body has its own local register of accommodation establishments based on Local Kind-of-activity unit （LKAU）. In this paper, the results of a comparative analysis between the statistical units as recorded in ASIA and as surveyed by TS are presented; from first outcomes, considerable issues about data quality appear both at level of coverage for the three Nace groups of the TS （also underlined in the Methodological Manual on Tourism Statistics where for Italy a difference of 70% is reported） and for loss information relating to the location of the activities （switching from LKAU to Enterprises） as well as for timeliness （ASIA has two years of delay）. Then, the administrative local tourism registers （LTR） are analysed to understand： how many they are, their dissemination in the Italian territories, their primary purpose and source, the variables contained, the frequency of updates. This preliminary analysis is needed to identify the operative activities that Istat, together with the Intermediate Bodies, should start to use administrative archives for statistical purposes and to develop a unique tourism satellite archive （TSA）, facing many difficulties related to the reception of several LTR as well as methodological issues for record linkage. On the other hand, a TSA would lead numerous advantages： a unique and official list of internal accommodation establishments; a step towards integration of TS into FRIBS; a starting point to begin to use also administrative data produced by the Italian Police （mandatory communications on vips in the interests of public safety）, having a comparison term to assess their coverage.展开更多
“Four classes of enterprises above designated size”(hereinafter called four-classes enterprises)refer to objects of statistical survey that have reached a certain scale in China’s current statistical method system,...“Four classes of enterprises above designated size”(hereinafter called four-classes enterprises)refer to objects of statistical survey that have reached a certain scale in China’s current statistical method system,including four classes in national economy,namely,industrial enterprises above designated size,construction and real estate development and management enterprises above qualifications,wholesale and retail,catering and accommodation enterprises,and service enterprises above designated size,which are the primary part of national economic and social development activities.This paper is focused on analyzing the practice and difficulties in the current statistics work of four-classes enterprises,and then this paper proposes some recommendations.展开更多
Cancer is a major public health issue in most of countries, including China. Accurate and valid information on cancer incidence, mortality, survival and relevant factors is irreplaceable for cancer prevention and cont...Cancer is a major public health issue in most of countries, including China. Accurate and valid information on cancer incidence, mortality, survival and relevant factors is irreplaceable for cancer prevention and control. Since the national program of cancer registry was launched by the Ministry of Health of China in 2008, the National Central Cancer Registry （NCCR） has been releasing the cancer incidence and mortality based on the data collected from cancer registries supported by the program. The cancer statistics provide current data from registered areas and aims to accurately reflect the cancer burden and epidemic in China. In 2014, the NCCR collected data for calendar year 2011 from 234 registries. After comprehensive quality＇ evaluation, data from 177 registries have been selected as sources of the reports reflecting cancer incidence and mortaliD, in the registration areas in 2011. These reports are the updated cancer statistics so far, covering much more registries and a hig population.展开更多
This paper is mainly to deal with the problem of direction of arrival(DOA) estimations of multiple narrow-band sources impinging on a uniform linear array under impulsive noise environments. By modeling the impulsive ...This paper is mainly to deal with the problem of direction of arrival(DOA) estimations of multiple narrow-band sources impinging on a uniform linear array under impulsive noise environments. By modeling the impulsive noise as α-stable distribution, new methods which combine the sparse signal representation technique and fractional lower order statistics theory are proposed. In the new algorithms, the fractional lower order statistics vectors of the array output signal are sparsely represented on an overcomplete basis and the DOAs can be effectively estimated by searching the sparsest coefficients. To enhance the robustness performance of the proposed algorithms,the improved algorithms are advanced by eliminating the fractional lower order statistics of the noise from the fractional lower order statistics vector of the array output through a linear transformation. Simulation results have shown the effectiveness of the proposed methods for a wide range of highly impulsive environments.展开更多
Ocean waves are the core environmental elements affecting the movements and structure design of ships. Statistical analysis of wave parameters is the basis for the establishment of long-term ship environmental adaptab...Ocean waves are the core environmental elements affecting the movements and structure design of ships. Statistical analysis of wave parameters is the basis for the establishment of long-term ship environmental adaptability prediction model. The observations from coastal stations, buoys, altimeters and volunteer ships that cover from 1993 to 2011 were interpolated into miller Ion-lat grids by using bilinear method and the analytical fields of ocean waves were given. By using optimal interpolation, the analysis wave fields were assimilated into the WAVEWATCH III （WW3） simulation results. From the assimilated results, the wave rose statistics, the wave height of muitiyear return period and the extreme 2-D wave spectrum are related to the ship seakeeping were calculated. Finally, the wave statistics in China offshore were analyzed in detail.展开更多
This paper focuses on a method to solve structural optimization problems using particle swarm optimization （PSO）, surrogate models and Bayesian statistics. PSO is a random/stochastic search algorithm designed to fin...This paper focuses on a method to solve structural optimization problems using particle swarm optimization （PSO）, surrogate models and Bayesian statistics. PSO is a random/stochastic search algorithm designed to find the global optimum. However, PSO needs many evaluations compared to gradient-based optimization. This means PSO increases the analysis costs of structural optimization. One of the methods to reduce computing costs in stochastic optimization is to use approximation techniques. In this work, surrogate models are used, including the response surface method （RSM） and Kriging. When surrogate models are used, there are some errors between exact values and approximated values. These errors decrease the reliability of the optimum values and discard the realistic approximation of using surrogate models. In this paper, Bayesian statistics is used to obtain more reliable results. To verify and confirm the efficiency of the proposed method using surrogate models and Bayesian statistics for stochastic structural optimization, two numerical examples are optimized, and the optimization of a hub sleeve is demonstrated as a practical problem.展开更多
The relationship between fractal point pattern modeling and statistical methods of pa- rameter estimation in point-process modeling is reviewed. Statistical estimation of the cluster fractal dimension by using Ripley...The relationship between fractal point pattern modeling and statistical methods of pa- rameter estimation in point-process modeling is reviewed. Statistical estimation of the cluster fractal dimension by using Ripley＇s K-function has advantages in comparison with the more commonly used methods of box-counting and cluster fractal dimension estimation because it corrects for edge effects, not only for rectangular study areas but also for study areas with curved boundaries determined by re- gional geology. Application of box-counting to estimate the fractal dimension of point patterns has the disadvantage that, in general, it is subject to relatively strong ＂roll-off＂ effects for smaller boxes. Point patterns used for example in this paper are mainly for gold deposits in the Abitibi volcanic belt on the Canadian Shield. Additionally, it is proposed that, worldwide, the local point patterns of podiform Cr, volcanogenic massive sulphide and porphyry copper deposits, which are spatially distributed within irregularly shaped favorable tracts, satisfy the fractal clustering model with similar fractal dimensions. The problem of deposit size （metal tonnage） is also considered. Several examples are provided of cases in which the Pareto distribution provides good results for the largest deposits in metal size-frequency distribution modeling.展开更多
The problem of two order statistics detection schemes for the detection of a spatially distributed target in white Gaussian noise are studied.When the number of strong scattering cells is known,we first show an optima...The problem of two order statistics detection schemes for the detection of a spatially distributed target in white Gaussian noise are studied.When the number of strong scattering cells is known,we first show an optimal detector,which requires many processing channels.The structure of such optimal detector is complex.Therefore,a simpler quasi-optimal detector is then introduced.The quasi-optimal detector,called the strong scattering cells’ number dependent order statistics（SND-OS） detector,takes the form of an average of maximum strong scattering cells with a known number.If the number of strong scattering cells is unknown in real situation,the multi-channel order statistics（MC-OS） detector is used.In each channel,a various number of maximums scattered from target are averaged.Then,the false alarm probability analysis and thresholds sets for each channel are given,following the detection results presented by means of Monte Carlo simulation strategy based on simulated target model and three measured targets.In particular,the theoretical analysis and simulation results highlight that the MC-OS detector can efficiently detect range-spread targets in white Gaussian noise.展开更多
文摘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.
基金Shaanxi Provincial 14th Five-Year Plan for Educational Science Research(SGH24Q481)。
文摘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.
文摘This paper surveys the current state of teaching spatial statistics in the United States(US),with commentary about the future teaching of such a course.It begins with a historical overview,and proposes what constitutes suitable content for a contemporary spatial statistics course.It notes that contemporary university-level spatial statistics courses are mostly taught across myriad units,including biology/ecology,climatology,economics(as spatial econometrics),environmental studies,epidemiology/public health,forestry,geography,geosciences/earth sciences,geospatial information sciences,mathematics,quantitative social science,soil science,and statistics.It discusses the diffusion of this course across the US,which began in the mid-1980s.One result it reports is a model spatial statistics course offering.
基金supported by the National Science and Technology Major Project(No.2011 ZX05007-006)the 973 Program of China(No.2013CB228604)the Major Project of Petrochina(No.2014B-0610)
文摘Variation of reservoir physical properties can cause changes in its elastic parameters. However, this is not a simple linear relation. Furthermore, the lack of observations, data overlap, noise interference, and idealized models increases the uncertainties of the inversion result. Thus, we propose an inversion method that is different from traditional statistical rock physics modeling. First, we use deterministic and stochastic rock physics models considering the uncertainties of elastic parameters obtained by prestack seismic inversion and introduce weighting coefficients to establish a weighted statistical relation between reservoir and elastic parameters. Second, based on the weighted statistical relation, we use Markov chain Monte Carlo simulations to generate the random joint distribution space of reservoir and elastic parameters that serves as a sample solution space of an objective function. Finally, we propose a fast solution criterion to maximize the posterior probability density and obtain reservoir parameters. The method has high efficiency and application potential.
文摘In order to reduce the enormous pressure to environmental monitoring work brought by the false sewage monitoring data, Grubbs method, box plot, t test and other methods are used to make depth analysis to the data, providing a set of technological process to identify the sewage monitoring data, which is convenient and simple.
基金supported by the Fundamental Research Funds for the Central Universities Grant No.2020JKF306 and NSFC Grant No.11675119。
文摘Gentile statistics describes fractional statistical systems in the occupation number representation.Anyon statistics researches those systems in the winding number representation.Both of them are intermediate statistics between Bose–Einstein and Fermi–Dirac statistics.The second quantization of Gentile statistics shows a lot of advantages.According to the symmetry requirement of the wave function and the property of braiding,we give the general construction of transformation between anyon and Gentile statistics.In other words,we introduce the second quantization form of anyons in an easier way.This construction is a correspondence between two fractional statistics and gives a new description of anyon.Basic relations of second quantization operators,the coherent state and Berry phase are also discussed.
文摘Clusters traverse a gas and collide with gas particles. The gas particles are absorbed, and the clusters become hosts. If the clusters are size-selected, the number of vips will be Poisson distributed. We review this by showcasing four laboratory procedures that all rely on the validity of the Poisson model. The effects of a statistical distribution of the clusters＇ sizes in a beam of clusters are discussed. We derive the average collision rates. Additionally, we present Poisson mixture models that also involve standard deviations. We derive the collision statistics for common size distributions of hosts and also for some generalizations thereof. The models can be applied to large noble gas clusters traversing doping gas. While outlining how to fit a generalized Poisson to the statistics, we still find even these Poisson models to be often insufficient.
文摘With the illustration of a specific problem, this paper demonstrates that using Monte Carlo Simulation technology will improve intuitive effect of teaching Probability and Mathematical Statistics course, and save instructors' effort as well.And it is estimated that Monte Carlo Simulation technology will be one of the major teaching methods for Probability and Mathematical Statistics course in the future.
文摘In both academic research and policymaking,public sector debt and debt-to-GDP ratios are relied on for a multitude of important economic,political and socioeconomic decisions,especially as public sector balance sheets expand to an unprecedented size in the midst of the 2019–2020 COVID pandemic.The reliance on available data from reputable sources often overlooks the question of whether the denominator in this ratio is accurately measured or how well the denominator is understood by the audience interpreting it.Building on past work in international financial statistics,and making use of a unique and newly created dataset on media reporting of public sector debt,the purpose of this article is to examine the quality,accuracy,interpretation and overall meaningfulness of public sector financial statistics.The main findings suggest that i)most of the world’s governments still do not seem to feel sufficient pressure to voluntarily provide comprehensive financial statistics based on well-defined modern methodological frameworks and ii)high profile financial statistics,which are reported,have become increasingly numerous and complicated,making it difficult for non-experts to know which is most appropriate in the context of their analysis.
文摘Let - be i.i.d. random variables taking values in a measurable space ( Χ, B ). Let φ1: Χ →□ and φ: Χ2→□ be measurable functions. Assume that φ is symmetric, i.e. φ(x,y)=φ(y.x), for any x,y∈Χ . Consider U-statistic, assuming that Eφ1(Χ)=0, Eφ(x, X)=0 for all x∈X, Eφ2(x,X)<∞, Eφ21(X)<∞. We will provide bounds for ΔN=supx|F(x)-F0(x)-F1(x)|, where F is a distribution function of T and F0 , F1 are its limiting distribution function and Edgeworth correction respectively. Applications of these results are also provided for von Mises statistics case.
文摘After the proposal of a possible insertion of tourism statistics （supply side） （TS） into Framework Regulation Integrating Business Statistics （FR1BS） on which an interesting debate is in progress between Eurostat and NSls, Istat （Italian Institute of Statistics） has started a costs/benefits analysis of this integration. ASIA （Statistical Register of Active Enterprises）, built up by Istat, represents in Italy the official source about the structure and the economic performance of the enterprises. ASIA, whose statistical units are enterprises of industry and services, has been developed through the statistical integration of different administrative sources, other minor archives available （covering particular sectors） and structural business statistics currently produced by Istat. The supply side TS are produced by lstat through surveys via Intermediate Bodies （Local Authorities）： each Intermediate Body has its own local register of accommodation establishments based on Local Kind-of-activity unit （LKAU）. In this paper, the results of a comparative analysis between the statistical units as recorded in ASIA and as surveyed by TS are presented; from first outcomes, considerable issues about data quality appear both at level of coverage for the three Nace groups of the TS （also underlined in the Methodological Manual on Tourism Statistics where for Italy a difference of 70% is reported） and for loss information relating to the location of the activities （switching from LKAU to Enterprises） as well as for timeliness （ASIA has two years of delay）. Then, the administrative local tourism registers （LTR） are analysed to understand： how many they are, their dissemination in the Italian territories, their primary purpose and source, the variables contained, the frequency of updates. This preliminary analysis is needed to identify the operative activities that Istat, together with the Intermediate Bodies, should start to use administrative archives for statistical purposes and to develop a unique tourism satellite archive （TSA）, facing many difficulties related to the reception of several LTR as well as methodological issues for record linkage. On the other hand, a TSA would lead numerous advantages： a unique and official list of internal accommodation establishments; a step towards integration of TS into FRIBS; a starting point to begin to use also administrative data produced by the Italian Police （mandatory communications on vips in the interests of public safety）, having a comparison term to assess their coverage.
文摘“Four classes of enterprises above designated size”(hereinafter called four-classes enterprises)refer to objects of statistical survey that have reached a certain scale in China’s current statistical method system,including four classes in national economy,namely,industrial enterprises above designated size,construction and real estate development and management enterprises above qualifications,wholesale and retail,catering and accommodation enterprises,and service enterprises above designated size,which are the primary part of national economic and social development activities.This paper is focused on analyzing the practice and difficulties in the current statistics work of four-classes enterprises,and then this paper proposes some recommendations.
文摘Cancer is a major public health issue in most of countries, including China. Accurate and valid information on cancer incidence, mortality, survival and relevant factors is irreplaceable for cancer prevention and control. Since the national program of cancer registry was launched by the Ministry of Health of China in 2008, the National Central Cancer Registry （NCCR） has been releasing the cancer incidence and mortality based on the data collected from cancer registries supported by the program. The cancer statistics provide current data from registered areas and aims to accurately reflect the cancer burden and epidemic in China. In 2014, the NCCR collected data for calendar year 2011 from 234 registries. After comprehensive quality＇ evaluation, data from 177 registries have been selected as sources of the reports reflecting cancer incidence and mortaliD, in the registration areas in 2011. These reports are the updated cancer statistics so far, covering much more registries and a hig population.
基金supported in part by the National Natural Science Foundation of China(61301228,61371091)the Fundamental Research Funds for the Central Universities(3132014212)
文摘This paper is mainly to deal with the problem of direction of arrival(DOA) estimations of multiple narrow-band sources impinging on a uniform linear array under impulsive noise environments. By modeling the impulsive noise as α-stable distribution, new methods which combine the sparse signal representation technique and fractional lower order statistics theory are proposed. In the new algorithms, the fractional lower order statistics vectors of the array output signal are sparsely represented on an overcomplete basis and the DOAs can be effectively estimated by searching the sparsest coefficients. To enhance the robustness performance of the proposed algorithms,the improved algorithms are advanced by eliminating the fractional lower order statistics of the noise from the fractional lower order statistics vector of the array output through a linear transformation. Simulation results have shown the effectiveness of the proposed methods for a wide range of highly impulsive environments.
基金supports from National Natural Science Foundation of China (No. 41406032 and No. 41376014)Open Fund of State Key Laboratory of Satellite Ocean Environment Dynamics (No. SOED1305)
文摘Ocean waves are the core environmental elements affecting the movements and structure design of ships. Statistical analysis of wave parameters is the basis for the establishment of long-term ship environmental adaptability prediction model. The observations from coastal stations, buoys, altimeters and volunteer ships that cover from 1993 to 2011 were interpolated into miller Ion-lat grids by using bilinear method and the analytical fields of ocean waves were given. By using optimal interpolation, the analysis wave fields were assimilated into the WAVEWATCH III （WW3） simulation results. From the assimilated results, the wave rose statistics, the wave height of muitiyear return period and the extreme 2-D wave spectrum are related to the ship seakeeping were calculated. Finally, the wave statistics in China offshore were analyzed in detail.
文摘This paper focuses on a method to solve structural optimization problems using particle swarm optimization （PSO）, surrogate models and Bayesian statistics. PSO is a random/stochastic search algorithm designed to find the global optimum. However, PSO needs many evaluations compared to gradient-based optimization. This means PSO increases the analysis costs of structural optimization. One of the methods to reduce computing costs in stochastic optimization is to use approximation techniques. In this work, surrogate models are used, including the response surface method （RSM） and Kriging. When surrogate models are used, there are some errors between exact values and approximated values. These errors decrease the reliability of the optimum values and discard the realistic approximation of using surrogate models. In this paper, Bayesian statistics is used to obtain more reliable results. To verify and confirm the efficiency of the proposed method using surrogate models and Bayesian statistics for stochastic structural optimization, two numerical examples are optimized, and the optimization of a hub sleeve is demonstrated as a practical problem.
基金supported by Geological Survey of Canada and China University of Geosciences (Wuhan)
文摘The relationship between fractal point pattern modeling and statistical methods of pa- rameter estimation in point-process modeling is reviewed. Statistical estimation of the cluster fractal dimension by using Ripley＇s K-function has advantages in comparison with the more commonly used methods of box-counting and cluster fractal dimension estimation because it corrects for edge effects, not only for rectangular study areas but also for study areas with curved boundaries determined by re- gional geology. Application of box-counting to estimate the fractal dimension of point patterns has the disadvantage that, in general, it is subject to relatively strong ＂roll-off＂ effects for smaller boxes. Point patterns used for example in this paper are mainly for gold deposits in the Abitibi volcanic belt on the Canadian Shield. Additionally, it is proposed that, worldwide, the local point patterns of podiform Cr, volcanogenic massive sulphide and porphyry copper deposits, which are spatially distributed within irregularly shaped favorable tracts, satisfy the fractal clustering model with similar fractal dimensions. The problem of deposit size （metal tonnage） is also considered. Several examples are provided of cases in which the Pareto distribution provides good results for the largest deposits in metal size-frequency distribution modeling.
基金supported by the Major Program of National Natural Science Foundation of China (10990012)the National Natural Science Foundation of China (61201296,61271024)+1 种基金the Fundamental Research Funds for the Central Universities (K5051202037)Guangxi Key Lab of Wireless Wideband Communication & Signal Processing (12205)
文摘The problem of two order statistics detection schemes for the detection of a spatially distributed target in white Gaussian noise are studied.When the number of strong scattering cells is known,we first show an optimal detector,which requires many processing channels.The structure of such optimal detector is complex.Therefore,a simpler quasi-optimal detector is then introduced.The quasi-optimal detector,called the strong scattering cells’ number dependent order statistics（SND-OS） detector,takes the form of an average of maximum strong scattering cells with a known number.If the number of strong scattering cells is unknown in real situation,the multi-channel order statistics（MC-OS） detector is used.In each channel,a various number of maximums scattered from target are averaged.Then,the false alarm probability analysis and thresholds sets for each channel are given,following the detection results presented by means of Monte Carlo simulation strategy based on simulated target model and three measured targets.In particular,the theoretical analysis and simulation results highlight that the MC-OS detector can efficiently detect range-spread targets in white Gaussian noise.
