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Composition Analysis and Identification of Ancient Glass Products Based on L1 Regularization Logistic Regression
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作者 Yuqiao Zhou Xinyang Xu Wenjing Ma 《Applied Mathematics》 2024年第1期51-64,共14页
In view of the composition analysis and identification of ancient glass products, L1 regularization, K-Means cluster analysis, elbow rule and other methods were comprehensively used to build logical regression, cluste... In view of the composition analysis and identification of ancient glass products, L1 regularization, K-Means cluster analysis, elbow rule and other methods were comprehensively used to build logical regression, cluster analysis, hyper-parameter test and other models, and SPSS, Python and other tools were used to obtain the classification rules of glass products under different fluxes, sub classification under different chemical compositions, hyper-parameter K value test and rationality analysis. Research can provide theoretical support for the protection and restoration of ancient glass relics. 展开更多
关键词 Glass Composition L1 Regularization logistic regression Model K-Means Clustering analysis Elbow Rule Parameter Verification
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Comparison of dimension reduction-based logistic regression models for case-control genome-wide association study:principal components analysis vs.partial least squares 被引量:2
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作者 Honggang Yi Hongmei Wo +9 位作者 Yang Zhao Ruyang Zhang Junchen Dai Guangfu Jin Hongxia Ma Tangchun Wu Zhibin Hu Dongxin Lin Hongbing Shen Feng Chen 《The Journal of Biomedical Research》 CAS CSCD 2015年第4期298-307,共10页
With recent advances in biotechnology, genome-wide association study (GWAS) has been widely used to identify genetic variants that underlie human complex diseases and traits. In case-control GWAS, typical statistica... With recent advances in biotechnology, genome-wide association study (GWAS) has been widely used to identify genetic variants that underlie human complex diseases and traits. In case-control GWAS, typical statistical strategy is traditional logistical regression (LR) based on single-locus analysis. However, such a single-locus analysis leads to the well-known multiplicity problem, with a risk of inflating type I error and reducing power. Dimension reduction-based techniques, such as principal component-based logistic regression (PC-LR), partial least squares-based logistic regression (PLS-LR), have recently gained much attention in the analysis of high dimensional genomic data. However, the perfor- mance of these methods is still not clear, especially in GWAS. We conducted simulations and real data application to compare the type I error and power of PC-LR, PLS-LR and LR applicable to GWAS within a defined single nucleotide polymorphism (SNP) set region. We found that PC-LR and PLS can reasonably control type I error under null hypothesis. On contrast, LR, which is corrected by Bonferroni method, was more conserved in all simulation settings. In particular, we found that PC-LR and PLS-LR had comparable power and they both outperformed LR, especially when the causal SNP was in high linkage disequilibrium with genotyped ones and with a small effective size in simulation. Based on SNP set analysis, we applied all three methods to analyze non-small cell lung cancer GWAS data. 展开更多
关键词 principal components analysis partial least squares-based logistic regression genome-wide association study type I error POWER
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Logistics Regression Analysis between TCM Constitution Types of Patients with Hypertension,Insomnia and ABPM,PSQI 被引量:2
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作者 Xiaogang YU Qingsheng WANG +2 位作者 Erdan XIN Yujun LU Yingdong LI 《Medicinal Plant》 CAS 2022年第2期44-49,54,共7页
[Objectives]The research aimed to explore the distribution characteristics of TCM constitution types of patients with hypertension and insomnia,and study the clinical characteristics of patients with different constit... [Objectives]The research aimed to explore the distribution characteristics of TCM constitution types of patients with hypertension and insomnia,and study the clinical characteristics of patients with different constitutions,in order to provide new ideas for the treatment of patients with hypertension and insomnia.[Methods]Cross sectional observation method was used,and 420 patients with hypertension and insomnia were selected.Required information was collected,and the constitution type of traditional Chinese medicine was determined,and relevant data were recorded.SPSS and Logistic regression analysis method were used to explore the correlation between the distribution of TCM constitution types and gender,age,24 h-SBP,24 h-DBP,24 h-BPV,PSQI score,etc.[Results]Among 420 patients,the proportion of gentleness constitution was the most,and others in turn were Qi deficiency constitution>Yang deficiency constitution>phlegm dampness constitution>Qi stagnation constitution>Yin deficiency constitution>blood stasis constitution>damp heat constitution>special constitution.Among male patients,the proportion of gentleness constitution was the most.Among female patients,the proportion of Qi deficiency constitution was the most.In each constitution,the proportion of men and women was different,and the difference in gentleness constitution,Qi deficiency constitution and Yin deficiency constitution had statistical significance(P<0.05).The proportion of gentleness constitution for young and middle-aged patients was the most,while elderly patients with Qi deficiency constitution was the most.There was difference in the distribution of TCM constitution in different age groups,and the difference had statistical significance(P<0.05).Compared with the patients with gentleness constitution,the patients with Qi deficiency constitution,Yang deficiency constitution,Yin deficiency constitution,damp heat constitution,blood stasis constitution and Qi stagnation constitution had different differences in terms of age,24 h-SBP,24 h-DBP,24 h-BPV and PSQI score,and there was statistical significance(P<0.05).Except damp heat constitution,blood stasis constitution and special constitution,other constitutions had certain correlation with age,24 h-SBP,24 h-DBP,24 h-BPV and PSQI score.[Conclusions]TCM constitution types of patients with hypertension and insomnia were dominant by gentleness constitution,Qi deficiency constitution and Yang deficiency constitution.The distribution of TCM constitution in different gender and age groups was different,and different TCM constitution was related to ABPM and PSQI. 展开更多
关键词 Hypertension with insomnia Constitution of traditional Chinese medicine ABPM PSQI logistics regression analysis
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Landslide Susceptibility Assessment Using Conditional Analysis and Rare Events Logistics Regression: A Case-Study in the Antrodoco Area (Rieti, Italy) 被引量:1
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作者 Vittorio Chiessi Simona Toti Valerio Vitale 《Journal of Geoscience and Environment Protection》 2016年第12期1-21,共22页
This paper discusses some methodological aspects for the production of susceptibility maps of slope instability developed within the CARG Project (Geological Cartography of Italy at 1:50,000 scale). It describes an ex... This paper discusses some methodological aspects for the production of susceptibility maps of slope instability developed within the CARG Project (Geological Cartography of Italy at 1:50,000 scale). It describes an example of a susceptibility map in the presence of low susceptibility, using database having zero or negligible cost, with the aim to test some methodologies that can be easily reproducible to get a first estimate of the landslide susceptibility on a wide area. Two statistical approaches have been applied: the non-parametric conditional analysis and the logistic analysis for rare events. The predictive ability obtained from the two methodologies, was evaluated by the success-prediction curves for the conditional analysis, and by the Receiver Operating Characteristic curve (ROC), for the logistic model. The landslide susceptibility maps have been classified into four classes using both the Natural Breaks algorithm and the method proposed by Chung and Fabbri (2003). The paper considers the influence of these two classification methods on the quality of final results. 展开更多
关键词 Landslide Susceptibility Antrodoco Conditional analysis Rare Events logistic regression Classification Methods
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Usage as Complementary Correspondence Analysis and Logistic Regression in a Scientific Survey on Self Healing Methods
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作者 Zerrin Asan Greenacre Levent Terlemez Sevil Sentürk 《Open Journal of Statistics》 2014年第11期912-920,共9页
The aim of this study is to show complementary usage of logistic and correspondence analysis in a research subject to self-healing methodologies. Firstly, the number of the variables is reduced by logistic regression ... The aim of this study is to show complementary usage of logistic and correspondence analysis in a research subject to self-healing methodologies. Firstly, the number of the variables is reduced by logistic regression according to relationship between dependent and independent variables and then research carries on searching variables. The relationship among the behaviours of individuals and their demographic characteristics is modelled by logistic regression and shown graphically by correspondence analysis. In application, first of all, the effect of age, sex, marital status, education level, occupation and income level and present health condition, on appreciating self-health, is explained by a model. As a result of that model, it can be said that the effect of age, occupation and present health condition is reasonable. After analysing that model, the relationship between categorical variables (age, sex, occupation, preferred precautions, and worth of personal health) is shown graphically by multiple correspondence analysis. 展开更多
关键词 logistic regression CORRESPONDENCE analysis SELF HEALING
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Logistic Regression Analysis the Risk Factors of Peripherally Inserted Central Catheter Related Blood Stream Infection of Tumor Patients
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作者 Jian Song Yan Yan +2 位作者 Huang Yan Chunlin Wang Jun-e Hu 《Yangtze Medicine》 2017年第3期169-177,共9页
Objective: Our object is to study risk factors of tumor patients’ PICC catheter-related blood stream infection. Method: a retrospective analysis of data of 586 PICC catheterized patients was implemented, a univariate... Objective: Our object is to study risk factors of tumor patients’ PICC catheter-related blood stream infection. Method: a retrospective analysis of data of 586 PICC catheterized patients was implemented, a univariate analysis of general data and catheterizing data of tumor patients was then carried out, and data of single factors with statistical significance were incorporated into multi-factor Logistic regression model for analysis. Results: PICC catheter-related blood stream infection occurred to 16 patients, and occurrence rate was 2.73%. Multi-factor Logistic regression analysis results showed that number of puncturing times, positioning method and maintenance frequency were risk factors for tumor patients’ peripherally inserted central catheter catheter-related blood stream infection, and odds risk values were respectively 8.762, 9.253 and 10.324. Conclusion: for tumor patients implanted with peripherally inserted central catheters, using ECG positioning during strict sterile operation and catheterizing process to avoid repeated puncturing and increasing maintenance frequency could effectively reduce occurrence of PICC catheter-related blood stream infection. 展开更多
关键词 PICC RELATED BLOOD STREAM INFECTION logistic regression analysis Risk Factor
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Logistic Regression Analysis of Influencing Factors on Serum ALT and HCV RNA Changes in Patients with Chronic Hepatitis C
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作者 Cheng-bao Wang Jian-jie Chen +3 位作者 Hong-ming Nie Feng Gao Hua Lv Hong-ding Li 《国际感染病学(电子版)》 CAS 2012年第2期80-83,共4页
Objective This study was undertaken to investigate the influencing factors on serum ALT level and hepatitis C virus(HCV)RNA titer in chronic hepatitis C(CHC)patients.Methods All patients enrolled into this study were ... Objective This study was undertaken to investigate the influencing factors on serum ALT level and hepatitis C virus(HCV)RNA titer in chronic hepatitis C(CHC)patients.Methods All patients enrolled into this study were anti-HCV positive.Retrospective tracing method was applied to detect serum ALT level and HCV RNA titer and to collect general information of the patients such as genders,age groups,interferon medication history,infection pathways,height and weight.Then the multi-factor analysis was adopted with the application of binominal logistic regression mode.Results The abnormal rate of ALT level was positively correlated to HCV RNA and gender while negatively correlated to interferon medication history and age group,with Wald value of the 4 factors as 39.604,11.823,18.991 and 7.389,respectively.The positive rate of HCV RNA was negatively correlated to interferon medication history and gender while positively correlated to ALT level,with corresponding Wald value of the 3 factors as81.394,7.618 and 27.562,respectively.Conclusions The normal ALT level in HCV infected patients was associated with viral load,age,gender and interferon medication history,while the normal rate of HCV RNA titer was closely associated with gender,interferon medication history and ALT level. 展开更多
关键词 Multi-factor logistic regression analysis Hepatitis C virus Chronic Hepatitis C Serum ALT level HCV RNA
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A Comparative Study of Locality Preserving Projection and Principle Component Analysis on Classification Performance Using Logistic Regression
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作者 Azza Kamal Ahmed Abdelmajed 《Journal of Data Analysis and Information Processing》 2016年第2期55-63,共9页
There are a variety of classification techniques such as neural network, decision tree, support vector machine and logistic regression. The problem of dimensionality is pertinent to many learning algorithms, and it de... There are a variety of classification techniques such as neural network, decision tree, support vector machine and logistic regression. The problem of dimensionality is pertinent to many learning algorithms, and it denotes the drastic raise of computational complexity, however, we need to use dimensionality reduction methods. These methods include principal component analysis (PCA) and locality preserving projection (LPP). In many real-world classification problems, the local structure is more important than the global structure and dimensionality reduction techniques ignore the local structure and preserve the global structure. The objectives is to compare PCA and LPP in terms of accuracy, to develop appropriate representations of complex data by reducing the dimensions of the data and to explain the importance of using LPP with logistic regression. The results of this paper find that the proposed LPP approach provides a better representation and high accuracy than the PCA approach. 展开更多
关键词 logistic regression (LR) Principal Component analysis (PCA) Locality Preserving Projection (LPP)
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Logistic Regression在我国河流水系氮污染研究中的应用 被引量:11
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作者 高学民 陈静生 王立新 《环境科学学报》 CAS CSCD 北大核心 2000年第6期676-681,共6页
对四川省岷江、沱江及嘉陵江流域和江西省的赣江流域及鄱阳湖地区共 1 70多个水文站的数据进行了相关分析和多元回归分析 .结果表明 ,河流水中硝态氮浓度与年降雨量、人口密度、氮肥施用量、牲畜饲养量、农作物及粮食作物种植面积等因... 对四川省岷江、沱江及嘉陵江流域和江西省的赣江流域及鄱阳湖地区共 1 70多个水文站的数据进行了相关分析和多元回归分析 .结果表明 ,河流水中硝态氮浓度与年降雨量、人口密度、氮肥施用量、牲畜饲养量、农作物及粮食作物种植面积等因素有较好的相关性 .以以上数据资料为基础 ,将河流水NO3- N的浓度划分为背景浓度 (<0 7mg/L)、受人类活动的显著影响的NO3- N浓度 (>3 0mg/L)以及中间类 (0 7— 3 0mg/L)进行LogisticRegression分析 ,两个Logistic模型的准确度分别达 82 46%和 89 1 9% .运用Logistic模型对整个长江流域河流水中NO3- N浓度进行估计 ,结果与实测值基本相符合 . 展开更多
关键词 河流水 硝态氮 多元回归分析 污染源
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GIS-based logistic regression method for landslide susceptibility mapping in regional scale 被引量:9
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作者 ZHU Lei HUANG Jing-feng 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第12期2007-2017,共11页
Landslide susceptibility map is one of the study fields portraying the spatial distribution of future slope failure sus- ceptibility. This paper deals with past methods for producing landslide susceptibility map and d... Landslide susceptibility map is one of the study fields portraying the spatial distribution of future slope failure sus- ceptibility. This paper deals with past methods for producing landslide susceptibility map and divides these methods into 3 types. The logistic linear regression approach is further elaborated on by crosstabs method, which is used to analyze the relationship between the categorical or binary response variable and one or more continuous or categorical or binary explanatory variables derived from samples. It is an objective assignment of coefficients serving as weights of various factors under considerations while expert opinions make great difference in heuristic approaches. Different from deterministic approach, it is very applicable to regional scale. In this study, double logistic regression is applied in the study area. The entire study area is first analyzed. The logistic regression equation showed that elevation, proximity to road, river and residential area are main factors triggering land- slide occurrence in this area. The prediction accuracy of the first landslide susceptibility map was showed to be 80%. Along the road and residential area, almost all areas are in high landslide susceptibility zone. Some non-landslide areas are incorrectly divided into high and medium landslide susceptibility zone. In order to improve the status, a second logistic regression was done in high landslide susceptibility zone using landslide cells and non-landslide sample cells in this area. In the second logistic regression analysis, only engineering and geological conditions are important in these areas and are entered in the new logistic regression equation indicating that only areas with unstable engineering and geological conditions are prone to landslide during large scale engineering activity. Taking these two logistic regression results into account yields a new landslide susceptibility map. Double logistic regression analysis improved the non-landslide prediction accuracy. During calculation of parameters for logistic regres- sion, landslide density is used to transform nominal variable to numeric variable and this avoids the creation of an excessively high number of dummy variables. 展开更多
关键词 LANDSLIDE SUSCEPTIBILITY logistic regression GIS Spatial analysis
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A Review of the Logistic Regression Model with Emphasis on Medical Research 被引量:8
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作者 Ernest Yeboah Boateng Daniel A. Abaye 《Journal of Data Analysis and Information Processing》 2019年第4期190-207,共18页
This study explored and reviewed the logistic regression (LR) model, a multivariable method for modeling the relationship between multiple independent variables and a categorical dependent variable, with emphasis on m... This study explored and reviewed the logistic regression (LR) model, a multivariable method for modeling the relationship between multiple independent variables and a categorical dependent variable, with emphasis on medical research. Thirty seven research articles published between 2000 and 2018 which employed logistic regression as the main statistical tool as well as six text books on logistic regression were reviewed. Logistic regression concepts such as odds, odds ratio, logit transformation, logistic curve, assumption, selecting dependent and independent variables, model fitting, reporting and interpreting were presented. Upon perusing the literature, considerable deficiencies were found in both the use and reporting of LR. For many studies, the ratio of the number of outcome events to predictor variables (events per variable) was sufficiently small to call into question the accuracy of the regression model. Also, most studies did not report on validation analysis, regression diagnostics or goodness-of-fit measures;measures which authenticate the robustness of the LR model. Here, we demonstrate a good example of the application of the LR model using data obtained on a cohort of pregnant women and the factors that influence their decision to opt for caesarean delivery or vaginal birth. It is recommended that researchers should be more rigorous and pay greater attention to guidelines concerning the use and reporting of LR models. 展开更多
关键词 logistic regression Model Validation analysis GOODNESS-OF-FIT Measures Odds RATIO LIKELIHOOD RATIO TEST Hosmer-Lemeshow TEST Wald Statistic MEDICAL RESEARCH
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Regional Integrated Meteorological Forecasting and Warning Model for Geological Hazards Based on Logistic Regression 被引量:1
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作者 XU Jing YANG Chi ZHANG Guoping 《Wuhan University Journal of Natural Sciences》 CAS 2007年第4期638-644,共7页
Information model is adopted to integrate factors of various geosciences to estimate the susceptibility of geological hazards. Further combining the dynamic rainfall observations, Logistic regression is used for model... Information model is adopted to integrate factors of various geosciences to estimate the susceptibility of geological hazards. Further combining the dynamic rainfall observations, Logistic regression is used for modeling the probabilities of geological hazard occurrences, upon which hierarchical warnings for rainfall-induced geological hazards are produced. The forecasting and warning model takes numerical precipitation forecasts on grid points as its dynamic input, forecasts the probabilities of geological hazard occurrences on the same grid, and translates the results into likelihoods in the form of a 5-level hierarchy. Validation of the model with observational data for the year 2004 shows that 80% of the geological hazards of the year have been identified as "likely enough to release warning messages". The model can satisfy the requirements of an operational warning system, thus is an effective way to improve the meteorological warnings for geological hazards. 展开更多
关键词 geological hazard information model logistic regression RAINFALL spatial analysis
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The assessment of the outliers of logistic regression model and its clinical application 被引量:1
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作者 易东 许汝福 +1 位作者 张蔚 尹全焕 《Journal of Medical Colleges of PLA(China)》 CAS 1995年第1期61-62,66,共3页
On the basis of the newly developed regression diagnostic analysis, the diagnostic method with the assessment of the outliers of the logistic regression model was set up and it was used to analyze the prognosis of the... On the basis of the newly developed regression diagnostic analysis, the diagnostic method with the assessment of the outliers of the logistic regression model was set up and it was used to analyze the prognosis of the patients with acute lymphatic leukemia. 展开更多
关键词 OUTLIER logistic MODEL leukemia LYMPHOBLASTIC prognosis regression analysis
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Logistic Regression Analysis of Catheter Fixation Defects and Their Influencing Factors
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作者 Xiaoli LI 《Medicinal Plant》 2024年第6期63-65,共3页
[Objectives] To analyze the influencing factors of fixed defects in patients with catheter fixation in clinical nursing work, in order to provide the best catheter fixation nursing plan for patients.[Methods] 176 inpa... [Objectives] To analyze the influencing factors of fixed defects in patients with catheter fixation in clinical nursing work, in order to provide the best catheter fixation nursing plan for patients.[Methods] 176 inpatients with indwelling catheter from surgical system of Taihe Hospital in Shiyan City from August 2022 to March 2023 were selected. Using a retrospective analysis method, the influencing factors of catheter fixation defects in the study subjects were divided into two categories based on objective characteristics: type I non modifiable influencing factors and type II modifiable influencing factors. Using the standard for catheter fixation defects, whether the patient had catheter fixation defects was determined. After classified and statistically analyzed item by item, binary Logistic multiple regression analysis was used to identify the influencing factors.[Results] The occurrence of catheter fixation defects in patients with catheter fixation was related to factors such as whether the patient was evaluated before fixation, whether the fixation method was standardized and systematic, whether there was sufficient communication between nurses and patients, and the patient s knowledge of catheter fixation. It was also influenced by factors such as the patient s age, catheterization site, catheterization number, catheterization duration, where there was a consciousness disorder, educational level, and external environmental temperature.[Conclusions] Early attention to the key factors affecting patients with catheter fixation defects can effectively prevent adverse factors and provide patients with the best catheter fixation nursing plan to improve nursing quality. 展开更多
关键词 Catheter Fixed defect Influence factor logistic regression analysis
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Relative accuracy of spatial predictive models for lynx Lynx canadensis derived using logistic regression-AIC,multiple criteria evaluation and Bayesian approaches
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作者 Hejun KANG Shelley M. ALEXANDER 《Current Zoology》 SCIE CAS CSCD 北大核心 2009年第1期28-40,共13页
We compared probability surfaces derived using one set of environmental variables in three Geographic Information Systems (GIS) -based approaches: logistic regression and Akaike's Information Criterion (AIC), Mu... We compared probability surfaces derived using one set of environmental variables in three Geographic Information Systems (GIS) -based approaches: logistic regression and Akaike's Information Criterion (AIC), Multiple Criteria Evaluation (MCE), and Bayesian Analysis (specifically Dempster-Shafer theory). We used lynx Lynx canadensis as our focal species, and developed our environment relationship model using track data collected in Banff National Park, Alberta, Canada, during winters from 1997 to 2000. The accuracy of the three spatial models were compared using a contingency table method. We determined the percentage of cases in which both presence and absence points were correctly classified (overall accuracy), the failure to predict a species where it occurred (omission error) and the prediction of presence where there was absence (commission error). Our overall accuracy showed the logistic regression approach was the most accurate (74.51%). The multiple criteria evaluation was intermediate (39.22%), while the Dempster-Shafer (D-S) theory model was the poorest (29.90%). However, omission and commission error tell us a different story: logistic regression had the lowest commission error, while D-S theory produced the lowest omission error. Our results provide evidence that habitat modellers should evaluate all three error measures when ascribing confidence in their model. We suggest that for our study area at least, the logistic regression model is optimal. However, where sample size is small or the species is very rare, it may also be useful to explore and/or use a more ecologically cautious modelling approach (e.g. Dempster-Shafer) that would over-predict, protect more sites, and thereby minimize the risk of missing critical habitat in conservation plans . 展开更多
关键词 Bayesian analysis (Dempster-Shafer) GIS HABITAT logistic regression Lynx canadensis Multiple Criteria Evaluation (MCE)
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Logistic Regression for Prediction and Diagnosis of Bacterial Regrowth in Water Distribution System
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作者 董丽华 赵新华 +1 位作者 吴卿 杨幼安 《Transactions of Tianjin University》 EI CAS 2009年第5期371-374,共4页
This paper focuses on the quantitative expression of bacterial regrowth in water distribution system. Considering public health risks of bacterial regrowth,the experiment was performed on a distribution system of sele... This paper focuses on the quantitative expression of bacterial regrowth in water distribution system. Considering public health risks of bacterial regrowth,the experiment was performed on a distribution system of selected area.Physical,chemical,and microbiological parameters such as turbidity,temperature,residual chlorine and pH were measured over a three-month period and correlation analysis was carried out.Combined with principal components analysis(PCA) ,a logistic regression model is developed to predict and diagnose bacterial regrowth and locate the zones with high risks of microbiology in the distribution system.The model gives the probability of bacterial regrowth with the number of heterotrophic plate counts as the binary response variable and three new principal components variables as the explanatory variables.The veracity of the logistic regression model was 90%,which meets the precision requirement of the model. 展开更多
关键词 bacterial regrowth water distribution system heterotrophic plate counts logistic regression principal components analysis odds ratio veracity
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Survival Analysis of Logistics Service Providers: An Empirical Study of Chengdu, Area in China
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作者 Guoqi Li Yihuan Tu +4 位作者 Lihao Duan Jin Zhang Lei Huang Wanshan Wu Zhuoshi Lv 《Open Journal of Statistics》 2020年第6期915-935,共21页
This paper worked on a sample of 6791 logistics establishments registered in Chengdu, China over the period 1984-2016 to understand the survival status of </span><span style="font-family:Verdana;"&g... This paper worked on a sample of 6791 logistics establishments registered in Chengdu, China over the period 1984-2016 to understand the survival status of </span><span style="font-family:Verdana;">logistics service providers (LSPs) by non-parametric Kaplan-Meier estimation, together with Cox proportional hazard regression model, to identify factors affecting the failure of LSPs. In particular, it studies the interaction effect between LSPs’ size and entry timing and location. The empirical results show that: 1) Regarding the survival time, 1365 of the 6791 sample LSPs exited from the market by 2017. The exit rate is 20.1%, and the average life of the 6791 LSPs is about 6 years. 2) The survival of LSPs depends on their typology, ownership structure. And there is no significant difference in the probability of survival for both independent LSPs and logistics branches after controlling the effects of other variables. 3) Location and entry timing also play an important role in the survival of small-scale LSPs, but these factors cannot explain large-scale LSPs’ failure. 展开更多
关键词 logistics Service Providers Survival analysis Kaplan-Meier Estimation Cox Proportional Hazard regression
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Evaluation of the diagnostic value of tumor markers with ROC and logistic regression in gastrocolic tumors
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作者 Jinbo Liu Mingsu Zhou Yonglun Hang Meizhu Cai Min Song Ting Ye Kaizheng Wang 《The Chinese-German Journal of Clinical Oncology》 CAS 2011年第11期650-653,共4页
Objective: The aim of the study was to evaluate the clinical significance of multiple tumor markers (CEA, AFP, CA72-4 and CA19-9) in patients with gastrocolic tumors by receiver operating characteristic (ROC) curve an... Objective: The aim of the study was to evaluate the clinical significance of multiple tumor markers (CEA, AFP, CA72-4 and CA19-9) in patients with gastrocolic tumors by receiver operating characteristic (ROC) curve and stepwise logistic regression (LR) analysis. Methods: The serum concentrations of CEA, AFP, CA72-4 and CA19-9 were measured with electrochemiluminescence immunoassay in 126 patients with gastrocolic tumors, 137 patients with benign gastrocolic disorders and 109 healthy controls. The area under the ROC curve (AUC) of CEA, AFP, CA72-4 and CA19-9 and stepwise LR results were compared by sensitivity, specificity, Youden's index and positive likelihood ratio/negative likelihood ratio. Results: The levels of four tested tumor markers in patients with gastrocolic tumors were significantly higher than those in benign gastrocolic group and normal controls. In the benign gastrocolic group, the AUC from stepwise logistic regression was larger than the AUC of four tumor markers respectively. Sensitivity, Youden's index and positive likelihood ratio/negative likelihood ratio were the highest in the combination assay of CA72-4, CEA, and CA19-9, as compared with one of the tumor markers alone. Conclusion: The use of ROC established by LR analysis model improved the diagnostic accuracy of gastrocolic tumors. For the screening of gastrocolic tumors, the AUC value of the combination probability index (sensitivity and specificity) was significantly higher than the values of the different tumour markers. 展开更多
关键词 gastrocolic tumor tumor marker (TM) receiver operating characteristic (ROC) curve logistic regression (LR)analysis diagnosis
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Unveiling the Predictive Capabilities of Machine Learning in Air Quality Data Analysis: A Comparative Evaluation of Different Regression Models
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作者 Mosammat Mustari Khanaum Md Saidul Borhan +2 位作者 Farzana Ferdoush Mohammed Ali Nause Russel Mustafa Murshed 《Open Journal of Air Pollution》 2023年第4期142-159,共18页
Air quality is a critical concern for public health and environmental regulation. The Air Quality Index (AQI), a widely adopted index by the US Environmental Protection Agency (EPA), serves as a crucial metric for rep... Air quality is a critical concern for public health and environmental regulation. The Air Quality Index (AQI), a widely adopted index by the US Environmental Protection Agency (EPA), serves as a crucial metric for reporting site-specific air pollution levels. Accurately predicting air quality, as measured by the AQI, is essential for effective air pollution management. In this study, we aim to identify the most reliable regression model among linear discriminant analysis (LDA), quadratic discriminant analysis (QDA), logistic regression, and K-nearest neighbors (KNN). We conducted four different regression analyses using a machine learning approach to determine the model with the best performance. By employing the confusion matrix and error percentages, we selected the best-performing model, which yielded prediction error rates of 22%, 23%, 20%, and 27%, respectively, for LDA, QDA, logistic regression, and KNN models. The logistic regression model outperformed the other three statistical models in predicting AQI. Understanding these models' performance can help address an existing gap in air quality research and contribute to the integration of regression techniques in AQI studies, ultimately benefiting stakeholders like environmental regulators, healthcare professionals, urban planners, and researchers. 展开更多
关键词 regression analysis Air Quality Index Linear Discriminant analysis Quadratic Discriminant analysis logistic regression K-Nearest Neighbors Machine Learning Big Data analysis
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105例不孕症患者子宫输卵管造影结果影响因素的Logistic回归分析
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作者 李萍 匡继林 +2 位作者 王淑婷 李璐 徐佳 《湖南中医药大学学报》 CAS 2024年第7期1270-1276,共7页
目的探讨不孕症患者子宫输卵管造影结果发生异常的影响因素。方法选取2021年1月至2023年5月在湖南中医药大学第二附属医院妇科门诊就诊并接受X线子宫输卵管造影(X-ray hysterosalpingography,X-HSG)检查的105例不孕症患者,收集患者临床... 目的探讨不孕症患者子宫输卵管造影结果发生异常的影响因素。方法选取2021年1月至2023年5月在湖南中医药大学第二附属医院妇科门诊就诊并接受X线子宫输卵管造影(X-ray hysterosalpingography,X-HSG)检查的105例不孕症患者,收集患者临床资料包括年龄、月经周期、不孕症类型、支原体感染史、衣原体感染史、淋病奈瑟球菌感染史、盆腔炎相关病史、输卵管相关病史等,并填写《中医体质调查问卷表》,采用Logistic回归方程分析不孕症患者X-HSG结果的影响因素。结果X-HSG结果异常与盆腔炎相关病史、输卵管相关病史、年龄、气郁质及湿热质呈正相关(P<0.05),与不孕症类型、月经周期规律与否无相关性(P>0.05)。多因素Logistic回归分析结果显示:不孕症类型、月经周期、气郁质、湿热质是HSG发生异常的危险因素(OR>1),年龄、盆腔炎相关病史、输卵管相关病史是HSG发生异常的保护因素(OR<1)。结论适龄生育、减少盆腔炎相关病史、减少输卵管相关病史、调畅情志、忌食肥甘厚味对于减少输卵管病理损伤引起的不孕症至关重要。 展开更多
关键词 不孕症 子宫输卵管造影 logistic回归分析 影响因素
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