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High-dimensional large-scale mixed-type data imputation under missing at random

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Science China Mathematics 2025年

作者： Wei Liu Guizhen Li Ling Zhou Lan Luo School of Mathematics Sichuan University Center of Statistical Research and School of statistics Southwestern University of Finance and Economics department of statistics and Actuarial Science University of Iowa

Missingness in mixed-type variables is commonly encountered in a variety of areas. The requirement of complete observations necessities data imputation when a moderate or large proportion of data is ***, inappropriate imputation would downgrade the performance of machine learning algorithms, leading to bad predictions and unreliable statistical inference. For high-dimensional large-scale mixed-type missing data, we develop a computationally efficient imputation method, missing value imputation via generalized factor models（MIG）, under missing at random. The proposed MIG method allows missing variables to be of different types,including continuous, binary, and count variables, and are scalable to both data size n and variable dimension p while existing imputation methods rely on restrictive assumptions such as the same type of missing variables,the low dimensionality of variables, and a limited sample size. We explicitly show that the imputation error of the proposed MIG method diminishes to zero with the rate Op(max{n-1/2, p-1/2}) as both n and p tend to infinity. Five real datasets demonstrate the superior empirical performance of the proposed MIG method over existing methods that the average normalized absolute imputation error is reduced by 5.3%–34.1%.

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Enhancing insights into Global Cancer statistics 2022: implications for cancer control

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Science China Life Sciences 2025年第1期 294-296页

作者： Jingtong Xu Runtian Wang Xiaoxiang Guan department of Oncology the First Affiliated Hospital of Nanjing Medical University Jiangsu Key Lab of Cancer Biomarkers Prevention and TreatmentCollaborative Innovation Center for Personalized Cancer MedicineNanjing Medical University

Globally, there has been a marked escalation in tumor morbidity and mortality,cementing tumors as the predominant cause of death in numerous *** the current tumor burden across various regions is imperative to discern potential risk factors and formulate efficacious strategies for tumor ***, the International Agency for Research on Cancer(IARC) provided a status report on the global tumor burden,estimating the incidence and mortality of 36 cancers in 185 countries(Bray et al.,2024).

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Asymptotic false discovery control of the Benjamini-Hochberg procedure for pairwise comparisons

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Science China Mathematics 2025年第1期 223-252页

作者： Weidong Liu Dennis Leung Qi-Man Shao School of Mathematical Sciences Shanghai Jiao Tong University School of Mathematics and statistics University of Melbourne department of statistics and Data Science SICMSouthern University of Science and Technology

In a one-way analysis-of-variance(ANOVA) model,the number of pairwise comparisons can become large even with a moderate number of *** by this,we consider a regime with a growing number of groups and prove that,when testing pairwise comparisons,the Benjamini-Hochberg(BH) procedure can asymptotically control false discoveries,despite the fact that the involved t-statistics do not exhibit the wellknown positive dependence structure required for exact false discovery rate(FDR) *** Tukey's perspective that the difference between the means of any two groups cannot be exactly zero,our main result provides control over the directional false discovery rate and directional false discovery proportion.A key technical contribution of our work is demonstrating that the dependence among the t-statistics is sufficiently weak to establish the convergence result typically required for asymptotic FDR *** analysis does not rely on conventional assumptions such as normality,variance homogeneity,or a balanced design,thereby offering a theoretical foundation for applications in more general settings.

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统计学中微分几何的两例应用

中国科学:数学 2025年第1期 169-182页

作者：彭捷 department of statistics University of California Davis

本文讨论两个统计问题,其中微分几何的概念和观念发挥了关键作用.第一个问题涉及函数型数据的主成分估计,其中一部分参数具有正交约束,因此寻找最大似然估计需要在Stiefel流形上进行优化.第二个问题涉及对从扩散磁共振成像数据中估计出... 详细信息

本文讨论两个统计问题,其中微分几何的概念和观念发挥了关键作用.第一个问题涉及函数型数据的主成分估计,其中一部分参数具有正交约束,因此寻找最大似然估计需要在Stiefel流形上进行优化.第二个问题涉及对从扩散磁共振成像数据中估计出来的扩散张量进行核平滑.由于这些张量是3×3的正定矩阵,所以平滑过程需要在3×3的正定矩阵空间上定义,并且依赖于这个空间上特定度量的选择.

关键词： Stiefel流形典型度量 Newton法函数型数据主成分分析自然约化齐性空间扩散张量核平滑

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Practice patterns among ophthalmic surgeons in treating concomitant oculoplastic conditions in preoperative period:A questionnaire-based study

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World Journal of Clinical Cases 2025年第1期13卷 29-37页

作者： Bijnya Birajita Panda Chitaranjan Mishra Bhagabat Nayak Avik Kumar Roy Logesh Balakrishnan Priyadarshini Mishra department of Ophthalmology All India Institute of Medical SciencesBhubaneswar 751019OdishaIndia department of Vitreo-Retina Trilochan NetralayaSambalpur 768004India department of Glaucoma Services LV Prasad Eye InstituteBhubaneswar 751013India department of statistics Apollo HospitalsChennai 823104India

BACKGROUND Addressing oculoplastic conditions in the preoperative period ensures both the safety and functional success of any ophthalmic *** oculoplastic conditions,like nasolacrimal duct obstruction,have been extensively studied,whereas others,like eyelid malposition and thyroid eye disease,have received minimal or no *** To investigate the current practice patterns among ophthalmologists while treating concomitant oculoplastic conditions before any subspecialty ophthalmic *** A cross-sectional survey was disseminated among ophthalmologists all over *** survey included questions related to pre-operative evaluation,anaesthetic and surgical techniques preferred,post-operative care,the use of adjunctive therapies,and patient follow-up *** A total of 180 ophthalmologists responded to the *** practitioners(89%)felt that the ROPLAS test was sufficient during pre-operative evaluation before any subspecialty surgery was *** most common surgical techniques employed were lacrimal drainage procedures(Dacryocystorhinostomy)(63.3%),eyelid malposition repair(36.9%),and ptosis repair(58.7%).Post-operatively,47.7%of respondents emphasized that at least a 4-week gap should be maintained after lacrimal drainage procedures and eyelid ***-seven percent of ophthalmologists felt that topical anaesthetic procedures should be preferred while performing ocular surgeries in thyroid eye disease *** Approximately 50%of ophthalmologists handle prevalent oculoplastic issues themselves,seeking the expertise of an oculoplastic surgeon under particular *** ophthalmologists still favor using ROPLAS as a preliminary screening method before proceeding with cataract *** conditions and thyroid eye disease are not as commonly addressed before subspecialty procedures compared to issues like nasolacrimal duct obstruction and periocular infections.

关键词： Oculoplasty Ophthalmic plastic surgery Nasolacrimal duct obstruction Practice patterns Survey

Dynamic Multi-Graph Spatio-Temporal Graph Traffic Flow Prediction in Bangkok:An Application of a Continuous Convolutional Neural Network

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 579-607页

作者： Pongsakon Promsawat Weerapan Sae-dan Marisa Kaewsuwan Weerawat Sudsutad Aphirak Aphithana department of Civil Engineering Faculty of EngineeringRamkhamkaeng UniversityBangkok10240Thailand department of Computer Engineering Faculty of EngineeringRamkhamkaeng UniversityBangkok10240Thailand department of statistics Faculty of ScienceRamkhamkaeng UniversityBangkok10240Thailand

The ability to accurately predict urban traffic flows is crucial for optimising city ***,various methods for forecasting urban traffic have been developed,focusing on analysing historical data to understand complex mobility *** learning techniques,such as graph neural networks(GNNs),are popular for their ability to capture spatio-temporal ***,these models often become overly complex due to the large number of hyper-parameters *** this study,we introduce Dynamic Multi-Graph Spatial-Temporal Graph Neural Ordinary Differential Equation Networks(DMST-GNODE),a framework based on ordinary differential equations(ODEs)that autonomously discovers effective spatial-temporal graph neural network(STGNN)architectures for traffic prediction *** comparative analysis of DMST-GNODE and baseline models indicates that DMST-GNODE model demonstrates superior performance across multiple datasets,consistently achieving the lowest Root Mean Square Error(RMSE)and Mean Absolute Error(MAE)values,alongside the highest *** the BKK(Bangkok)dataset,it outperformed other models with an RMSE of 3.3165 and an accuracy of 0.9367 for a 20-min interval,maintaining this trend across 40 and 60 ***,on the PeMS08 dataset,DMST-GNODE achieved the best performance with an RMSE of 19.4863 and an accuracy of 0.9377 at 20 min,demonstrating its effectiveness over longer *** Los_Loop dataset results further emphasise this model’s advantage,with an RMSE of 3.3422 and an accuracy of 0.7643 at 20 min,consistently maintaining superiority across all time *** numerical highlights indicate that DMST-GNODE not only outperforms baseline models but also achieves higher accuracy and lower errors across different time intervals and datasets.

关键词： Graph neural networks convolutional neural network deep learning dynamic multi-graph spatio-temporal

Artificial Circulation System Algorithm:A Novel Bio-Inspired Algorithm

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 635-663页

作者： NerminÖzcan Semih Utku Tolga Berber department of Biomedical Technologies Dokuz Eylül UniversityIzmir35390Turkey department of Biomedical Engineering Iskenderun Technical UniversityIskenderun31200Turkey department of Computer Engineering Dokuz Eylül UniversityIzmir35390Turkey department of statistics and Computer Sciences Karadeniz Technical UniversityTrabzon61080Turkey

Metaheuristics are commonly used in various fields,including real-life problem-solving and engineering appli*** present work introduces a novel metaheuristic algorithm named the Artificial Circulatory System Algorithm(ACSA).The control of the circulatory system inspires it and mimics the behavior of hormonal and neural regulators involved in this *** work initially evaluates the effectiveness of the suggested approach on 16 two-dimensional test functions,identified as classical benchmark *** method was subsequently examined by application to 12 CEC 2022 benchmark problems of different ***,the paper evaluates ACSA in comparison to 64 metaheuristic methods that are derived from different approaches,including evolutionary,human,physics,and ***,a sequence of statistical tests was undertaken to examine the superiority of the suggested algorithm in comparison to the 7 most widely used algorithms in the existing *** results show that the ACSA strategy can quickly reach the global optimum,avoid getting trapped in local optima,and effectively maintain a balance between exploration and *** outperformed 42 algorithms statistically,according to post-hoc *** also outperformed 9 algorithms *** study concludes that ACSA offers competitive solutions in comparison to popüler methods.

关键词： Bio-inspired evolutionary heuristic metaheuristic optimization

Monochromatic energy computed tomography image for active intestinal hemorrhage:A model investigation

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World Journal of Gastroenterology 2015年第1期21卷 214-220页

作者： Wen-Dong Liu Xing-Wang Wu Jun-Mei Hu Bin Wang Bin Liu department of Radiology the First Affiliated Hospital of Anhui Medical University department of Epidemiology and statistics Anhui Medical University

AIM: To investigate the value of computed tomography(CT) spectral imaging in the evaluation of intestinal ***: Seven blood flow rates were simulated in *** spectral CT and mixed-energy CT scanswere performed for each rate(0.5,0.4,0.3,0.2,0.1,0.05 and 0.025 m L/min).The detection rates and the contrast-to-noise ratios(CNRs) of the contrast agent extravasation regions were compared between the two scanning methods in the arterial phase(AP) and the portal venous phase(PVP).Comparisons of the CNR values between the PVP and the AP were made for each energy level and carried out using a completely random t test.A χ2 test was used to compare the detection rates obtained from the two scanning ***: The total detection rates for energy spectral CT and mixed-energy CT in the AP were 88.57%(31/35) and 65.71%(23/35),respectively,and the difference was significant(χ2 = 5.185,P = 0.023); the total detection rates in the PVP were 100.00%(35/35) and 91.4%(32/35),respectively,and the difference was not significant(χ2 = 1.393,P = 0.238).In the AP,the CNR of the contrast agent extravasation regions was 3.58 ± 2.09 on the mixed-energy CT images,but the CNRs were 8.78 ± 7.21 and 8.83 ± 6.75 at 50 and 60 keV,respectively,on the single-energy CT images,which were significantly different(3.58 ± 2.09 vs 8.78 ± 7.21,P = 0.031; 3.58 ± 2.09 vs 8.83 ± 6.75,P = 0.029).In the PVP,the differences between the CNRs at 40,50 and 60 keV different monochromatic energy levels and the polychromatic energy images were significant(19.35 ± 10.89 vs 11.68 ± 6.38,P = 0.010; 20.82 ± 11.26 vs 11.68 ± 6.38,P = 0.001; 20.63 ± 10.07 vs 11.68 ± 6.38,P = 0.001).The CNRs at the different energy levels in the AP and the PVP were significantly different(t =-2.415,-2.380,-2.575,-2.762,-2.945,-3.157,-3.996 and-3.189).CONCLUSION: Monochromatic energy imaging spectral CT is superior to polychromatic energy images for the detection of intestinal hemorrhage,and the detection was easier in t

关键词： Spectral imaging Computed tomography Monochromatic

Association of cholesterol with risk of pancreatic cancer:A meta-analysis

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World Journal of Gastroenterology 2015年第12期21卷 3711-3719页

作者： Jia Wang Wei-Jing Wang Long Zhai Dong-Feng Zhang department of Epidemiology and Health statistics Qingdao University Medical College

AIM: To evaluate the effect of dietary cholesterol and serum total cholesterol(TC) on the risk of pancreatic cancer. METHODS: A literature search was performed up to June 2014 in Pub Med, EMBASE, China National Knowledge Infrastructure and China Biology medicalliterature database for relevant articles published in English or Chinese. Pooled relative risks(RRs) with 95% confidence intervals(CIs) were calculated with a random-effects model. RESULTS: We included 14 published articles with 439355 participants for dietary cholesterol, and 6 published articles with 1805697 participants for serum TC. For the highest vs lowest category of dietary cholesterol, the pooled RR(95%CI) of pancreatic cancer was 1.308(1.097-1.559). After excluding two studies(RR > 3.0), the pooled RR(95%CI) was 1.204(1.050-1.380). In subgroup analysis stratified by study design, the pooled RRs(95%CIs) were 1.523(1.226-1.893) for case-control studies and 1.023(0.871-1.200) for cohort studies. The association of dietary cholesterol with the risk of pancreatic cancer was significant for studies conducted in North America [1.275(1.058-1.537)] and others [2.495(1.565-3.977)], but not in Europe [1.149(0.863-1.531)]. No significant association [1.003(0.859-1.171)] was found between the risk of pancreatic cancer and serum TC. CONCLUSION: Dietary cholesterol may be associated with an increased risk of pancreatic cancer in worldwide populations, except for Europeans. The results need to be confirmed further.

关键词： Dietary cholesterol Serum total cholesterol Pancre