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Mostrando ítems 11-20 de 24
Artículo
Visualizing data as objects by DC (difference of convex) optimization
(Springer, 2017)
In this paper we address the problem of visualizing in a bounded region a set of individuals, which has attached a dissimilarity measure and a statistical value, as convex objects. This problem, which extends the standard ...
Artículo
The tree based linear regression model for hierarchical categorical variables
(Elsevier, 2022-05-04)
Many real-life applications consider nominal categorical predictor variables that have a hierarchical structure, e.g. economic activity data in Official Statistics. In this paper, we focus on linear regression models built ...
Artículo
Semi-obnoxious location models: a global optimization approach
(Elsevier, 1997-10-16)
In the last decades there has been an increasing interest in environmental topics. This interest has been reflected in modeling the location of obnoxious facilities, as shown by the important number of papers published ...
Artículo
A biobjective method for sample allocation in stratified sampling
(ELSEVIER SCIENCE BV, 2006-02-16)
The two main and contradicting criteria guiding sampling design are accuracy of estimators and sampling costs. In stratified random sampling, the sample size must be allocated to strata in order to optimize both objectives. ...
Artículo
On Mathematical Optimization for the visualization of frequencies and adjacencies as rectangular maps
(ELSEVIER SCIENCE BV, 2018-02-18)
In this paper, we address the problem of visualizing a frequency distribution and an adjacency relation attached to a set of individuals. We represent this information using a rectangular map, i.e., a subdivision of a ...
Artículo
A nested heuristic for parameter tuning in support vector machines
(Elsevier, 2014-03)
The default approach for tuning the parameters of a Support Vector Machine (SVM) is a grid search in the parameter space. Different metaheuristics have been recently proposed as a more efficient alternative, but they have ...
Artículo
Combining minsum and minmax: A goal programming approach
(INST OPERATIONS RESEARCH MANAGEMENT SCIENCES, 1999-07-01)
A number of methods for multiple-objective optimization problems (MOP) give as solution to MOP the set of optimal solutions for some single-objective optimization problems associated with it. Well-known examples of these ...
Artículo
Multi-group support vector machines with measurement costs a biobjective approach
(Elsevier, 2008-03)
Support Vector Machine has shown to have good performance in many practical classification settings. In this paper we propose, for multi-group classification, a biobjective optimization model in which we consider not only ...
Artículo
Strongly agree or strongly disagree? Rating features in support vector machines
(Elsevier, 2016-02)
In linear classifiers, such as the Support Vector Machine (SVM), a score is associated with each feature and objects are assigned to classes based on the linear combination of the scores and the values of the features. ...
Artículo
Sparsity in optimal randomized classification trees
(ELSEVIER SCIENCE BV, 2019-12-16)
Decision trees are popular Classification and Regression tools and, when small-sized, easy to interpret. Traditionally, a greedy approach has been used to build the trees, yielding a very fast training process; however, ...