新股发行制度改革前后定价效率的实证分析

2009年5月份中国证监会启动新一轮股票发行制度改革,一年来先后有两百多家公司在A股市场成功上市。在新的发行体制下,一方面新股抑价程度有所降低,另一方面高市盈率发行、破发、超募等问题突出显现,人们关于此轮改革的成效存在广泛争议。采用主成分分析和多元回归分析的方法,运用相对价值判断标准对改革前后新股发行定价效率进行比较分析。结果显示,尽管发行体制改革后发行价高企,但是能够更好地反映公司的内在价值,发行价存在合理性基础。

基于发布阅读点赞的高校官网微信内容影响力评价——以华东师范大学为例

本文运用主成分分析及其MATLAB实现,来研究高校官网微信公众平台信息内容影响力的评价问题。从而为其提高运营绩效,找出了优势发布内容和有待加强的内容方面,同时为适合官网微信特点的信息内容的划分、采编等提供了技术支持。

Comparison between PCA and KPCA methods in comprehensive evaluation of robotic kinematic dexterity

Due to the correlation and diversity of robotic kinematic dexterity indexes, the principal component analysis （PCA） and kernel principal component analysis （KPCA） based on linear dimension reduction and nonlinear dimension reduction principle could be respectively introduced into comprehensive kinematic dexterity performance evaluation of space 3R robot of different tasks. By comparing different dimension reduction effects, the KPCA method could deal more effectively with the nonlinear relationship among different single kinematic dexterity indexes, and its calculation result is more reasonable for containing more comprehensive information. KPCA＇ s calculation provides scientific basis for optimum order of robotic tasks, and furthermore a new optimization method for robotic task selection is proposed based on various performance indexes.

Evaluation of the Rural Human Settlement in Shandong Province

Taking Shandong Province as the research object,this paper uses the principal component analysis method to evaluate the status of the rural human settlement in Shandong Province.It establishes the evaluation index system of the rural residential environment in Shandong Province,including living environment,economy,infrastructure,public service facilities,and ecological environment,in total five comprehensive index,and 20 secondary indexes.Through measurement and sorting of rural human environment development level of Shandong Province in 2010,the 17 cities are divided into-excellent,good,ordinary,poor-four development areas and are analyzed based on the restriction factor in the development of the region.

Real-time lane departure warning system based on principal component analysis of grayscale distribution and risk evaluation model

A technology for unintended lane departure warning was proposed. As crucial information, lane boundaries were detected based on principal component analysis of grayscale distribution in search bars of given number and then each search bar was tracked using Kalman filter between frames. The lane detection performance was evaluated and demonstrated in ways of receiver operating characteristic, dice similarity coefficient and real-time performance. For lane departure detection, a lane departure risk evaluation model based on lasting time and frequency was effectively executed on the ARM-based platform. Experimental results indicate that the algorithm generates satisfactory lane detection results under different traffic and lighting conditions, and the proposed warning mechanism sends effective warning signals, avoiding most false warning.

Application of Principal Component Analysis with SPSS in Water Quality Assessment of Shenzhen Eastern Beach

Survey and analysis were conducted on water quality of offshore seas in eastern region of Shenzhen by principal component analysis with SPSS. Then, 8 pollutants indices were then reduced to 5. Based on weighted analysis of principal component weights, comprehensive scores of different monitored stations were com- puted and sequenced in order to make evaluation on sea quality of eastern region of Shenzhen.

Assessment of temporal and spatial variations in surface water quality using multivariate statistical techniques: A case study of Nenjiang River basin, China

Assessment of temporal and spatial variations in surface water quality is important to evaluate the health of a watershed and make necessary management decisions to control current and future pollution of receiving water bodies. In this work, surface water quality data for 12 physical and chemical parameters collected from 10 sampling sites in the Nenjiang River basin during the years(2012-2013) were analyzed. The results show that river water quality has significant temporal and spatial variations. Hierarchical cluster analysis(HCA) grouped 12 months into three periods(LF, MF and HF) and classified 10 monitoring sites into three regions(LP, MP and HP) based on the similarity of water quality characteristics. The principle component analysis(PCA)/factor analysis(FA) was used to recognize the factors or origins responsible for temporal and spatial water quality variations. Temporal and spatial PCA/FA revealed that the Nenjiang River water chemistry was strongly affected by rock/water interaction, hydrologic processes and anthropogenic activities. This work demonstrates that the application of HCA and PCA/FA has achieved meaningful classification based on temporal and spatial criteria.

Study on GC-MS fingerprint of petroleum ether fraction of Shenqi Jiangtang Granules

Objective To establish gas chromatography-mass spectrometry(GC-MS)fingerprint method for the petroleum ether fraction of Shenqi Jiangtang Granules(SQJTG)and evaluate the product quality.Methods The GC-MS fingerprint of petroleum ether fraction of SQJTG was established by GC-MS,and the chemical components corresponding to the fingerprint peaks were structurally identified on NIST2014.The batch consistency of SQJTG products was evaluated based on the chemical composition of petroleum ether parts by using fingerprint similarity evaluation and Principal components analysis(PCA)technology.At the same time,Hotelling's T2 and DMODX statistics are used to set the control range for the quality of different batches of products.Results Twenty-two components were identified from the petroleum ether part of SQJTG,accounting for 60.94%of the total components separated.The similarity of fingerprints of petroleum ether parts of 24 batches of SQJTG was greater than 0.95.The PCA of 24 batches of samples were all under the control limits of Hotellin’s T2 and DMODX statistics,indicating that the petroleum ether parts of different batches of SQJTG were consistent.Conclusion The developed GC-MS fingerprint method can be used to evaluate the quality of SQJTG.

Comprehensive Appraisal of Provincial Low Carbon Development:A Case Study of China

In this research,the Factor Analysis model of measuring provincial low carbon development in China has been constructed.Based on data from 30 provinces,an empirical study was developed to measure comprehensive low carbon development using the Factor Analysis model(Principal Components method and Normalized Varimax Rotation).The results reveal that the provincial marks of low carbon development are generally low and only nine provinces have high marks(more than 0.80).The results also show significant regional disparity.The provincial marks of the eastern region are higher than both the middle and western provinces of China's Mainland.All of the provinces with high marks(more than 0.90) are located in the eastern region,and those with the lowest marks(0.60) are located in the middle region.Furthermore,regional disparity in low carbon development follows the same pattern as economic development in China.Finally,some suggestions for decision-makers are presented.

Application of principal component analysis to evaluation of black soil degradation in Jilin

Principal Component Analysis(PCA) can simplify the structure of database by replacing multi-dimensional parameters with relatively less comprehensive variables in order to ensure the minimum lost in initial data.In this paper,eighteen black soil samples from different sites were tested and thirteen distinctive indexes were chosen to evaluate the degeneration of black soil.By using principal component analysis,variables of thirteen dimensions can be diminished to six unrelated principal indexes.Analysis shows that the soluble salt content,Fulvic acids(FA) and aggregation degree have a high weighing coefficient,indicating these three indexes are the major parts for the evaluation of black soil degradation.It also provides a new path to the degenerated black soil treatment in Northeast China.

Comprehensive Evaluation of Sichuan Province Logistics Ability Based On Principal Component Analysis

Regional economy is the foundation for the development of the regional logistics and regional logistics as the support of the regional economic development, both interdependence, coordinated development, become the important factor of regional economic sus-tained and rapid development. This article selects relevant statistical data from 2002 to 2011 in Sichuan province were analyzed, and the quantitative mathematical model was established based on principal component analysis （pca）, and through the model for comprehensive evaluation of regional logistics caoability of Sichuan orovince.

Evaluation Model Construction of Peak Sweet Processing Suitability of Different Varieties of Chestnut

[Objective] The aims was to construct peak sweet processing suitability evaluation model and determine the suitable varieties of peak sweet processing in chestnut. [Method] ＂Zaofeng＂, ＂Yah Long＂ etc. 15 chestnut varieties in Yan Shan area were taken as research objects and investigated the sensory, physicochemical nutrition and processing indexes. The correlation analysis, principal component analysis and cluster analysis were adopted to simplify and calculate the evaluation index, and set up the mathematical model. [Result] Obvious differences in different varieties of raw materials and products of each index and some indicators existed significant correlation relationship; principal component analysis determined the five principal components： hardness, b value, moisture content, total sugar, browning degree and edible rate or the core indicators of quality evaluation in peak sweet chestnut, and the establishment of products comprehensive value scoring model： Y=0.033 509 hardness ＋0.033 509 b value ＋0.f85 1＇73 moisture content ＋0.208 983 total sugar ＋0.108 499 browning degree ＋0.430 327 ratio of feed, peak sweet chestnut quality and raw material associated model： Y=-1.109＋0.015 ratio of good fruit -0.018 kernel hardness ＋0.008 starch, [Conclusion] Peak sweet chestnut processing suitability evaluation model can provide the basis for chestnut processing and the suitable processing of the chestnut breeding; ＂Yanguang＂, ＂Yan Long＂, ＂Yankui＂, are very suitable, and ＂Zibo＂, ＂Yah Ping＂ are more appropriate for peak sweet processing.

Ecoagriculture evaluation of household level in red soil area of China

A hundred and twenty-one households in Yujiang county, Jiangxi province were investigated by adopting questionnaire method, and the evaluation system of index was established according to the integrative, hierarchical, scientific, practical, comparative and dynamic principles. The investigation data were firstly standardized and then processed with SPSS software. The index weight was confirmed by principal component analysis. Finally, the evaluation scale of ecoagriculture was calculated. The results showed that the evaluation value ranged from 0.141 to 0.689 for 121 households. Agricultural status of 113 households got the primary phase of ecoagriculture which accounting for 93.38%; 7 households into the second phase, representing 5.79% and only 1 household into the third phase according to the evaluation value. However, the ecoagriculture was divided into 5 stages, according to the evaluation value. Therefore, the ecoagriculture has huge potential to develop in red soil area, China.

Water Quality Evaluation Model Based on Principal Component Analysis and Information Entropy:Application in Jinshui River

水质评价对决策者决定水的使用功效尤为重要。水质综合评价系统中涉及到大量因子与指标,因子之间相互作用,致使水质的评价工作相对困难。主成分分析法可以消除因子间的相关性,因而被广泛应用于水质评价,但其忽略了数据离散程度的问题。熵值法则考虑了数据的离散特点。为更好地进行水质的综合评价,本文提出把主成分分析法和熵值法结合起来确定指标权重的方法,建立了水质评价模型,并采用该模型对郑州市金水河再生水2009年的水质情况进行评价,将评价结果与单独采用主成分分析或熵值法的结果进行了比较。结果表明了该方法的可行性与实用性,能够为非常规水资源利用提供理论依据和决策参考。