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基于相关系数的ID3优化算法 被引量:15
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作者 吴思博 陈志刚 黄瑞 《计算机工程与科学》 CSCD 北大核心 2016年第11期2342-2347,共6页
ID3算法是目前最具有影响力的一种决策树构造算法,但仍然有许多的缺点,例如在多值属性偏向方面的问题、计算时间复杂度高、效率不高等问题。提出了一种基于斯皮尔曼等级相关系数的ID3决策树构造优化算法,利用相关系数克服了ID3算法在多... ID3算法是目前最具有影响力的一种决策树构造算法,但仍然有许多的缺点,例如在多值属性偏向方面的问题、计算时间复杂度高、效率不高等问题。提出了一种基于斯皮尔曼等级相关系数的ID3决策树构造优化算法,利用相关系数克服了ID3算法在多值属性偏向方面的问题,在一定程度上提高了算法的分类准确率。利用相关数学知识对计算过程进行了化简,减少了ID3算法在log运算上的运行时间。最后通过实验验证了优化后的算法是可行的,且在准确率和运行速度方面都有更好的表现。 展开更多
关键词 决策树 ID3算法 信息熵 斯皮尔曼等级 相关系数
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Spatiotemporal variability of rain-on-snow events in the arid region of Northwest China
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作者 YANG Zhiwei CHEN Rensheng +3 位作者 LIU Zhangwen ZHAO Yanni LIU Yiwen WU Wentong 《Journal of Arid Land》 SCIE CSCD 2024年第4期483-499,共17页
Rain-on-snow(ROS)events involve rainfall on snow surfaces,and the occurrence of ROS events can exacerbate water scarcity and ecosystem vulnerability in the arid region of Northwest China(ARNC).In this study,using dail... Rain-on-snow(ROS)events involve rainfall on snow surfaces,and the occurrence of ROS events can exacerbate water scarcity and ecosystem vulnerability in the arid region of Northwest China(ARNC).In this study,using daily snow depth data and daily meteorological data from 68 meteorological stations provided by the China Meteorological Administration National Meteorological Information Centre,we investigated the spatiotemporal variability of ROS events in the ARNC from 1978 to 2015 and examined the factors affecting these events and possible changes of future ROS events in the ARNC.The results showed that ROS events in the ARNC mainly occurred from October to May of the following year and were largely distributed in the Qilian Mountains,Tianshan Mountains,Ili River Valley,Tacheng Prefecture,and Altay Prefecture,with the Ili River Valley,Tacheng City,and Altay Mountains exhibiting the most occurrences.Based on the intensity of ROS events,the areas with the highest risk of flooding resulting from ROS events in the ARNC were the Tianshan Mountains,Ili River Valley,Tacheng City,and Altay Mountains.The number and intensity of ROS events in the ARNC largely increased from 1978 to 2015,mainly influenced by air temperature and the number of rainfall days.However,due to the snowpack abundance in areas experiencing frequent ROS events in the ARNC,snowpack changes exerted slight impact on ROS events,which is a temporary phenomenon.Furthermore,elevation imposed lesser impact on ROS events in the ARNC than other factors.In the ARNC,the start time of rainfall and the end time of snowpack gradually advanced from the spring of the current year to the winter of the previous year,while the end time of rainfall and the start time of snowpack gradually delayed from autumn to winter.This may lead to more ROS events in winter in the future.These results could provide a sound basis for managing water resources and mitigating related disasters caused by ROS events in the ARNC. 展开更多
关键词 rain-on-snow events SNOWPACK SNOWMELT climate change spearman's rank correlation arid region of Northwest China
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元120长221 油藏注水见效及井间连通性研究 被引量:5
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作者 李成勇 罗璇宇 +2 位作者 伍勇 龚伟 张锦良 《新疆石油天然气》 CAS 2010年第2期55-58,64,共5页
油藏注水开采过程中,详细了解注采见效状况及井间连通性,对指导注水开发全过程,延长稳产时间,提高采收率等都具有重要的作用。本文用相关系数理论,通过相关度的大小来判断油田注水见效情况及井间连通性,取得了很好的效果。研究表明Spear... 油藏注水开采过程中,详细了解注采见效状况及井间连通性,对指导注水开发全过程,延长稳产时间,提高采收率等都具有重要的作用。本文用相关系数理论,通过相关度的大小来判断油田注水见效情况及井间连通性,取得了很好的效果。研究表明Spearman秩相关系数能分析注水见效及井间连通性,本文的研究对油田开发具有重要的指导意义。 展开更多
关键词 注水开采 注水见效 井间连通性 spearman 相关系数
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基于Logistic回归的古代玻璃制品化学成分分析和研究
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作者 孙浩东 《电脑迷》 2023年第1期19-21,共3页
文章主要通过研究玻璃含有的不同化学成分,分析和鉴别古代的玻璃制品。首先分析了现有玻璃文物的数据,利用Spearman’s rank correlation coefficient和卡方检验表面分化、纹饰、颜色和玻璃类型之间的联系,采用Logistic回归鉴别未知文物... 文章主要通过研究玻璃含有的不同化学成分,分析和鉴别古代的玻璃制品。首先分析了现有玻璃文物的数据,利用Spearman’s rank correlation coefficient和卡方检验表面分化、纹饰、颜色和玻璃类型之间的联系,采用Logistic回归鉴别未知文物,分析其所属的类型,并分析了分类结果的灵敏度。通过分析可知,文章采用的分类方法,能较好地通过化学成分对玻璃进行分类。 展开更多
关键词 spearman’s rank correlation coefficient 卡方检验 LOGISTIC回归
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Data quality evaluation and calibration of on-road remote sensing systems based on exhaust plumes
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作者 Shijie Liu Xinlu Zhang +3 位作者 Linlin Ma Liqiang He Shaojun Zhang Miaomiao Cheng 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2023年第1期317-326,共10页
In recent years,with rapid increases in the number of vehicles in China,the contribution of vehicle exhaust emissions to air pollution has become increasingly prominent.To achieve the precise control of emissions,on-r... In recent years,with rapid increases in the number of vehicles in China,the contribution of vehicle exhaust emissions to air pollution has become increasingly prominent.To achieve the precise control of emissions,on-road remote sensing(RS)technology has been developed and applied for law enforcement and supervision.However,data quality is still an existing issue affecting the development and application of RS.In this study,the RS data from a cross-road RS system used at a single site(from 2012 to 2015)were collected,the data screening process was reviewed,the issues with data quality were summarized,a new method of data screening and calibration was proposed,and the effectiveness of the improved data quality control methods was finally evaluated.The results showed that this method reduces the skewness and kurtosis of the data distribution by up to nearly 67%,which restores the actual characteristics of exhaust diffusion and is conducive to the identification of actual clean and high-emission vehicles.The annual variability of emission factors of nitric oxide decreases by 60%-on average-eliminating the annual drift of fleet emissions and improving data reliability. 展开更多
关键词 On-road remote sensing(RS) Data quality spearman rank correlation Least-square regression with a non-zero intercept Cook value
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Identification of abnormal conditions in high-dimensional chemical process based on feature selection and deep learning 被引量:4
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作者 Wende Tian Zijian Liu +2 位作者 Lening Li Shifa Zhang Chuankun Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2020年第7期1875-1883,共9页
Identification of abnormal conditions is essential in the chemical process.With the rapid development of artificial intelligence technology,deep learning has attracted a lot of attention as a promising fault identific... Identification of abnormal conditions is essential in the chemical process.With the rapid development of artificial intelligence technology,deep learning has attracted a lot of attention as a promising fault identification method in chemical process recently.In the high-dimensional data identification using deep neural networks,problems such as insufficient data and missing data,measurement noise,redundant variables,and high coupling of data are often encountered.To tackle these problems,a feature based deep belief networks(DBN)method is proposed in this paper.First,a generative adversarial network(GAN)is used to reconstruct the random and non-random missing data of chemical process.Second,the feature variables are selected by Spearman’s rank correlation coefficient(SRCC)from high-dimensional data to eliminate the noise and redundant variables and,as a consequence,compress data dimension of chemical process.Finally,the feature filtered data is deeply abstracted,learned and tuned by DBN for multi-case fault identification.The application in the Tennessee Eastman(TE)process demonstrates the fast convergence and high accuracy of this proposal in identifying abnormal conditions for chemical process,compared with the traditional fault identification algorithms. 展开更多
关键词 Chemical process Deep Belief Networks Fault identification Generative Adversarial Networks spearman rank Correlation
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Change Trend of Chinese Urban Residents' Food-nitrogen Consumption 被引量:2
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作者 王俊能 许振成 彭晓春 《Agricultural Science & Technology》 CAS 2010年第4期176-179,共4页
Change trend of Chinese urban residents' per capita food-nitrogen annual consumption from 1981 to 2007 was analyzed and predicted by using ARIMA time-series model in order to reveal the change of urban food-nitrogen ... Change trend of Chinese urban residents' per capita food-nitrogen annual consumption from 1981 to 2007 was analyzed and predicted by using ARIMA time-series model in order to reveal the change of urban food-nitrogen consumption during the China's urbanization process.Results showed that after 1980s,the annual consumption of Chinese urban residents' food-nitrogen had a change trend of " increase-decrease-increase" and generally presented as a slight increasing trend;With the acceleration of rapid economic development and urbanization process,Chinese urban residents' food-nitrogen consumption will still keep a rising trend in future,and also has a large rising space. 展开更多
关键词 Food consumption NITROGEN spearman's rank correlation coefficient ARIMA model Urban residents China
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Guided Wave Based Damage Detection Method for Aircraft Composite Structures under Varying Temperatures 被引量:2
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作者 Dongyue Gao Yunlong Ma +2 位作者 Zhanjun Wu Yuebin Zheng Hongbo Lu 《Structural Durability & Health Monitoring》 EI 2021年第1期23-37,共15页
Guided waves based damage detection methods using base signals offer the advantages of simplicity of signal generation and reception,sensitivity to damage,and large area coverage;however,applications of the technology... Guided waves based damage detection methods using base signals offer the advantages of simplicity of signal generation and reception,sensitivity to damage,and large area coverage;however,applications of the technology are limited by the sensitivity to environmental temperature variations.In this paper,a Spearman Damage Index-based damage diagnosis method for structural health condition monitoring under varying temperatures is presented.First,a PZT sensor-based Guided wave propagation model is proposed and employed to analyze the temperature effect.The result of the analysis shows the wave speed of the Guided wave signal has higher temperature sensitivity than the signal fluctuation features.Then,a Spearman rank correlation coefficient-based damage index is presented to identify damage of the structure under varying temperatures.Finally,a damage detection test on a composite plate is conducted to verify the effectiveness of the Spearman Damage Index-based damage diagnosis method.Experimental results show that the proposed damage diagnosis method is capable of detecting the existence of the damage and identify its location under varying temperatures. 展开更多
关键词 Structure health monitoring Guided wave temperature effect spearman rank correlation coefficient damage index
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住房租赁市场租金价格影响因素分析及趋势预测——以广州市为例 被引量:2
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作者 何成忠 《时代金融》 2020年第1期58-62,共5页
本文以广州市为例,通过SpearmanRank相关性分析,实证得出引起租赁价格上涨幅度的最主要因素是一二手房价的上涨程度、以及人均可支配收入的增长程度,即房价和收入是影响租金上涨的最主要因素。为探索数据内生相关性,本文使用ARIMA模型... 本文以广州市为例,通过SpearmanRank相关性分析,实证得出引起租赁价格上涨幅度的最主要因素是一二手房价的上涨程度、以及人均可支配收入的增长程度,即房价和收入是影响租金上涨的最主要因素。为探索数据内生相关性,本文使用ARIMA模型分别对租赁价格指数(HRPI)和常住人口(RP)进行分析并建立模型方程,根据模型预测,2019年11月的住房租赁价格指数为2253,较10月下降2;2019年广州常住人口数将达到1536万人,较2018年增加46万人。最后提出了加强住房租赁市场制度顶层设计,鼓励金融机构参与拓展租赁市场资金渠道等政策建议。 展开更多
关键词 住房租赁 相关性 线性回归 spearman rank ARIMA模型
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Characteristics of Ambient Air Quality in the Central Urban Area of Western Guizhou in the Past Five Years 被引量:1
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作者 Shihua JIANG Zaixiang CHI +3 位作者 Kai XU Lijuan LIU Zijiang YANG Changwen CHEN 《Meteorological and Environmental Research》 CAS 2020年第6期23-30,共8页
Air is an important condition for human activities and survival,and its quality is closely related to the quality of life and level of health for the people.In recent years,the problem caused by air quality has become... Air is an important condition for human activities and survival,and its quality is closely related to the quality of life and level of health for the people.In recent years,the problem caused by air quality has become one of the main problems that endanger human health and restrict economic development,which has been widely concerned.In this paper,the air quality status and its changing trend were analyzed by using the methods of the comprehensive index of ambient air quality and Spearman s rank correlation coefficient,based on the hourly pollutant concentration data of five national ambient air quality monitoring stations in the central urban area of Liupanshui City,Guizhou Province from January 1,2015 to December 31,2019.The results showed that the concentration of air pollutants in the atmosphere in the past five years showed a downward trend in the central urban area of Liupanshui City.During 2018-2019,the air quality has been up to the standard for two consecutive years,and it was developing to a higher quality direction.The air quality was better in summer half year than in winter half year.In one year,the air quality was the best in June and the worst in February.The air quality was the best at 07:00 and the worst at 21:00 every day.The air quality in the east and the west of the city was better than that in the middle.In most years,the activities,making and burning paper to resemble money as an offering sacrifices to gods or ancestors in Zhongyuan Festival,caused serious pollution. 展开更多
关键词 Air quality Pollution concentration spearman s rank correlation coefficient Change trends
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Spatio-temporal Distribution Characteristics and Environmental Impact Factors of Lung Cancer Mortality: A Case Study of Yuhui District in Bengbu City, China
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作者 TANG Jingjing GU Kangkang +4 位作者 MI Jing ZHANG Wenhao FANG Yunhao LI Yuwei WANG Beichen 《Chinese Geographical Science》 SCIE CSCD 2022年第5期867-882,共16页
Among cancers, lung cancer is the most common cause of death in China. For the prevention and control of lung cancer, it is necessary to investigate the spatial and temporal distribution of lung cancer mortality, as w... Among cancers, lung cancer is the most common cause of death in China. For the prevention and control of lung cancer, it is necessary to investigate the spatial and temporal distribution of lung cancer mortality, as well as the changes in the trend and the affecting mechanism. Based on statistics and auto-correlation analysis, this paper studied the spatial and temporal distribution of lung cancer mortality in Yuhui District, Bengbu, Huaihe River Basin, from 2017 to 2020. In addition, Spearman’s Rank Correlation Assessment Model and Geographic Detector Model were used to examine the relationship between environmental factors and lung cancer mortality to identify impact factors and their mechanisms. The findings indicated that: 1) from the characteristics of temporal distribution, the number of lung cancer deaths exhibited a linear growth tendency, with the highest mortality in winter;2) from the characteristics of spatial distribution, lung cancer mortality showed a strong spatial agglomeration form, concentrating on two clustering areas, located in the old city and the central city of Bengbu, near the Huaihe River;3) from the point of view of the whole research area, there were 15 impact factors with significant correlation in the built and natural environment factors. The significant impacting factors in the built environment included land use, road traffic, spatial form and blue-green space, which could indirectly affect lung cancer mortality, while air pollution and temperature constituted the significant impacting factors in the natural environment;4) the influence of screened environmental factors on lung cancer mortality was different. Spatial stratified heterogeneity assessment, the interaction among environmental factors demonstrated statistical significance, it was found that the interaction between environmental factors in pairs had a significant enhancement effect on lung cancer mortality. To some extent, urban planning and policies could reduce lung cancer mortality. 展开更多
关键词 lung cancer mortality built environment spatial auto-correlation spearman’s rank Correlation Geographic Detector Model Bengbu City China
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App Store Analysis: Using Regression Model for App Downloads Prediction
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作者 Shanshan Wang Wenjun Wu Xuan Zhou 《国际计算机前沿大会会议论文集》 2016年第1期54-56,共3页
App store provides rich information for software vendors and customers to understand the market of mobile applications. However, app store analysis don’t consider some vital factors such as version number, app descri... App store provides rich information for software vendors and customers to understand the market of mobile applications. However, app store analysis don’t consider some vital factors such as version number, app description and app name currently. In this paper we propose an approach that App Store Analysis can be used to predict app downloads. We use data mining to extract app name and description and app rank information etc. from the Wandoujia App Store and AppCha App Store. We use questionnaire and sentimentanalysis to quantify some app nonnumeric information. We revealed strong correlations app name score, app rank, app rating with app downloads by Spearman’s rank correlation analysis respectively. Finally, we establish a multiple nonlinear regression model which app downloads defined as dependent variable and three relevant attributes defined as independent variable. On average, 59.28 % of apps in Wandoujia App Store and 66.68 % of apps in AppCha App Store can be predicted accurately within threshold which error rate is 25 %. One can observe the more detailed classification of app store, the more accurate for regression modeling to predict app downloads. Our approach can help app developers to notice and optimize the vital factors which influence app downloads. 展开更多
关键词 APP STORE spearman’s rank CORRELATION ANALYSIS Regression ANALYSIS Regression model APP downloads PREDICTION
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An Automatic Monitoring and Alarming Method for the Power Supply of Weather Radars
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作者 Shihua JIANG Ruyong LONG +3 位作者 Changwen CHEN Lijuan LIU Kun ZHAO Liang HOU 《Meteorological and Environmental Research》 CAS 2021年第2期23-25,29,共4页
As weather radar stations require headroom environment to operate,they were mostly built on highlands which are usually unattended.The mains supply is relatively poor,and the risk of radar stoppages due to power outag... As weather radar stations require headroom environment to operate,they were mostly built on highlands which are usually unattended.The mains supply is relatively poor,and the risk of radar stoppages due to power outage is therefore ever-present.As such,the radar construction program is used to build a complementary security video monitoring system.By collecting monitoring images of the regulated power supply in real-time from power supply auto transfer systems in distribution rooms and radar transceiver rooms,using Spearman’s rank correlation coefficient to analyse pixel variation trends,and supplementing statistical analysis of pixel characteristics difference to eliminate misjudgments resulting from low image contrast in special scenarios,a software can be developed through C#.It has the function of automatically monitoring mains supply and alerting staff on duty to handle the power outage in a timely manner via text message so that any potential risk is neutralised before it can cause damage.This monitoring and auto-alerting approach is generally applicable to unattended rooms with large amounts of electronical equipment. 展开更多
关键词 Weather radar spearman’s rank correlation coefficient Power supply MONITOR ALARM
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Projecting impact of CPEC on Pakistan’s electric power crisis
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作者 Sumera Iqbal Jianxun Chu Shafei Moiz Hali 《Chinese Journal of Population,Resources and Environment》 2019年第4期310-321,共12页
The commencement of China–Pakistan Economic Corridor has led to the appreciation of Pakistan’s economic outlook from 5.4%to 5.8%by the World Bank.The upgraded outlook is a welcome sign but it is still trivial,essent... The commencement of China–Pakistan Economic Corridor has led to the appreciation of Pakistan’s economic outlook from 5.4%to 5.8%by the World Bank.The upgraded outlook is a welcome sign but it is still trivial,essentially attributable to the electric power crisis,which approximately trims 2%of Pakistan’s economic growth annually.Almost 60%of the CPEC(China–Pakistan Economic Corridor)funds are directed at Pakistan’s energy sector,hence,demanding careful attention of both researchers and policy analysts alike.The study is based upon a meta-analytic review of literature concerning CPEC and Pakistan’s energy sector.The results of the study demonstrate that CPEC is an easing agent for Pakistan’s energy crisis(82.30%).The results also highlight points of concern,including inadequate planning(47%),dilapidated electricity distribution system causing losses(64.7%),and an unsustainable energy mix(64.7%).The study further validates the findings via Spearman’s Rho-Correlation.The rρvalue for the possible“resolution of Pakistan’s energy crisis”is 0.5426 achieving a significance level of 98%and a corresponding p-value of 0.0252.The significant negative rρvalue attained is−0.4894 which establishes the fact that lack of planning can hinder the energy crisis resolution. 展开更多
关键词 CPEC FDI power crisis transmission losses energy crisis sustainable-energy mix spearman’s rank correlation
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山西翅果油树群落种间关系的数量分析 被引量:122
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作者 张峰 上官铁梁 《植物生态学报》 CAS CSCD 北大核心 2000年第3期351-355,共5页
应用 2× 2列联表的 Fisher精确检验、Pearson相关系数和 Spearm an秩相关系数检验研究了山西翅果油树群落的种间关系 ,分别测定了 42种植物 ,共 86 1个种对的种间关联 (或相关 )。结果表明 :1) 2× 2列联表的精确检验共有 2 8... 应用 2× 2列联表的 Fisher精确检验、Pearson相关系数和 Spearm an秩相关系数检验研究了山西翅果油树群落的种间关系 ,分别测定了 42种植物 ,共 86 1个种对的种间关联 (或相关 )。结果表明 :1) 2× 2列联表的精确检验共有 2 8个种对为正关联 ,14个种对为负关联 (p <0 .0 5或 p<0 .0 1,下同 ) ;Peaorson相关系数有 5 6个种对为正相关 ,14个种对为负相关 ;Spearman秩相关系数有 96个种对呈正相关 ,46个种对呈负相关。 2 ) 2× 2列联表的Fisher精确检验不能反映两个种对间的数量变化关系 ,应用 Pearson相关系数和 Spearman秩相关检验来刻划种对间的数量变化关系 ;与 Pearson相关系数检验相比 ,Spearman秩相关系数检验具有较高的灵敏度。 3)种对间的正关联和正相关 ,主要是由于它们具有相近的生物学特性 ,对生境具有相似的生态适应性和相互分离的生态位所致 ;而种对间的负关联和负相关 ,则主要是由于它们具有不同的生物学特性 ,对生境具有不同的生态适应性和相互重叠的生态位所致。 展开更多
关键词 翅果油树群落 种间关系 关联分析 数量分析
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改进Copula对数据拟合的方法 被引量:35
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作者 史道济 姚庆祝 《系统工程理论与实践》 EI CSCD 北大核心 2004年第4期49-55,共7页
 给出相关结构Copula、秩相关系数Spearmanρ与Kendallτ和尾部相关系数η,以及这三个关联性度量与Copula之间的关系,各个相关系数的估计方法.在一个Copula族内进行适当变换,得到新的Copula,使得能更好地拟合样本的各个相关系数.最后,...  给出相关结构Copula、秩相关系数Spearmanρ与Kendallτ和尾部相关系数η,以及这三个关联性度量与Copula之间的关系,各个相关系数的估计方法.在一个Copula族内进行适当变换,得到新的Copula,使得能更好地拟合样本的各个相关系数.最后,以沪、深日收盘综合指数为例,讨论了二个股市波动率的相关性,建立了一个较好的数学模型. 展开更多
关键词 相关结构 COPULA 秩相关系数 spearman ρ Kendall τ 尾部相关系数η
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耕地多功能权衡与协同时空格局的动态分析——以湖北省为例 被引量:75
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作者 朱庆莹 胡伟艳 赵志尚 《经济地理》 CSSCI CSCD 北大核心 2018年第7期143-153,共11页
以湖北省为例,利用2000、2005、2010和2013年的社会经济、土壤和气象等数据,运用Spearman秩相关和空间自相关方法分析揭示耕地多功能权衡与协同的时空格局及变化规律。结果显示:(1)物质产出、净固碳、景观美学功能一直处于增加态势,其... 以湖北省为例,利用2000、2005、2010和2013年的社会经济、土壤和气象等数据,运用Spearman秩相关和空间自相关方法分析揭示耕地多功能权衡与协同的时空格局及变化规律。结果显示:(1)物质产出、净固碳、景观美学功能一直处于增加态势,其中物质产出功能增长较快,景观美学功能增长较慢;水源涵养功能变化平稳,劳动力承载功能不断减弱。(2)耕地功能之间主要表现为协同关系;随时间推移,部分功能之间由协同转为权衡,并且协同程度逐渐减弱而权衡程度逐步增强。(3)空间尺度上,相同耕地功能的协同类型多以'组团'形式出现,聚集性较强,权衡类型无明显聚集区域,大多零星分布在协同类型的周围,水源涵养和景观美学功能的权衡与协同格局比较稳定,剩余三种功能均发生不同程度变化;不同耕地功能之间的协同类型既有明显的'组团区',又有零星分布区,权衡类型也有类似特点,其中,净固碳与水源涵养、物质产出与景观美学、物质产出与水源涵养、景观美学与水源涵养的权衡与协同格局随时间推移较稳定,其余功能之间权衡与协同格局发生不同程度变化。研究认为,在改善耕地本底质量,合理引导劳动力流向和发展观光农业的同时,应加强县域内各部门之间以及县际之间的合作,科学划定耕地保护与利用区;共同促进耕地多功能的协同利用,增强耕地多功能的总体效益。 展开更多
关键词 耕地多功能 权衡与协同 生态功能 景观美学功能 spearman秩相关 空间自相关 湖北省
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山西绵山植被木本植物优势种群种间关联 被引量:56
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作者 张桂萍 张峰 茹文明 《生态学杂志》 CAS CSCD 北大核心 2006年第3期295-298,共4页
采用2×2列联表的χ2检验、Pearson相关系数和Spearman秩相关系数检验,研究了山西绵山植被21个优势种群、210个种对间的种间关联性。结果表明:1)χ2检验有109个种对呈正相关,101个种对呈负相关,正负关联比为1.08;Pearson相关系数检... 采用2×2列联表的χ2检验、Pearson相关系数和Spearman秩相关系数检验,研究了山西绵山植被21个优势种群、210个种对间的种间关联性。结果表明:1)χ2检验有109个种对呈正相关,101个种对呈负相关,正负关联比为1.08;Pearson相关系数检验87个种对正相关,122个种对呈负相关,正负关联比为0.71;Spearman秩相关系数检验99个种对呈正相关,111个种对呈负相关,正负关联比为0.89。2)按照21个优势种对环境的适应方式和主导生态因素,它们被划分为两大生态种组。3)与Pearson相关系数检验相比,Spearman秩相关系数检验具有较高的灵敏度。4)种对间的正关联或正相关,主要是由于它们具有相近的生物学特性,对生境具有相似的生态适应性和相互重叠的生态位所致;而种对间的负关联或负相关,则主要是由于它们具有不同的生物学特性,对生境具有不同的生态适应性和相互分离的生态位所致。 展开更多
关键词 绵山 种间关联 2×2列联表 Χ^2检验 Pearson相关系数 spearman秩相关系数
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Spearman秩相关系数的批量计算 被引量:62
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作者 万黎 毛炳启 《环境保护科学》 CAS 2008年第5期53-55,72,共4页
介绍了采用Visual FoxPro计算机语言对环境质量多时段监测数据计算Spearman秩相关系数的方法,用评价指标与时间序列间的相关性分析,并检验相关系数的显著性意义,进行环境质量变化趋势的评价;给出了实例和源程序。
关键词 spearman秩相关系数 变化趋势 VFP
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基于主成分分析的spearman秩相关系数法在长江干流水质分析中的应用 被引量:58
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作者 杨盼 卢路 +1 位作者 王继保 陈和春 《环境工程》 CAS CSCD 北大核心 2019年第8期76-80,共5页
基于长江干流宜宾、寸滩、宜昌、汉口、大通和上海(古洞口) 6个断面2005-2016年的高锰酸盐指数、五日生化需氧量、氨氮和总磷4项指标的监测数据,采用主成分分析法提取所有主成分,计算得到包含所有水质指标信息的综合得分值,再通过spear... 基于长江干流宜宾、寸滩、宜昌、汉口、大通和上海(古洞口) 6个断面2005-2016年的高锰酸盐指数、五日生化需氧量、氨氮和总磷4项指标的监测数据,采用主成分分析法提取所有主成分,计算得到包含所有水质指标信息的综合得分值,再通过spearman秩相关系数法分析主成分综合得分值的变化趋势。结果表明:长江干流上游水质优于中下游,上游水质呈变好的趋势,中下游水质表现出不断恶化的趋势。 展开更多
关键词 主成分分析法 spearman秩相关系数法 水质评价 长江干流
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