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Analysis of risk factors leading to anxiety and depression in patients with prostate cancer after castration and the construction of a risk prediction model 被引量:1
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作者 Rui-Xiao Li Xue-Lian Li +4 位作者 Guo-Jun Wu Yong-Hua Lei Xiao-Shun Li Bo Li Jian-Xin Ni 《World Journal of Psychiatry》 SCIE 2024年第2期255-265,共11页
BACKGROUND Cancer patients often suffer from severe stress reactions psychologically,such as anxiety and depression.Prostate cancer(PC)is one of the common cancer types,with most patients diagnosed at advanced stages ... BACKGROUND Cancer patients often suffer from severe stress reactions psychologically,such as anxiety and depression.Prostate cancer(PC)is one of the common cancer types,with most patients diagnosed at advanced stages that cannot be treated by radical surgery and which are accompanied by complications such as bodily pain and bone metastasis.Therefore,attention should be given to the mental health status of PC patients as well as physical adverse events in the course of clinical treatment.AIM To analyze the risk factors leading to anxiety and depression in PC patients after castration and build a risk prediction model.METHODS A retrospective analysis was performed on the data of 120 PC cases treated in Xi'an People's Hospital between January 2019 and January 2022.The patient cohort was divided into a training group(n=84)and a validation group(n=36)at a ratio of 7:3.The patients’anxiety symptoms and depression levels were assessed 2 wk after surgery with the Self-Rating Anxiety Scale(SAS)and the Selfrating Depression Scale(SDS),respectively.Logistic regression was used to analyze the risk factors affecting negative mood,and a risk prediction model was constructed.RESULTS In the training group,35 patients and 37 patients had an SAS score and an SDS score greater than or equal to 50,respectively.Based on the scores,we further subclassified patients into two groups:a bad mood group(n=35)and an emotional stability group(n=49).Multivariate logistic regression analysis showed that marital status,castration scheme,and postoperative Visual Analogue Scale(VAS)score were independent risk factors affecting a patient's bad mood(P<0.05).In the training and validation groups,patients with adverse emotions exhibited significantly higher risk scores than emotionally stable patients(P<0.0001).The area under the curve(AUC)of the risk prediction model for predicting bad mood in the training group was 0.743,the specificity was 70.96%,and the sensitivity was 66.03%,while in the validation group,the AUC,specificity,and sensitivity were 0.755,66.67%,and 76.19%,respectively.The Hosmer-Lemeshow test showed aχ^(2) of 4.2856,a P value of 0.830,and a C-index of 0.773(0.692-0.854).The calibration curve revealed that the predicted curve was basically consistent with the actual curve,and the calibration curve showed that the prediction model had good discrimination and accuracy.Decision curve analysis showed that the model had a high net profit.CONCLUSION In PC patients,marital status,castration scheme,and postoperative pain(VAS)score are important factors affecting postoperative anxiety and depression.The logistic regression model can be used to successfully predict the risk of adverse psychological emotions. 展开更多
关键词 Prostate cancer CASTRATION Anxiety and depression risk factors risk prediction model
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Locally and globally uniform approximations for ruin probabilities of a nonstandard bidimensional risk model with subexponential claims
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作者 LIU Zai-ming GENG Bing-zhen WANG Shi-jie 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第1期98-113,共16页
Consider a nonstandard continuous-time bidimensional risk model with constant force of interest,in which the two classes of claims with subexponential distributions satisfy a general dependence structure and each pair... Consider a nonstandard continuous-time bidimensional risk model with constant force of interest,in which the two classes of claims with subexponential distributions satisfy a general dependence structure and each pair of the claim-inter-arrival times is arbitrarily dependent.Under some mild conditions,we achieve a locally uniform approximation of the finite-time ruin probability for all time horizon within a finite interval.If we further assume that each pair of the claim-inter-arrival times is negative quadrant dependent and the two classes of claims are consistently-varying-tailed,it shows that the above obtained approximation is also globally uniform for all time horizon within an infinite interval. 展开更多
关键词 bidimensional risk model asymptotic formula subexponential distribution consistently varying tail ruin probability
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Risk factors and risk prediction model for mucocutaneous separation in enterostomy patients:A single center experience
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作者 Yun Liu Hong Li +1 位作者 Jin-Jing Wu Jian-Hong Ye 《World Journal of Clinical Cases》 SCIE 2024年第33期6620-6628,共9页
BACKGROUND Mucocutaneous separation(MCS)is a common postoperative complication in enterostomy patients,potentially leading to significant morbidity.Early identification of risk factors is crucial for preventing this c... BACKGROUND Mucocutaneous separation(MCS)is a common postoperative complication in enterostomy patients,potentially leading to significant morbidity.Early identification of risk factors is crucial for preventing this condition.However,predictive models for MCS remain underdeveloped.AIM To construct a risk prediction model for MCS in enterostomy patients and assess its clinical predictive accuracy.METHODS A total of 492 patients who underwent enterostomy from January 2019 to March 2023 were included in the study.Patients were divided into two groups,the MCS group(n=110),and the non-MCS(n=382)based on the occurrence of MCS within the first 3 weeks after surgery.Univariate and multivariate analyses were used to identify the independent predictive factors of MCS and the model constructed.Receiver operating characteristic curve analysis was used to assess the model’s performance.RESULTS The postoperative MCS incidence rate was 22.4%.Suture dislodgement(P<0.0001),serum albumin level(P<0.0001),body mass index(BMI)(P=0.0006),hemoglobin level(P=0.0409),intestinal rapture(P=0.0043),incision infection(P<0.0001),neoadjuvant therapy(P=0.0432),stoma site(P=0.0028)and elevated intra-abdominal pressure(P=0.0395)were potential predictive factors of MCS.Suture dislodgement[P<0.0001,OR:28.007595%CI:(11.0901-82.1751)],serum albumin level(P=0.0008,OR:0.3504,95%CI:[0.1902-0.6485]),BMI[P=0.0045,OR:2.1361,95%CI:(1.2660-3.6235)],hemoglobin level[P=0.0269,OR:0.5164,95%CI:(0.2881-0.9324)],intestinal rapture[P=0.0351,OR:3.0694,95%CI:(1.0482-8.5558)],incision infection[P=0.0179,OR:0.2885,95%CI:(0.0950-0.7624)]and neoadjuvant therapy[P=0.0112,OR:1.9769,95%CI:(1.1718-3.3690)]were independent predictive factors and included in the model.The model had an area under the curve of 0.827 and good clinical utility on decision curve analysis.CONCLUSION The mucocutaneous separation prediction model constructed in this study has good predictive performance and can provide a reference for early warning of mucocutaneous separation in enterostomy patients. 展开更多
关键词 ENTEROSTOMY Mucocutaneous separation risk assessment model Performance validation
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Modeling,Simulation,and Risk Analysis of Battery Energy Storage Systems in New Energy Grid Integration Scenarios
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作者 Xiaohui Ye Fucheng Tan +4 位作者 Xinli Song Hanyang Dai Xia Li Shixia Mu Shaohang Hao 《Energy Engineering》 EI 2024年第12期3689-3710,共22页
Energy storage batteries can smooth the volatility of renewable energy sources.The operating conditions during power grid integration of renewable energy can affect the performance and failure risk of battery energy s... Energy storage batteries can smooth the volatility of renewable energy sources.The operating conditions during power grid integration of renewable energy can affect the performance and failure risk of battery energy storage system(BESS).However,the current modeling of grid-connected BESS is overly simplistic,typically only considering state of charge(SOC)and power constraints.Detailed lithium(Li)-ion battery cell models are computationally intensive and impractical for real-time applications and may not be suitable for power grid operating conditions.Additionally,there is a lack of real-time batteries risk assessment frameworks.To address these issues,in this study,we establish a thermal-electric-performance(TEP)coupling model based on a multitime scale BESS model,incorporating the electrical and thermal characteristics of Li-ion batteries along with their performance degradation to achieve detailed simulation of grid-connected BESS.Additionally,considering the operating characteristics of energy storage batteries and electrical and thermal abuse factors,we developed a battery pack operational riskmodel,which takes into account SOCand charge-discharge rate(Cr),using amodified failure rate to represent the BESS risk.By integrating detailed simulation of energy storage with predictive failure risk analysis,we obtained a detailed model for BESS risk analysis.This model offers a multi-time scale integrated simulation that spans month-level energy storage simulation times,day-level performance degradation,minutescale failure rate,and second-level BESS characteristics.It offers a critical tool for the study of BESS.Finally,the performance and risk of energy storage batteries under three scenarios—microgrid energy storage,wind power smoothing,and power grid failure response—are simulated,achieving a real-time state-dependent operational risk analysis of the BESS. 展开更多
关键词 Grid-connected battery energy storage system thermal-electric-performance coupling model operational risk model failure rate risk analysis
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Integrated Machine Learning and Deep Learning Models for Cardiovascular Disease Risk Prediction: A Comprehensive Comparative Study
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作者 Shadman Mahmood Khan Pathan Sakan Binte Imran 《Journal of Intelligent Learning Systems and Applications》 2024年第1期12-22,共11页
Cardiovascular Diseases (CVDs) pose a significant global health challenge, necessitating accurate risk prediction for effective preventive measures. This comprehensive comparative study explores the performance of tra... Cardiovascular Diseases (CVDs) pose a significant global health challenge, necessitating accurate risk prediction for effective preventive measures. This comprehensive comparative study explores the performance of traditional Machine Learning (ML) and Deep Learning (DL) models in predicting CVD risk, utilizing a meticulously curated dataset derived from health records. Rigorous preprocessing, including normalization and outlier removal, enhances model robustness. Diverse ML models (Logistic Regression, Random Forest, Support Vector Machine, K-Nearest Neighbor, Decision Tree, and Gradient Boosting) are compared with a Long Short-Term Memory (LSTM) neural network for DL. Evaluation metrics include accuracy, ROC AUC, computation time, and memory usage. Results identify the Gradient Boosting Classifier and LSTM as top performers, demonstrating high accuracy and ROC AUC scores. Comparative analyses highlight model strengths and limitations, contributing valuable insights for optimizing predictive strategies. This study advances predictive analytics for cardiovascular health, with implications for personalized medicine. The findings underscore the versatility of intelligent systems in addressing health challenges, emphasizing the broader applications of ML and DL in disease identification beyond cardiovascular health. 展开更多
关键词 Cardiovascular Disease Machine Learning Deep Learning Predictive modeling risk Assessment Comparative Analysis Gradient Boosting LSTM
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Uniform asymptotics for finite-time ruin probability in some dependent compound risk models with constant interest rate 被引量:1
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作者 杨洋 刘伟 +1 位作者 林金官 张玉林 《Journal of Southeast University(English Edition)》 EI CAS 2014年第1期118-121,共4页
Consider two dependent renewal risk models with constant interest rate. By using some methods in the risk theory, uniform asymptotics for finite-time ruin probability is derived in a non-compound risk model, where cla... Consider two dependent renewal risk models with constant interest rate. By using some methods in the risk theory, uniform asymptotics for finite-time ruin probability is derived in a non-compound risk model, where claim sizes are upper tail asymptotically independent random variables with dominatedly varying tails, claim inter-arrival times follow the widely lower orthant dependent structure, and the total amount of premiums is a nonnegative stochastic process. Based on the obtained result, using the method of analysis for the tail probability of random sums, a similar result in a more complex and reasonable compound risk model is also obtained, where individual claim sizes are specialized to be extended negatively dependent and accident inter-arrival times are still widely lower orthant dependent, and both the claim sizes and the claim number have dominatedly varying tails. 展开更多
关键词 compound and non-compound risk models finite-time ruin probability dominatedly varying tail uniformasymptotics random sums dependence structure
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The Logit Models to Analyze the Risk of Chinese High Technology Products Output
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作者 Lu Guo 《Chinese Business Review》 2003年第2期26-32,共7页
By developing 7 logit models, this study attempts to identify the independent variables, which influence the risk of the Chinese high technology products output. The total sample comprises 184 enterprises surveyed in ... By developing 7 logit models, this study attempts to identify the independent variables, which influence the risk of the Chinese high technology products output. The total sample comprises 184 enterprises surveyed in Gangdong province, Beijing and Shanghai from June to September of 2002.The most statistically significant independent variables are found to be the R&D proportion, the enterprise kind, the enterprise scale, the product kind and exporters. The study suggests that the logit model should be effectively used by enterprises and governments to assess the risk of high technology products output. 展开更多
关键词 Logit model risk Output
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ON THE EXPECTED DISCOUNTED PENALTY FUNCTION IN A MARKOV-DEPENDENT RISK MODEL WITH CONSTANT DIVIDEND BARRIER 被引量:7
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作者 刘娟 徐建成 胡亦钧 《Acta Mathematica Scientia》 SCIE CSCD 2010年第5期1481-1491,共11页
This article considers a Markov-dependent risk model with a constant dividend barrier. A system of integro-differential equations with boundary conditions satisfied by the expected discounted penalty function, with gi... This article considers a Markov-dependent risk model with a constant dividend barrier. A system of integro-differential equations with boundary conditions satisfied by the expected discounted penalty function, with given initial environment state, is derived and solved. Explicit formulas for the discounted penalty function are obtained when the initial surplus is zero or when all the claim amount distributions are from rational family. In two state model, numerical illustrations with exponential claim amounts are given. 展开更多
关键词 Markov-dependent risk model dividend barrier Cerber-Shiu function integro-differential equation Laplace transform
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Catastrophe theory-based risk evaluation model for water and mud inrush and its application in karst tunnels 被引量:19
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作者 ZHU Jian-qun LI Tian-zheng 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第5期1587-1598,共12页
This paper presents a risk evaluation model of water and mud inrush for tunnel excavation in karst areas.The factors affecting the probabilities of water and mud inrush in karst tunnels are investigated to define the ... This paper presents a risk evaluation model of water and mud inrush for tunnel excavation in karst areas.The factors affecting the probabilities of water and mud inrush in karst tunnels are investigated to define the dangerousness of this geological disaster.The losses that are caused by water and mud inrush are taken into consideration to account for its harmfulness.Then a risk evaluation model based on the dangerousness-harmfulness evaluation indicator system is constructed,which is more convincing in comparison with the traditional methods.The catastrophe theory is used to evaluate the risk level of water and mud inrush and it has great advantage in handling problems involving discontinuous catastrophe processes.To validate the proposed approach,the Qiyueshan tunnel of Yichang-Wanzhou Railway is taken as an example in which four target segments are evaluated using the risk evaluation model.Finally,the evaluation results are compared with the excavation data,which shows that the risk levels predicted by the proposed approach are in good agreements with that observed in engineering.In conclusion,the catastrophe theory-based risk evaluation model is an efficient and effective approach for water and mud inrush in karst tunnels. 展开更多
关键词 risk evaluation model water and mud inrush catastrophe theory karst area TUNNELING
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The Survival Probability in Generalized Poisson Risk Model 被引量:6
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作者 GONG Ri-zhao( Institute of Mathematics and Software, Xiangtan Polytechnic University, Xiangtan 411201, China) 《Chinese Quarterly Journal of Mathematics》 CSCD 2003年第2期134-139,共6页
In this paper we generalize the aggregated premium income process from a constant rate process to a poisson process for the classical compound Poinsson risk model,then for the generalized model and the classical compo... In this paper we generalize the aggregated premium income process from a constant rate process to a poisson process for the classical compound Poinsson risk model,then for the generalized model and the classical compound poisson risk model ,we respectively get its survival probability in finite time period in case of exponential claim amounts. 展开更多
关键词 risk model conditional expectation survival probability
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RUIN PROBABILITY IN A SEMI-MARKOV RISK MODEL WITH CONSTANT INTEREST FORCE AND HEAVY-TAILED CLAIMS 被引量:2
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作者 杨虎 薛凯 《Acta Mathematica Scientia》 SCIE CSCD 2013年第4期998-1006,共9页
In the present paper, we consider a kind of semi-Markov risk model (SMRM) with constant interest force and heavy-tailed claims~ in which the claim rates and sizes are conditionally independent, both fluctuating acco... In the present paper, we consider a kind of semi-Markov risk model (SMRM) with constant interest force and heavy-tailed claims~ in which the claim rates and sizes are conditionally independent, both fluctuating according to the state of the risk business. First, we derive a matrix integro-differential equation satisfied by the survival probabilities. Second, we analyze the asymptotic behaviors of ruin probabilities in a two-state SMRM with special claim amounts. It is shown that the asymptotic behaviors of ruin probabilities depend only on the state 2 with heavy-tailed claim amounts, not on the state 1 with exponential claim sizes. 展开更多
关键词 semi-Markov risk model constant interest force asymptotic behaviors heavy-tailed distributions
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DURATION OF NEGATIVE SURPLUS FOR A TWO STATE MARKOV-MODULATED RISK MODEL 被引量:2
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作者 马学敏 袁海丽 胡亦钧 《Acta Mathematica Scientia》 SCIE CSCD 2010年第4期1167-1173,共7页
We consider a continuous time risk model based on a two state Markov process, in which after an exponentially distributed time, the claim frequency changes to a different level and can change back again in the same wa... We consider a continuous time risk model based on a two state Markov process, in which after an exponentially distributed time, the claim frequency changes to a different level and can change back again in the same way. We derive the Laplace transform for the first passage time to surplus zero from a given negative surplus and for the duration of negative surplus. Closed-form expressions are given in the case of exponential individual claim. Finally, numerical results are provided to show how to estimate the moments of duration of negative surplus. 展开更多
关键词 Homogeneous Markov process ruin probability DEFICIT duration of negative surplus compound Poisson risk model
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Score model for predicting acute-on-chronic liver failure risk in chronic hepatitis B 被引量:5
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作者 Fang-Yuan Gao Yao Liu +10 位作者 Xiao-Shu Li Xie-Qiong Ye Le Sun Ming-Fan Geng Rui Wang Hui-Min Liu Xiao-Bing Zhou Li-Li Gu Yan-Min Liu Gang Wan Xian-Bo Wang 《World Journal of Gastroenterology》 SCIE CAS 2015年第27期8373-8381,共9页
AIM: To establish a clinical scoring model to predict risk of acute-on-chronic liver failure(ACLF) in chronic hepatitis B(CHB) patients.METHODS: This was a retrospective study of 1457 patients hospitalized for CHB bet... AIM: To establish a clinical scoring model to predict risk of acute-on-chronic liver failure(ACLF) in chronic hepatitis B(CHB) patients.METHODS: This was a retrospective study of 1457 patients hospitalized for CHB between October 2008 and October 2013 at the Beijing Ditan Hospital, Capital Medical University, China. The patients were divided into two groups: severe acute exacerbation(SAE) group(n = 382) and non-SAE group(n = 1075). The SAE group was classified as the high-risk group based on the higher incidence of ACLF in this group than in the non-SAE group(13.6% vs 0.4%). Two-thirds of SAE patients were randomly assigned to risk-model derivation and the other one-third to model validation. Univariate risk factors associated with the outcome were entered into a multivariate logistic regression model for screening independent risk factors. Each variable was assigned an integer value based on the regression coefficients, and the final score was the sum of these values in the derivation set. Model discrimination and calibration were assessed using area under the receiver operating characteristic curve and the Hosmer-Lemeshow test. RESULTS: The risk prediction scoring model includedthe following four factors: age ≥ 40 years, total bilirubin ≥ 171 μmol/L, prothrombin activity 40%-60%, and hepatitis B virus DNA > 107 copies/m L. The sum risk score ranged from 0 to 7; 0-3 identified patients with lower risk of ACLF, whereas 4-7 identified patients with higher risk. The Kaplan-Meier analysis showed the cumulative risk for ACLF and ACLF-related death in the two risk groups(0-3 and 4-7 scores) of the primary cohort over 56 d, and log-rank test revealed a significant difference(2.0% vs 33.8% and 0.8% vs 9.4%, respectively; both P < 0.0001). In the derivation and validation data sets, the model had good discrimination(C index = 0.857, 95% confidence interval: 0.800-0.913 and C index = 0.889, 95% confidence interval: 0.820-0.957, respectively) and calibration demonstrated by the Hosmer-Lemeshow test(χ2 = 4.516, P = 0.808 and χ2 = 1.959, P = 0.923, respectively).CONCLUSION: Using the scoring model, clinicians can easily identify patients(total score ≥ 4) at high risk of ACLF and ACLF-related death early during SAE. 展开更多
关键词 Acute-on-chronic LIVER failure Chronichepatitis B Prediction model risk SCORE SEVERE acuteexacerbation
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Risk assessment model of tunnel water inrush based on improved attribute mathematical theory 被引量:9
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作者 YANG Xiao-li ZHANG Sheng 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第2期379-391,共13页
Tunnel water inrush is one of the common geological disasters in the underground engineering construction.In order to effectively evaluate and control the occurrence of water inrush,the risk assessment model of tunnel... Tunnel water inrush is one of the common geological disasters in the underground engineering construction.In order to effectively evaluate and control the occurrence of water inrush,the risk assessment model of tunnel water inrush was proposed based on improved attribute mathematical theory.The trigonometric functions were adopted to optimize the attribute mathematical theory,avoiding the influence of mutation points and linear variation zones in traditional linear measurement functions on the accuracy of the model.Based on comprehensive analysis of various factors,five parameters were selected as the evaluation indicators for the model,including tunnel head pressure,permeability coefficient of surrounding rock,crushing degree of surrounding rock,relative angle of joint plane and tunnel section size,under the principle of dimension rationality,independence,directness and quantification.The indicator classifications were determined.The links among measured data were analyzed in detail,and the objective weight of each indicator was determined by using similar weight method.Thereby the tunnel water inrush risk assessment model is established and applied in four target segments of two different tunnels in engineering.The evaluation results and the actual excavation data agree well,which indicates that the model is of high credibility and feasibility. 展开更多
关键词 tunnel water inrush risk assessment model attribute mathematical theory nonlinear measurement function similar weight method
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Large Deviations for Random Sums on Some Kind of Heavy-tailed Classes in Risk Models 被引量:3
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作者 KONG Fan-chao WANG Jin-liang 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2006年第1期71-79,共9页
This paper is a further investigation into the large deviations for random sums of heavy-tailed,we extended and improved some results in ref. [1] and [2]. These results can applied to some questions in Insurance and F... This paper is a further investigation into the large deviations for random sums of heavy-tailed,we extended and improved some results in ref. [1] and [2]. These results can applied to some questions in Insurance and Finance. 展开更多
关键词 renewal risk model heavy-tailed distribution large deviation renewal counting process
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Development of a machine learning-based model for predicting risk of early postoperative recurrence of hepatocellular carcinoma 被引量:4
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作者 Yu-Bo Zhang Gang Yang +3 位作者 Yang Bu Peng Lei Wei Zhang Dan-Yang Zhang 《World Journal of Gastroenterology》 SCIE CAS 2023年第43期5804-5817,共14页
BACKGROUND Surgical resection is the primary treatment for hepatocellular carcinoma(HCC).However,studies indicate that nearly 70%of patients experience HCC recurrence within five years following hepatectomy.The earlie... BACKGROUND Surgical resection is the primary treatment for hepatocellular carcinoma(HCC).However,studies indicate that nearly 70%of patients experience HCC recurrence within five years following hepatectomy.The earlier the recurrence,the worse the prognosis.Current studies on postoperative recurrence primarily rely on postoperative pathology and patient clinical data,which are lagging.Hence,developing a new pre-operative prediction model for postoperative recurrence is crucial for guiding individualized treatment of HCC patients and enhancing their prognosis.AIM To identify key variables in pre-operative clinical and imaging data using machine learning algorithms to construct multiple risk prediction models for early postoperative recurrence of HCC.METHODS The demographic and clinical data of 371 HCC patients were collected for this retrospective study.These data were randomly divided into training and test sets at a ratio of 8:2.The training set was analyzed,and key feature variables with predictive value for early HCC recurrence were selected to construct six different machine learning prediction models.Each model was evaluated,and the bestperforming model was selected for interpreting the importance of each variable.Finally,an online calculator based on the model was generated for daily clinical practice.RESULTS Following machine learning analysis,eight key feature variables(age,intratumoral arteries,alpha-fetoprotein,preoperative blood glucose,number of tumors,glucose-to-lymphocyte ratio,liver cirrhosis,and pre-operative platelets)were selected to construct six different prediction models.The XGBoost model outperformed other models,with the area under the receiver operating characteristic curve in the training,validation,and test datasets being 0.993(95%confidence interval:0.982-1.000),0.734(0.601-0.867),and 0.706(0.585-0.827),respectively.Calibration curve and decision curve analysis indicated that the XGBoost model also had good predictive performance and clinical application value.CONCLUSION The XGBoost model exhibits superior performance and is a reliable tool for predicting early postoperative HCC recurrence.This model may guide surgical strategies and postoperative individualized medicine. 展开更多
关键词 Machine learning Hepatocellular carcinoma Early recurrence risk prediction models Imaging features Clinical features
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Risk prediction models for hepatocellular carcinoma in different populations 被引量:2
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作者 Xiao Ma Yang Yang +5 位作者 Hong Tu Jing Gao Yu-Ting Tan Jia-Li Zheng Freddie Bray Yong-Bing Xiang 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2016年第2期150-160,共11页
Hepatocellular carcinoma (HCC) is a malignant disease with limited therapeutic options due to its aggressive progression. It places heaW burden on most low and middle income countries to treat HCC patients. Nowadays... Hepatocellular carcinoma (HCC) is a malignant disease with limited therapeutic options due to its aggressive progression. It places heaW burden on most low and middle income countries to treat HCC patients. Nowadays accurate HCC risk predictions can help making decisions on the need for HCC surveillance and antiviral therapy. HCC risk prediction models based on major risk factors of HCC are useful and helpful in providing adequate surveillance strategies to individuals who have different risk levels. Several risk prediction models among cohorts of different populations for estimating HCC incidence have been presented recently by using simple, efficient, and ready-to-use parameters. Moreover, using predictive scoring systems to assess HCC development can provide suggestions to improve clinical and public health approaches, making them more cost-effective and effort-effective, for inducing personalized surveillance programs according to risk stratification. In this review, the features of risk prediction models of HCC across different populations were summarized, and the perspectives of HCC risk prediction models were discussed as well. 展开更多
关键词 risk prediction models hepatoceUular carcinoma chronic hepatitis B chronic hepatitis C CIRRHOSIS risk factors general population cohort study
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A Local Asymptotic Behavior for Ruin Probability in the Renewal Risk Model 被引量:1
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作者 MODIBO Diarra 《Wuhan University Journal of Natural Sciences》 CAS 2007年第3期407-411,共5页
Let R(t)=u+ct-∑ I=1^N(t) Xi,t≥0 be the renewal risk model, with Fx(x)being the distribution function of the claim amount X. Let ψ(u) be the ruin probability with initial surplus u. Under the condition of F... Let R(t)=u+ct-∑ I=1^N(t) Xi,t≥0 be the renewal risk model, with Fx(x)being the distribution function of the claim amount X. Let ψ(u) be the ruin probability with initial surplus u. Under the condition of Fx(x) ∈ S^*(γ),y ≥ 0, by the geometric sum method, we derive the local asymptotic behavior for ψ(u,u + z] for every 0 ( z ( oo, On one hand, the asymptotic behavior of ψ(u) can be derived from the result obtained. On the other hand, the result of this paper can be applied to the insurance risk management of an insurance company. 展开更多
关键词 renewal risk model subexponential class ruin probability
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Precise large deviations for sums of random vectors in a multidimensional size-dependent renewal risk model 被引量:1
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作者 SHEN Xin-mei FU Ke-ang ZHONG Xue-ting 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2018年第4期491-502,共12页
Consider a multidimensional renewal risk model, in which the claim sizes {Xk, k ≥1} form a sequence of independent and identically distributed random vectors with nonnegative components that are allowed to be depende... Consider a multidimensional renewal risk model, in which the claim sizes {Xk, k ≥1} form a sequence of independent and identically distributed random vectors with nonnegative components that are allowed to be dependent on each other. The univariate marginal distributions of these vectors have consistently varying tails and finite means. Suppose that the claim sizes and inter-arrival times correspondingly form a sequence of independent and identically distributed random pairs, with each pair obeying a dependence structure. A precise large deviation for the multidimensional renewal risk model is obtained. 展开更多
关键词 Precise large deviation SIZE-DEPENDENT Consistent variation Multidimensional risk model Renewal counting process
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Survival probability and ruin probability of a risk model 被引量:1
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作者 LUO Jian-hua College of Science,Central South University of Forestry and Technology,Changsha 410004,China Institute of Statistics,Central South University of Forestry and Technology,Changsha 410004,China. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2008年第3期256-264,共9页
In this paper, a new risk model is studied in which the rate of premium income is regarded as a random variable, the arrival of insurance policies is a Poisson process and the process of claim occurring is p-thinning ... In this paper, a new risk model is studied in which the rate of premium income is regarded as a random variable, the arrival of insurance policies is a Poisson process and the process of claim occurring is p-thinning process. The integral representations of the survival probability are gotten. The explicit formula of the survival probability on the infinite interval is obtained in the special casc cxponential distribution.The Lundberg inequality and the common formula of the ruin probability are gotten in terms of some techniques from martingale theory. 展开更多
关键词 risk model thinning process survival probability MARTINGALE ruin probability integral representation
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