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1.
采用定量分析和定性分析相结合的方法,对影响我国流动人口的因素进行分析。定量分析主要用于对社会经济因素的分析,通过相关分析、因子分析以及回归分析,发现全国31个省(市、区)流动人口与全省(市、区)GDP等11项社会经济因素指标因子有显著的正相关关系,与全省(市、区)第二产业占GDP比重等3项指标因子无显著关系,同时提取两个主成分代表所有的变量,得到流动人口与各变量之间的回归方程。此外,结合制度、信息、宗教文化对流动人口的影响进行简要定性分析,认为政府不仅要发展经济也要进一步完善制度、信息可获得性等方面的政策,从而更好地管理流动人口,构建社会主义和谐社会。  相似文献   

2.
为探讨环境因素对学生身高的影响,对30个城市2010年18岁汉族男女学生身高平均数与相应城市的海拔高度、地理纬度、经度和2010年前18年的年降水量、年平均气温、年平均湿度、年日照时间和年人均GDP等环境指标进行相关分析和主成分回归分析.结果显示:不同纬度、经度地区的城市18岁汉族学生身高的差异明显;除海拔高度外,另7项环境指标与学生身高具有相关关系,但环境指标间相关程度较高,独立性差,存在共线性问题;环境指标主成分分析提取了2个主成分,分别代表气象因素和社会经济因素;用其得分建立了与城市18岁男、女学生身高的主成分回归方程,并将其转换为与原环境指标之间的线性回归方程用于推测2010年和2005年18岁学生的身高,推测精度高.因此,身高与海拔高度无相关,与纬度、经度、年日照时间和年人均GDP呈正相关,与年降水量、年平均气温和年平均湿度呈负相关;若城市的这些环境指标已知,即可预测其学生的身高.  相似文献   

3.
运用实证分析的方法计算并分析了上市公司资本结构的影响因素,首先对选取的15个原始变量进行主成分分析,并计算出主成分得分;然后用主成分得分与资产负债率作多元回归分析;最后根据实证分析的结果进行了因素分析.结果表明:(1)短期偿债能力指标或者变现能力指标对资本结构的影响最大,且与资产负债率之间呈负相关关系;(2)企业规模与资产负债率呈正相关;(3)股权结构及企业的盈利能力与资产负债率呈负相关。  相似文献   

4.
为了研究织物结构参数与精纺面料抗皱性能的关系,在确定影响织物折皱回复性能的各个结构参数的基础上,应用动态回复角测试仪对21种精纺面料进行折皱回复角测试。为避免多元回归分析出现多重共线性问题,利用主成分分析方法对织物多个基本结构参数进行降维处理,得到4个互相独立的主成分。以主成分为自变量,分别取经向折皱回复角、纬向折皱回复角以及经纬向折皱回复角之和为因变量,采用回归分析的方法建立抗皱性与提取主成分的关系模型。结果表明:建立的主成分与折皱回复角之间的回归方程,达到非常显著的水平,对抗皱性能进行预测是可行的。通过主成分分析可知,主成分Z1,Z2,Z4是决定精纺面料抗皱性的主要因素。  相似文献   

5.
基于因子-主成分回归分析的股价技术分析研究   总被引:1,自引:0,他引:1  
介绍了回归分析中多元线性回归的理论及应用方法,并以股价技术指标为研究对象,利用spss统计分析软件,建立了短期股价变动的多元线性回归模型。同时讨论了被选为自变量的参数之间存在的多重共线性问题,并分析该问题对线性回归分析结果造成的影响。因子-主成分分析的核心是用较少的相互独立的因子反映原有变量的绝大部分信息。主成分分析的主要思想是:从自变量中提取出新的变量,这些变量是原变量的适当线性组合,并且互不相关,因此应用SPSS软件进行数据缩减、提取主成分,并以主成分因子为新的自变量建立主成分回归方程,消除了多重共线性对回归模型的影响。最后对不同模型的测试结果进行了比较、分析,验证了因子-主成分分析在解决实际经济问题中的有效性。  相似文献   

6.
《河南科学》2016,(9):1567-1571
为了解陕西省城市低碳经济发展的情况和影响因素,选取陕西省7个具有代表性的城市,结合各城市低碳发展水平的现状,构建评价指标体系,利用主成分分析法对研究区低碳发展水平进行综合评价和分析.结果表明:西安市的低碳发展水平最高,综合得分为1.059 9;榆林市低碳发展水平较高,综合得分为0.580 5,其余几个城市低碳发展水平均较低.从各主成分分析得出工业"三废"的排放和能源的消耗会阻碍地区低碳发展水平的提高,而城市绿地覆盖率的提高会促进城市低碳的发展.建议通过加大节能减排、提高植被覆盖率等措施来提高城市的低碳发展水平.  相似文献   

7.
空气质量在国际上已是重点控制对象,利用主成分方法对影响各个城市的空气质量的指标进行分析,得出影响空气质量的主要因素.然后选取主成分进行费希尔(Fisher)判别分析,建立主成分的费希尔判别分析模型,对城市的空气质量进行判别,再利用判别式分别对重庆、成都、昆明、宝鸡4个城市的空气质量类别进行预测.  相似文献   

8.
运用主成分分析的方法对71个盐湖8个水化学特征变量进行研究计算,获得4个揭示水化学特征的主成分及相应的数学模型,从而解释8个水化学特征变量与盐湖类型之间的相关性信息.  相似文献   

9.
为解决高速公路路基沉降量难以获取的难题,提出一种基于主成分分析(principal compohent analysis,PCA)的相关向量机(relevance vector machine,RVM)路基沉降量预测方法。通过主成分分析法将多个易获取的土体常规物理参数降维成少数且独立的变量,借助相关向量机模型反映路基沉降量与4个主成分变量之间的非线性映射关系,建立基于PCA-RVM的高速公路路基沉降量预测模型。将该模型应用于工程实例,在同样学习样本情况下与4种神经网络预测模型对比分析,结果表明:PCA-RVM预测模型通过分析各因素的相关性与贡献率,将多个影响因素合理化为少数主成分变量,在信息筛选方面明显优于其余4种模型;各模型预测结果显示,在路基沉降量预测结果的相对误差及均方差方面,PCA-RVM预测模型均占据较大优势。PCA-RVM模型具有精度高、离散性小、可靠度高等优点,为高速公路路基沉降量预测提供了一种新方法。  相似文献   

10.
《中国统计年鉴》依据历年来我国各省市的城镇居民收入数据,运用多元统计分析中的聚类分析和主成分分析构造理论模型,并利用SPSS统计分析软件来进行统计计算.通过估计模型参数和分析多个变量之间的观测的数据,以及我国城镇居民收入间存在的关系,得到了影响所存在问题的主要因素、各个因素之间的相关程度,根据所构造的模型计算了31个省市城镇居民的收入排名,并据此绘出了相关结论和建议.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

14.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

15.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

16.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

17.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

18.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

19.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

20.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

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