{"title":"Calibrated kNN classification via second-layer neighborhood analysis","authors":"Bastian Pfeifer, Markus Kreuzthaler","doi":"10.1007/s11634-025-00654-5","DOIUrl":"10.1007/s11634-025-00654-5","url":null,"abstract":"<div><p>The integration of artificial intelligence (AI) into medical practices has emphasized the importance of ensuring the reliability of predictive confidence, as it influences decision-making and the efficacy of AI-driven solutions. This paper focuses on the utilization of a non-parametric machine learning method, with a particular focus on the computation of confidence scores for individual classifications. Unlike parametric approaches, non-parametric techniques like k-nearest neighbors (kNN) offer flexibility without imposing strict data distribution assumptions. Leveraging this flexibility, we propose a novel kNN approach that introduces confidence-awareness through a two-layered neighborhood analysis. The developed approach is intended to support the classical non-parametric kNN classifier by providing more reliable and trustworthy class probabilities. Experimental evaluations conducted on benchmark datasets as well as a de-identified clinical real-world Electronic Health Records (EHR) data table consisting of thousands of unique class labels demonstrate the effectiveness of our approach in enhancing both, prediction accuracy and certainty assessment.</p></div>","PeriodicalId":49270,"journal":{"name":"Advances in Data Analysis and Classification","volume":"20 :","pages":"145 - 165"},"PeriodicalIF":1.3,"publicationDate":"2025-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s11634-025-00654-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147682807","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Arthur Tenenhaus, Michel Tenenhaus, Theo K. Dijkstra
{"title":"Structural equation modeling with factors and composites within the framework of the basic design","authors":"Arthur Tenenhaus, Michel Tenenhaus, Theo K. Dijkstra","doi":"10.1007/s11634-025-00647-4","DOIUrl":"10.1007/s11634-025-00647-4","url":null,"abstract":"<div><p>In this paper, we study structural equation modeling with factors and composites within the framework of the basic design. The PLS approach (i.e. PLS-SEM based on PLS-PM, PLSc and the composite model) used to estimate this model has many limitations, including lack of theoretical foundations and the use of iterative algorithms with no guaranteed convergence. To address these shortcomings, we introduce a novel method, SVD-SEM, which corrects these issues. Indeed, SVD-SEM relies on a non-iterative SVD-based algorithm for parameter estimation, producing consistent and asymptotically normal estimators, offering a statistically and computationally sound alternative to PLS-SEM. Additionally, we present the restricted maximum-likelihood approach (RML-SEM) for the basic design with factors and composites. SVD-SEM can serve as an initial solution for RML-SEM. To illustrate the performance of these methods, we discuss a Monte Carlo simulation on a nonrecursive model with factors and composites.</p></div>","PeriodicalId":49270,"journal":{"name":"Advances in Data Analysis and Classification","volume":"20 :","pages":"227 - 254"},"PeriodicalIF":1.3,"publicationDate":"2025-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s11634-025-00647-4.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147682810","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Editorial for ADAC issue 3 of volume 19 (2025)","authors":"Maurizio Vichi, Andrea Cerioli, Hans A. Kestler","doi":"10.1007/s11634-025-00652-7","DOIUrl":"10.1007/s11634-025-00652-7","url":null,"abstract":"","PeriodicalId":49270,"journal":{"name":"Advances in Data Analysis and Classification","volume":"19 3","pages":"545 - 549"},"PeriodicalIF":1.3,"publicationDate":"2025-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145078993","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Carlo Metta, Marco Fantozzi, Andrea Papini, Gianluca Amato, Matteo Bergamaschi, Andrea Fois, Silvia Giulia Galfrè, Alessandro Marchetti, Michelangelo Vegliò, Maurizio Parton, Francesco Morandin
{"title":"Increasing biases can be more efficient than increasing weights","authors":"Carlo Metta, Marco Fantozzi, Andrea Papini, Gianluca Amato, Matteo Bergamaschi, Andrea Fois, Silvia Giulia Galfrè, Alessandro Marchetti, Michelangelo Vegliò, Maurizio Parton, Francesco Morandin","doi":"10.1007/s11634-025-00649-2","DOIUrl":"10.1007/s11634-025-00649-2","url":null,"abstract":"<div><p>We introduce a novel computational unit for neural networks that features multiple biases, challenging the traditional perceptron structure. This unit emphasizes the importance of preserving uncorrupted information as it is passed from one unit to the next, applying activation functions later in the process with specialized biases for each unit. Through both empirical and theoretical analyses, we show that by focusing on increasing biases rather than weights, there is potential for significant enhancement in a neural network model’s performance. This approach offers an alternative perspective on optimizing information flow within neural networks. See source code (CurioSAI in Increasing biases can be more efficient than increasing weights, 2023. https://github.com/CuriosAI/dac-dev).\u0000</p></div>","PeriodicalId":49270,"journal":{"name":"Advances in Data Analysis and Classification","volume":"19 classification and related methods”","pages":"437 - 468"},"PeriodicalIF":1.3,"publicationDate":"2025-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145166365","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Paolo Giordani, Christian Hennig, Julien Jacques, Carla Rampichini
{"title":"Special issue on “Advances in clustering, classification and related methods”","authors":"Paolo Giordani, Christian Hennig, Julien Jacques, Carla Rampichini","doi":"10.1007/s11634-025-00645-6","DOIUrl":"10.1007/s11634-025-00645-6","url":null,"abstract":"","PeriodicalId":49270,"journal":{"name":"Advances in Data Analysis and Classification","volume":"19 classification and related methods”","pages":"271 - 273"},"PeriodicalIF":1.3,"publicationDate":"2025-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145170373","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Variational inference for estimating dynamic stochastic block models through an evolutionary algorithm","authors":"Luca Brusa, Fulvia Pennoni","doi":"10.1007/s11634-025-00634-9","DOIUrl":"10.1007/s11634-025-00634-9","url":null,"abstract":"<div><p>Dynamic temporal networks are important structures to capture node dependencies and their evolution over time. The dynamic stochastic block model, commonly used with longitudinal network data, is estimated maximizing the likelihood function through the variational expectation-maximization (VEM) algorithm. However, maximization is challenging due to the presence of multiple local maxima. In this paper, we first conduct a simulation study to assess the performance of six different parameter initialization strategies. Second, we introduce a novel specification of the VEM through a genetic algorithm, enabling a more comprehensive exploration of the parameter space. Results from both simulations and historical data on infectious disease transmission highlight the advantages of this approach in overcoming convergence to local maxima and improving node clustering in temporal network data.</p></div>","PeriodicalId":49270,"journal":{"name":"Advances in Data Analysis and Classification","volume":"19 classification and related methods”","pages":"469 - 492"},"PeriodicalIF":1.3,"publicationDate":"2025-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s11634-025-00634-9.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145168374","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Comparing flexible modelling approaches: the varying-thresholds model versus quantile regression","authors":"Niccolò Ducci, Leonardo Grilli, Marta Pittavino","doi":"10.1007/s11634-025-00635-8","DOIUrl":"10.1007/s11634-025-00635-8","url":null,"abstract":"<div><p>The varying-thresholds model (VTM) is a novel methodology proposed by Tutz ( Flexible predictive distributions from varying-thresholds modelling. https://doi.org/10.48550/arXiv.2103.13324, arXiv:2103.13324 2021) capable of estimating the whole conditional distribution of a response variable in a regression setting. It can be used for continuous, ordinal and count responses. In this study, conditional quantiles and prediction intervals estimated through VTM are compared with those of quantile regression. The comparison is based on a set of data-generating models to assess the performance of the two methodologies regarding the coverage and width of prediction intervals. The simulation study encompasses settings with several functional forms and types of errors. In addition, a discrete version of the continuous ranked probability score is proposed as a tool to choose the best link function for the binary models used in the fitting of VTM. In summary, the varying-thresholds model is a flexible methodology that can be broadly applied with light assumptions; it is advantageous over quantile regression when the conditional quantile function is misspecified.</p></div>","PeriodicalId":49270,"journal":{"name":"Advances in Data Analysis and Classification","volume":"19 classification and related methods”","pages":"493 - 514"},"PeriodicalIF":1.3,"publicationDate":"2025-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s11634-025-00635-8.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145165120","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Unsupervised learning from attributed networks","authors":"Lazhar Labiod, Mohamed Nadif","doi":"10.1007/s11634-025-00641-w","DOIUrl":"10.1007/s11634-025-00641-w","url":null,"abstract":"<div><p>Unlike the plain network where only the topological structure is available, nodes of attributed networks possess rich attributed information. Thereby, the attributed networks ubiquitous in the real world have attracted much attention in recent years. In our paper, to simultaneously address both attributed network embedding and clustering, we propose a new model. It exploits both content and structure/topological information, capitalizing on their simultaneous use. The proposed model relies on the approximation of the relaxed continuous embedding solution by the true discrete clustering. Thus, we show that incorporating an embedding representation provides simpler and more interpretable solutions. Moreover, we show how our proposed approach is related to some other clustering and data embedding methods. To clearly establish various connections, we propose to distinguish two variants. Experimental results demonstrate that the proposed algorithm performs better, in terms of clustering and embedding, than the state-of-the-art algorithms, including deep learning methods dedicated to similar tasks for attributed network datasets.</p></div>","PeriodicalId":49270,"journal":{"name":"Advances in Data Analysis and Classification","volume":"20 :","pages":"167 - 196"},"PeriodicalIF":1.3,"publicationDate":"2025-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147682843","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Geet Lahoti, Chitta Ranjan, Jialei Chen, Samaneh Ebrahimi, Chuck Zhang
{"title":"Censored trajectory data clustering using mixture of semi-Markov models with application to targeted marketing","authors":"Geet Lahoti, Chitta Ranjan, Jialei Chen, Samaneh Ebrahimi, Chuck Zhang","doi":"10.1007/s11634-025-00633-w","DOIUrl":"10.1007/s11634-025-00633-w","url":null,"abstract":"<div><p>A trajectory is a spatio-temporal data instance in which a customer or user moves between a set of discrete states while spending a certain amount of time in each state. Using trajectory data as a proxy for customers’ behavior and performing clustering can help to devise targeted marketing strategies. However, the censoring is often encountered due to the inability to observe the complete trajectories. In addition, the exact number of clusters is often unknown. In this work, we propose a novel mixture model-based clustering methodology to analyze the trajectory data and decipher different user segments based on their behavior. Each cluster is profiled using a semi-Markov model while considering the effect of censoring. Each entity is assigned to a cluster based on its similarity to the cluster’s profile. Entity assignments and cluster profiles are simultaneously inferred using a robust expectation maximization algorithm. In the simulation study, our methodology demonstrates better performance than existing methods. The effectiveness of our methodology is further corroborated using a real data set obtained from an internet music provider, where the obtained clustering results are found to be helpful in devising better marketing strategies to target users in different segments.</p></div>","PeriodicalId":49270,"journal":{"name":"Advances in Data Analysis and Classification","volume":"20 2","pages":"693 - 719"},"PeriodicalIF":2.1,"publicationDate":"2025-05-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s11634-025-00633-w.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148314721","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Correction to: Statistical jump model for mixed-type data with missing data imputation","authors":"Federico P. Cortese, Antonio Pievatolo","doi":"10.1007/s11634-025-00638-5","DOIUrl":"10.1007/s11634-025-00638-5","url":null,"abstract":"","PeriodicalId":49270,"journal":{"name":"Advances in Data Analysis and Classification","volume":"20 2","pages":"661 - 661"},"PeriodicalIF":2.1,"publicationDate":"2025-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s11634-025-00638-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148314720","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}