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Depression recognition using functional connectivity based on dynamic causal model
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作者 罗国平 刘刚 +2 位作者 赵竟 姚志剑 卢青 《Journal of Southeast University(English Edition)》 EI CAS 2011年第4期367-369,共3页
Dynamic casual modeling of functional magnetic resonance imaging(fMRI) signals is employed to explore critical emotional neurocircuitry under sad stimuli. The intrinsic model of emotional loops is built on the basis... Dynamic casual modeling of functional magnetic resonance imaging(fMRI) signals is employed to explore critical emotional neurocircuitry under sad stimuli. The intrinsic model of emotional loops is built on the basis of Papez's circuit and related prior knowledge, and then three modulatory connection models are established. In these models, stimuli are placed at different points, which represents they affect the neural activities between brain regions, and these activities are modulated in different ways. Then, the optimal model is selected by Bayesian model comparison. From group analysis, patients' intrinsic and modulatory connections from the anterior cingulate cortex (ACC) to the right inferior frontal gyrus (rlFG) are significantly higher than those of the control group. Then the functional connection parameters of the model are selected as classifier features. The classification accuracy rate from the support vector machine(SVM) classifier is 80.73%, which, to some extent, validates the effectiveness of the regional connectivity parameters for depression recognition and provides a new approach for the clinical diagnosis of depression. 展开更多
关键词 depression recognition FMRI dynamic causal model Bayesian model selection
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Observed communication between oncologists and patients:A causal model of communication competence
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作者 Katie LaPlant Turkiewicz Mike Allen +1 位作者 Maria K Venetis Jeffrey D Robinson 《World Journal of Meta-Analysis》 2014年第4期186-193,共8页
AIM: To investigate and test a causal model derivedfrom previous meta-analytic data of health provider be-haviors and patient satisfaction.METHODS: A literature search was conducted forrelevant manuscripts that met ... AIM: To investigate and test a causal model derivedfrom previous meta-analytic data of health provider be-haviors and patient satisfaction.METHODS: A literature search was conducted forrelevant manuscripts that met the following criteria:Reported an analysis of provider-patient interaction inthe context of an oncology interview; the study hadto measure at least two of the variables of interest tothe model (provider activity, provider patient-centeredcommunication, provider facilitative communication,patient activity, patient involvement, and patient satis-faction or reduced anxiety); and the information had tobe reported in a manner that permitted the calculationof a zero-order correlation between at least two of thevariables under consideration. Data were transformedinto correlation coefficients and compiled to producethe correlation matrix used for data analysis. The test of the causal model is a comparison of the expected correlation matrix generated using an Ordinary Least Squares method of estimation. The expected matrix iscompared to the actual matrix of zero order correlation coeffcients. A model is considered a possible ft if the level of deviation is less than expected due to random sampling error as measured by a chi-square statistic. The signifcance of the path coeffcients was tested us-ing a z test. Lastly, the Sobel test provides a test of the level of mediation provided by a variable and provides an estimate of the level of mediation for each connec-tion. Such a test is warranted in models with multiple paths.RESULTS: A test of the original model indicated a lack of ft with the summary data. The largest discrepancy in the model was between the patient satisfaction and the provider patient-centered utterances. The observed correlation was far larger than expected given a medi-ated relationship. The test of a modifed model was un-dertaken to determine possible ft. The corrected model provides a fit to within tolerance as evaluated by the test statistic, χ2 (8, average n = 342) = 10.22. Each of the path coefficients for the model reveals that each one can be considered signifcant, P 〈 0.05. The Sobel test examining the impact of the mediating variables demonstrated that patient involvement is a signifcantmediator in the model, Sobel statistic = 3.56, P 〈 0.05. Patient active was also demonstrated to be a signifcant mediator in the model, Sobel statistic = 4.21, P 〈 0.05. The statistics indicate that patient behavior mediates the relationship between provider behavior and patient satisfaction with the interaction.CONCLUSION: The results demonstrate empirical support for the importance of patient-centered care and satisfy the need for empirical casual support of provider-patient behaviors on health outcomes. 展开更多
关键词 Provider-patient communication Communication competence ONCOLOGIST Cancer causal model META-ANALYSIS
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ICA Based Identification of Time-Varying Linear Causal Model
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作者 Hongxia Chen Jimin Ye 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2019年第4期32-40,共9页
Recently, several approaches have been proposed to discover the causality of the time-independent or fixed causal model. However, in many realistic applications, especially in economics and neuroscience, causality amo... Recently, several approaches have been proposed to discover the causality of the time-independent or fixed causal model. However, in many realistic applications, especially in economics and neuroscience, causality among variables might be time-varying. A time-varying linear causal model with non-Gaussian noise is considered and the estimation of the causal model from observational data is focused. Firstly, an independent component analysis(ICA) based two stage method is proposed to estimate the time-varying causal coefficients. It shows that, under appropriate assumptions, the time varying coefficients in the proposed model can be estimated by the proposed approach, and results of experiment on artificial data show the effectiveness of the proposed approach. And then, the granger causality test is used to ascertain the causal direction among the variables. Finally, the new approach is applied to the real stock data to identify the causality among three stock indices and the result is consistent with common sense. 展开更多
关键词 TIME-VARYING causal model independent component analysis(ICA) GRANGER causalITY test causalITY INFERENCE
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Application of causal model to maternal smoking cessation intervention in pregnancy
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作者 Rashid M. Ansari John B. Dixon +1 位作者 Colette Browning Saiqaa Y. Ansari 《Open Journal of Preventive Medicine》 2013年第4期347-354,共8页
The adverse effects of maternal smoking during pregnancy on both the offspring and women are well known. The main objective of this research article is to provide health professional causal modelling approach to make ... The adverse effects of maternal smoking during pregnancy on both the offspring and women are well known. The main objective of this research article is to provide health professional causal modelling approach to make a more comprehensive assessment of major determinants of smoking behaviour during and after pregnancy and consequently the outcomes of pregnant women smoking which are adversely affecting both the offspring and pregnant women. The causal model based on theory and evidence was modified and applied to material smoking cessation intervention to control the adverse effects of smoking on offspring obesity and neurodevelopment. In this approach a generic model links behavioural determinants, causally through behaviour, to physiological and biochemical variables, and health outcomes. It is tailored to context, target population, behaviours and health outcomes. The model provides a rational guide to appropriate measures, intervention points and intervention techniques, and can be tested quantitatively. The causal modelling approach showed promising results which can be used to help maternal smoking women to understand the risk of smoking and help them to quit smoking. The regression analysis of maternal smoking women BMI (n = 1000) on offspring BMI was statistically significant, p 0.05). This supported the hypothesis that maternal smoking women BMI during pregnancy is an important determinant of offspring obesity and consequently the risk factors of cardiovascular development. The causal modelling approach is unique as it provides an incentive to health professional to use these models to target any important and modifiable determinants of the maternal smoking behaviour and decrease the risk of adverse pregnancy outcomes for the offspring and the mother. 展开更多
关键词 Intervention PREGNANT Women MATERNAL SMOKING causal modelling OFFSPRING
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Two Causal-Modeling Approaches to Indicative Conditionals
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作者 ChingHui Su 《逻辑学研究》 2025年第6期43-61,共19页
Recently there have been two causal modelling approaches to indicative conditionals,i.e.extrapolationist(Deng&Lee,2021)and filterist(Liang&Wang,2022),although they all take an interventionist position on subju... Recently there have been two causal modelling approaches to indicative conditionals,i.e.extrapolationist(Deng&Lee,2021)and filterist(Liang&Wang,2022),although they all take an interventionist position on subjunctive conditionals.Motivated by the so-called OK pairs,they try to provide a convincing explanation of the intuition underlying the OK pairs.As far as we know,what they have done is to provide not only an explanation of the OK pairs,but also a way of distinguishing between indicative and subjunctive conditionals.Although we agree with their success in explaining the OK pairs within a causal modelling framework,we argue that their ways of distinguishing between indicative and subjunctive conditionals fail.Instead,we argue that their approaches can be used to distinguish between two readings of conditionals,the epistemic reading and the ontic reading.which can be applied to both indicative and subjunctive conditionals.We conclude by arguing that these two readings are related to two approaches to asking and answering causal questions:the“auses-of-effects"approach and the"effects-of-causes"approach. 展开更多
关键词 subjunctive conditionals extrapolationist causal modelling approaches epistemic reading causal modeling filterist indicative subjunctive con ok pairs
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A Modeling and Probabilistic Reasoning Method of Dynamic Uncertain Causality Graph for Industrial Fault Diagnosis 被引量:1
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作者 Chun-Ling Dong Qin Zhang Shi-Chao Geng 《International Journal of Automation and computing》 EI CSCD 2014年第3期288-298,共11页
Online automatic fault diagnosis in industrial systems is essential for guaranteeing safe, reliable and efficient operations.However, difficulties associated with computational overload, ubiquitous uncertainties and i... Online automatic fault diagnosis in industrial systems is essential for guaranteeing safe, reliable and efficient operations.However, difficulties associated with computational overload, ubiquitous uncertainties and insufficient fault samples hamper the engineering application of intelligent fault diagnosis technology. Geared towards the settlement of these problems, this paper introduces the method of dynamic uncertain causality graph, which is a new attempt to model complex behaviors of real-world systems under uncertainties. The visual representation to causality pathways and self-relied "chaining" inference mechanisms are analyzed. In particular, some solutions are investigated for the diagnostic reasoning algorithm to aim at reducing its computational complexity and improving the robustness to potential losses and imprecisions in observations. To evaluate the effectiveness and performance of this method, experiments are conducted using both synthetic calculation cases and generator faults of a nuclear power plant. The results manifest the high diagnostic accuracy and efficiency, suggesting its practical significance in large-scale industrial applications. 展开更多
关键词 Fault diagnosis causality model probabilistic graphical model uncertain knowledge representation weighted logic inference.
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Using granger-geweke causality model to evaluate the effective connectivity of primary motor cortex, supplementary motor area and cerebellum 被引量:1
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作者 Le Zhang Guangjin Zhong +3 位作者 Yukun Wu Mark G. Vangel Beini Jiang Jian Kong 《Journal of Biomedical Science and Engineering》 2010年第9期848-860,共13页
Currently, Granger-Geweke causality models have been widely applied to investigate the dynamic direction relationships among brain regions. In a previous study, we have found that the right hand finger-tapping task ca... Currently, Granger-Geweke causality models have been widely applied to investigate the dynamic direction relationships among brain regions. In a previous study, we have found that the right hand finger-tapping task can produce relatively reliable brain response. As an extension of our previous study, we developed an algorithm based on the classical Granger- Geweke causality model to further investigate the effective connectivity of three brain regions (left primary motor cortex (M1), supplementary motor area (SMA) and right cerebellum) that showed the most robust brain activations. Our computational results not only confirm the strong linear feedback among SMA, M1 and right cerebellum, but also demonstrate that M1 is the hub of these three regions indicated by the anatomy research. Moreover, the model predicts the high intermediate node density existing in the area between SMA and M1, which will stimulate the imaging experimentalists to carry out new experiments to validate this postulation. 展开更多
关键词 Granger-Geweke causalITY model Time Series Computational Neuroscience fMRI Finger-tapping Hand Movement MATH modeling
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基于因果图的研究前沿演化动因识别研究
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作者 白如江 任前前 +3 位作者 陈鑫 牛湘荷 张新雨 刘睿琳 《现代情报》 北大核心 2026年第2期45-60,共16页
[目的/意义]在全球科技创新格局加速重构背景下,揭示研究前沿演化的动因有助于为中国科技战略的前瞻布局提供情报支持。[方法/过程]基于BERTopic主题模型融合前沿判别指标,识别研究前沿主题,并运用主题相似度测度方法解析其演化路径。... [目的/意义]在全球科技创新格局加速重构背景下,揭示研究前沿演化的动因有助于为中国科技战略的前瞻布局提供情报支持。[方法/过程]基于BERTopic主题模型融合前沿判别指标,识别研究前沿主题,并运用主题相似度测度方法解析其演化路径。创新性地提出大语言模型与因果图融合分析方法,构建面向文本的因果要素智能抽取与结构化语义表征模型。结合Louvain算法构建领域因果图,借助关键节点测度、因果流模式建模和因果子图发现等方法,从关键驱动要素、作用模式及演化趋势3个层面揭示研究前沿演化的动因及其特征。[结果/结论]研究发现,生物交叉领域研究前沿演化的动因包含SARS-CoV-2、Alzheimer’s Disease、ALKBH3等事件要素,因果流模式和因果子图实现了因果环节与因果路径轨迹的刻画,为研究前沿主题演化深层次逻辑揭示提供了证据支持。 展开更多
关键词 研究前沿 主题演化 动因识别 大语言模型 因果图
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扩散模型引导的根因分析
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作者 王浩天 周学广 +4 位作者 王尚文 靳若春 黄万荣 杨文婧 王戟 《软件学报》 北大核心 2026年第2期621-640,共20页
根因分析是指找出引起复杂系统异常故障的根源因素.基于因果关系的溯因方法基于结构因果模型,是实现根因分析的最优选择之一.目前大多数因果驱动的根因分析方法大都需要数据因果结构的发现作为前置条件,这使得根因分析本身严重依赖于因... 根因分析是指找出引起复杂系统异常故障的根源因素.基于因果关系的溯因方法基于结构因果模型,是实现根因分析的最优选择之一.目前大多数因果驱动的根因分析方法大都需要数据因果结构的发现作为前置条件,这使得根因分析本身严重依赖于因果发现这一先验任务的效果.最近,基于得分函数的干预识别受到了广泛关注,其通过对比干预前后的得分函数导数的方差来检测被干预的变量集合,具备突破因果发现对根因分析约束的潜力.然而,主流的基于得分函数的干预识别大都受限于得分函数估计这一步骤,其采用的解析求解方法并不能很好地对真实的高维复杂数据分布进行建模.因此,鉴于最近在数据生成中取得的进展,提出一种扩散模型引导的根因分析策略.具体来说,所提方法首先利用扩散模型针对异常发生前后的数据分布对应的得分函数进行估计,进而通过观察对加权融合后的总体得分函数的一阶导方差,识别导致异常发生的根因变量集合.此外,为了进一步减小在识别过程中剪枝操作带来的扩散模型重复训练的开销,提出一种可靠的估计策略,其只需要训练一次扩散模型即可估计所有剪枝过程中对应节点的得分函数.在仿真数据和真实数据上的实验结果表明,所提出的方法实现了对于根因变量集合的精准识别.此外,相关的消融实验也表明,扩散模型的引导作用对于表现提升至关重要. 展开更多
关键词 根因分析 扩散模型 结构因果模型
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基于Modelica语言的电液伺服阀非因果建模仿真 被引量:8
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作者 李明 孟光 +1 位作者 荆建平 仲作阳 《系统仿真学报》 CAS CSCD 北大核心 2013年第12期2946-2951,共6页
针对电液伺服阀这一典型机械、电子、磁场、液压与控制耦合的复杂系统,考虑其多领域、多层次化的特点,应用多领域建模仿真语言Modelica对电液伺服阀进行建模仿真。不同于传统的电液伺服阀控制框图建模分析方法,Modelica语言的非因果性... 针对电液伺服阀这一典型机械、电子、磁场、液压与控制耦合的复杂系统,考虑其多领域、多层次化的特点,应用多领域建模仿真语言Modelica对电液伺服阀进行建模仿真。不同于传统的电液伺服阀控制框图建模分析方法,Modelica语言的非因果性与面向对象性,使得该方法具有强可读性,强可用性,便于修改等特点,克服了传统方法不能从底层元件反映伺服阀特性、考虑因果性、不易修改与重用的缺点。仿真结果显示,该方法可以反映电液伺服阀的动态特性,同时可以方便地通过参数修正对电液伺服阀进行优化设计,为电液伺服工程技术人员提供了电液伺服阀设计的更为高效便捷的手段。 展开更多
关键词 modelICA 非因果 电液伺服阀 建模 仿真 优化
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基于Modelica的MEMS系统级多领域建模与仿真 被引量:2
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作者 胡伟 魏昕 谢小柱 《传感技术学报》 CAS CSCD 北大核心 2009年第10期1413-1416,共4页
分析了现有的MEMS系统级建模与仿真方法,讨论了运用Modelica语言进行面向对象的非因果关系建模方法,建立了基于Modelica的电容式微型静电致动器系统级模型,仿真结果证明了Modelica用于MEMS系统级多领域仿真的可行性。
关键词 modelica多领域仿真 面向对象 非因果关系模型 微型静电致动器
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基于Modelica/Dymola的微谐振器建模与仿真 被引量:2
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作者 胡伟 魏昕 谢小柱 《计算机仿真》 CSCD 北大核心 2010年第10期79-82,共4页
针对MEMS的多领域耦合和系统级的快速建模与仿真要求,提出研究关于微型梳状静电谐振器建模与仿真方法。为提高系统的稳定性,减少误差,采用了基于Modelica/Dymola的非因果关系建模方法及流程,以梳状谐振器机电耦合模型的自然形式方程为基... 针对MEMS的多领域耦合和系统级的快速建模与仿真要求,提出研究关于微型梳状静电谐振器建模与仿真方法。为提高系统的稳定性,减少误差,采用了基于Modelica/Dymola的非因果关系建模方法及流程,以梳状谐振器机电耦合模型的自然形式方程为基础,以Modelica语言建立非因果关系的仿真模型,借助于Dymola平台对振子的位移/速度曲线进行仿真。仿真结果与理论验证相符,表明Modelica具有建模过程简单、建模速度快和仿真精度高等优点,适合于MEMS多领域建模与仿真研究。 展开更多
关键词 微型梳状静电谐振器 非因果关系模型 建模 仿真
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数据安全事件致因模型构建
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作者 王思思 丁蕾 刘涛影 《情报杂志》 北大核心 2026年第2期159-165,158,共8页
针对数据安全事件的复杂性与连锁性,构建数据安全事件致因模型,可为数据安全事件致因分析及防控提供依据和指导。首先,根据数据全生命周期循环(包括采集、传输、存储、共享、处理使用、销毁/更迭),提出数据安全事件防控全生命周期循环(... 针对数据安全事件的复杂性与连锁性,构建数据安全事件致因模型,可为数据安全事件致因分析及防控提供依据和指导。首先,根据数据全生命周期循环(包括采集、传输、存储、共享、处理使用、销毁/更迭),提出数据安全事件防控全生命周期循环(包括安全洞察、安全护航、安全堡垒、安全桥梁、安全工坊、安全归零/更新)。在此基础上,构建“数据全生命周期-数据安全事件防控全生命周期”双循环分析框架下的数据安全事件致因模型,识别数据安全事件风险传导的敏感节点,并结合不同规模的数据安全事件案例验证构建模型的逻辑完备性与实践有效性。研究表明,数据安全事件本质是“数据全生命周期-数据安全事件防控全生命周期”双循环系统的协同失灵,数据安全事件防控闭环的薄弱环节会穿透数据生命周期形成多米诺效应。数据全生命周期环节的失效会诱发数据安全事件防控全生命周期环节的防御性退化,验证了数据安全事件风险在“数据全生命周期-数据安全事件防控全生命周期”双循环体系中的放大效应。构建的数据安全事件致因模型通过解码数据安全事件风险跨循环传导机制,为构建自适应的数据安全事件防控体系提供了决策路径。 展开更多
关键词 数据安全 数据安全事件 事件致因 致因模型 事件防控
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Causal association rule mining methods based on fuzzy state description 被引量:1
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作者 Liang Kaijian Liang Quan Yang Bingru 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第1期193-199,共7页
Aiming at the research that using more new knowledge to develope knowledge system with dynamic accordance, and under the background of using Fuzzy language field and Fuzzy language values structure as description fram... Aiming at the research that using more new knowledge to develope knowledge system with dynamic accordance, and under the background of using Fuzzy language field and Fuzzy language values structure as description framework, the generalized cell Automation that can synthetically process fuzzy indeterminacy and random indeterminacy and generalized inductive logic causal model is brought forward. On this basis, a kind of the new method that can discover causal association rules is provded. According to the causal information of standard sample space and commonly sample space, through constructing its state (abnormality) relation matrix, causal association rules can be gained by using inductive reasoning mechanism. The estimate of this algorithm complexity is given,and its validiw is proved through case. 展开更多
关键词 knowledge discovery language field language value structure generalized cell automation generalized inductive logic causal model causal association rule.
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女性孕前血红蛋白水平与备孕结局的关联及异质性分析
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作者 王欣茹 李红乔 +5 位作者 张祎 丁小玲 巴磊 张学宁 王蓓 洪翔 《中华疾病控制杂志》 北大核心 2026年第3期285-293,共9页
目的探讨女性孕前血红蛋白水平与备孕结局的关联,为孕前健康管理和女性生育力保护提供依据。方法纳入2021―2023年于南京市鼓楼区妇幼保健所进行备孕检查的20~40岁备孕女性,构成研究队列,采集女性静脉血,检测孕前血红蛋白水平。随访1年... 目的探讨女性孕前血红蛋白水平与备孕结局的关联,为孕前健康管理和女性生育力保护提供依据。方法纳入2021―2023年于南京市鼓楼区妇幼保健所进行备孕检查的20~40岁备孕女性,构成研究队列,采集女性静脉血,检测孕前血红蛋白水平。随访1年内的备孕结局。探讨女性孕前血红蛋白与备孕结局的关联,并探索不同特征人群中该关联的异质性。结果最终纳入2491名符合要求的研究对象,其中满足世界卫生组织贫血诊断标准者188人(7.5%)。随访满1年,成功怀孕者805人。孕前血红蛋白水平与怀孕率的关联呈倒“U”型,调整所有协变量,总效应存在统计学意义(χ^(2)=31.54,P=0.035),而非线性检验无统计学关联(χ^(2)=1.73,P=0.188)。孕前贫血的平均因果效应为-0.039(95%CI:-0.041~-0.036),提示孕前贫血女性1年的怀孕率平均下降3.9%。结合特征重要性和相关分析,发现谷丙转氨酶(r=-0.35,P<0.001)、谷草转氨酶(r=-0.37,P<0.001)与个体因果效应呈负相关。在高谷丙转氨酶人群(>13 U/L)中进行贝叶斯logistic回归分析,在调整潜在混杂因素后发现,孕前贫血女性未来1年内怀孕率下降47%(median OR=0.53,参数的区间估计:0.28~0.96),且后验概率>97.0%。结论在高谷丙转氨酶备孕女性中,贫血可能会降低其怀孕率。对备孕女性开展健康体检,并有针对性地进行干预具有重要公共卫生学意义。 展开更多
关键词 女性生育力 孕前血红蛋白 备孕 异质性分析 因果森林模型
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一种基于因果关系的减轻大语言模型幻觉的方法
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作者 李鹤 迟昊昂 +1 位作者 刘明宇 杨文婧 《计算机工程与科学》 北大核心 2026年第2期245-255,共11页
大语言模型LLMs的出现是生成式人工智能的一个里程碑,其在文本理解和生成任务中取得了显著的成功。尽管LLMs在许多下游任务中取得了巨大的成功,但它们也存在严重的幻觉问题,对LLMs的实际应用是重大的挑战。虽然基于Transformer的LLMs中... 大语言模型LLMs的出现是生成式人工智能的一个里程碑,其在文本理解和生成任务中取得了显著的成功。尽管LLMs在许多下游任务中取得了巨大的成功,但它们也存在严重的幻觉问题,对LLMs的实际应用是重大的挑战。虽然基于Transformer的LLMs中的自注意力机制是一个重要的模块,但现有文献很少从自注意力机制的角度探讨LLMs的幻觉现象。为填补这一研究空白,从因果关系的角度研究了这个问题。具体而言,提出了一种方法,在不改变LLMs结构的情况下,禁用自注意力层。实验禁用多个开源LLMs中的不同自注意力层,在幻觉评估基准上对这些干预后的LLMs进行了评估,并将其幻觉程度与原始模型进行比较。实验结果表明,禁用LLMs前部或尾部的一些特定自注意力层可以缓解幻觉问题。 展开更多
关键词 大语言模型 大语言模型幻觉 因果表示学习
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基于图增强Transformer的事件因果关系识别
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作者 曾泽凡 成清 +1 位作者 刘忠 张亚豪 《中文信息学报》 北大核心 2026年第1期130-143,共14页
事件因果关系识别(ECI)旨在识别文本中事件之间的因果关系,为深入理解文本逻辑和语义提供线索。当前的事件因果关系识别方法受到事件表征困难和噪声数据等限制的影响,对隐式因果关系不敏感,文档级因果关系识别困难。针对上述问题,该文... 事件因果关系识别(ECI)旨在识别文本中事件之间的因果关系,为深入理解文本逻辑和语义提供线索。当前的事件因果关系识别方法受到事件表征困难和噪声数据等限制的影响,对隐式因果关系不敏感,文档级因果关系识别困难。针对上述问题,该文提出了一种联合模型—图增强Transformer。模型以Transformer为基础框架,利用大语言模型的丰富知识和强大语义理解能力生成先验因果图,以减少数据噪声并平衡标签。使用Longformer生成事件提及嵌入和自注意力权重,为因果图推理提供上下文表示和先验知识。然后,通过引入注意力掩码和自注意力初始化机制,将先验因果图和自注意力权重融入Transformer中。最后,设计了两种损失函数来训练和优化模型。实验表明,图增强Transformer的总体性能优于当前先进的方法,在文档级事件因果关系识别中综合性能F1值提升了1.4%,并且对文本长度有更强的鲁棒性。 展开更多
关键词 事件因果关系 先验因果图 TRANSFORMER 大语言模型 注意力机制
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基于深度强化学习的长期因果效应估计
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作者 柳家起 汪玉杰 +2 位作者 相国督 俞奎 曹付元 《计算机科学》 北大核心 2026年第4期235-244,共10页
因果效应估计旨在计算处理变量对结果变量的因果作用大小。现有主流因果效应估计方法主要适用于静态数据或时间序列中的单个时间点,无法有效估计处理变量在长期时间内对结果变量产生的累积影响。为解决这一问题,基于传统强化学习的长期... 因果效应估计旨在计算处理变量对结果变量的因果作用大小。现有主流因果效应估计方法主要适用于静态数据或时间序列中的单个时间点,无法有效估计处理变量在长期时间内对结果变量产生的累积影响。为解决这一问题,基于传统强化学习的长期因果效应估计方法通过线性基函数来拟合长期潜在结果,从而计算长期因果效应。然而,由于线性基函数在复杂场景下的表达能力有限,现有方法不能准确识别弱因果效应,同时在数据维度提高时会出现明显的性能退化问题。针对上述问题,提出了一种基于深度强化学习的长期因果效应估计方法。该方法采用对决网络估计长期潜在结果,能够有效估计处理变量对结果变量的影响,从而大幅提升算法对弱因果效应的识别能力;同时,所提方法避免了基函数选择不当而导致估计长期潜在结果时出现的偏差。实验结果表明,所提方法在统计学合成数据集和订单调度模拟数据集上优于现有算法。 展开更多
关键词 长期因果效应估计 潜在结果模型 深度强化学习
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基于IMB模型的年长矿工不安全行为致因机制
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作者 田方圆 李雯琪 +2 位作者 解学才 邱伟帅 李红霞 《中国安全科学学报》 北大核心 2026年第1期42-49,共8页
为应对由采矿业年长矿工人数占比增加带来的劳动力结构性安全风险,探究年长矿工不安全行为致因机制特征。基于信息-动机-行为技巧(IMB)模型构建矿工不安全行为致因机制结构方程模型(SEM),并运用多群组分析对比年长与年轻矿工不安全行为... 为应对由采矿业年长矿工人数占比增加带来的劳动力结构性安全风险,探究年长矿工不安全行为致因机制特征。基于信息-动机-行为技巧(IMB)模型构建矿工不安全行为致因机制结构方程模型(SEM),并运用多群组分析对比年长与年轻矿工不安全行为影响路径的系数差异。研究结果表明:学历、安全知识等知识经验因素,安全态度、事故经历、心理健康、工作倦怠、风险态度等心理特征因素均对矿工的不安全行为具有显著影响,其中,工作能力在“知识经验—不安全行为”与“心理特征—不安全行为”路径中均发挥中介作用。此外,风险态度、心理健康、工作倦怠、学历、安全知识对年长矿工不安全行为的影响均大于年轻矿工。 展开更多
关键词 信息-动机-行为技巧(IMB)模型 年长矿工 工作能力 不安全行为 致因机制 结构方程模型(SEM)
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结构因果模型中的规范性问题
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作者 刘牧 《自然辩证法研究》 北大核心 2026年第1期42-49,共8页
结构因果模型作为对实际因果颇有成效的刻画工具,所形成的关于因果的HP定义却遭遇了霍尔等哲学家的批评。其中围绕规范性、典型性及默认这一组概念开展的批评尤为关键,并形成了结构模型面临的多种反例。作为回应,哈尔彭在对HP定义的后... 结构因果模型作为对实际因果颇有成效的刻画工具,所形成的关于因果的HP定义却遭遇了霍尔等哲学家的批评。其中围绕规范性、典型性及默认这一组概念开展的批评尤为关键,并形成了结构模型面临的多种反例。作为回应,哈尔彭在对HP定义的后续修补中引入了“排序函数”,从而使得更新后的HP定义能够刻画原因事件的非典型性。然而以上修补方案仍然缺乏统一的衡量标准,且陷入了统计规范与社会规范等多种规范尺度间的冲突,因此仍然无法避免霍尔提出的相关批评。 展开更多
关键词 结构因果模型 规范性 因果 排序函数
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