SORT : Statistics and Operations Research Transactions
SORT (ISSN 1696-2281 / ISSN electrònic 2013-8830) is an international biannual publication jointly published by Idescat and fours catalan universities (Universitat Politècnica de Catalunya, Universitat de Barcelona, Universitat Autònoma de Barcelona i Universitat de Girona) and with the collaboration of Regió Espanyola de la Societat Internacional de Biometria. Fully published in English (with abstracts in Catalan) promotes the publication of original articles on statistical methodology and applied statistics, operations research, official statistics and biometrics, as well as reviews of books and other publications in this field. SORT is published since 2003 and represents the third part of Qüestió (Quaderns d'Estadística i Investigació Operativa), published by Idescat since 1992.
Latest additions:
2017-01-10
08:36
18 p, 986.2 KB Modelling extreme values by the residual coefficient of variation / Castillo, Joan del (Universitat Autònoma de Barcelona. Secció de Matemàtiques) ; Padilla Cozar , Maria
The possibilities of the use of the coefficient of variation over a high threshold in tail modelling are discussed. The paper also considers multiple threshold tests for a generalized Pareto distribution, together with a threshold selection algorithm. [...]
2016
SORT : statistics and operations research transactions, Vol. 40 Núm. 2 (July-December 2016) , p. 303-320 (Articles)  
 Accés restringit a la UAB
2017-01-10
08:36
24 p, 409.1 KB Smoothed landmark estimators of the transition probabilities / Meira-Machado, Luís (University of Minho (Guimaraes, Portugal). Centre of Mathematics and Department of Mathematics and Applications)
One important goal in clinical applications of multi-state models is the estimation of transition probabilities. Recently, landmark estimators were proposed to estimate these quantities, and their superiority with respect to the competing estimators has been proved in situations in which the Markov condition is violated. [...]
2016
SORT : statistics and operations research transactions, Vol. 40 Núm. 2 (July-December 2016) , p. 375-398 (Articles)  
 Accés restringit a la UAB
2017-01-10
08:36
26 p, 2.4 MB Log-ratio methods in mixture models for compositional data sets / Comas-Cufí, Marc (Universitat de Girona. Departament d’Informàtica, Matemàtica Aplicada i Estadística) ; Martín-Fernández, Josep-Antoni (Universitat de Girona. Departament d’Informàtica, Matemàtica Aplicada i Estadística) ; Mateu-Figueras, Glòria (Universitat de Girona. Departament d’Informàtica, Matemàtica Aplicada i Estadística)
When traditional methods are applied to compositional data misleading and incoherent results could be obtained. Finite mixtures of multivariate distributions are becoming increasingly important nowadays. [...]
2016
SORT : statistics and operations research transactions, Vol. 40 Núm. 2 (July-December 2016) , p. 349-374 (Articles)  
 Accés restringit a la UAB
2017-01-10
08:36
28 p, 700.0 KB Using robust FPCA to identify outliers in functional time series, with applications to the electricity market / Vilar, Juan M. (Universidade da Coruña. Departamento de Matemáticas) ; Raña, Paula (Universidade da Coruña. Departamento de Matemáticas) ; Aneiros, Germán (Universidade da Coruña. Departamento de Matemáticas)
This study proposes two methods for detecting outliers in functional time series. Both methods take dependence in the data into account and are based on robust functional principal component analysis. [...]
2016
SORT : statistics and operations research transactions, Vol. 40 Núm. 2 (July-December 2016) , p. 321-348 (Articles)  
 Accés restringit a la UAB
2017-01-10
08:36
36 p, 1.9 MB A construction of continuous-time ARMA models by iterations of Ornstein-Uhlenbeck processes / Arratia, Argimiro (Universitat Politècnica de Catalunya. Departament de Llenguatges i Sistemes Informàtics) ; Cabaña, Alejandra (Universitat Autònoma de Barcelona. Departament de Matemàtiques) ; Cabaña, Enrique M. (Universidad de la República (Montevideo, Uruguai))
We present a construction of a family of continuous-time ARMA processes based on p iterations of the linear operator that maps a Lévy process onto an Ornstein-Uhlenbeck process. The construction resembles the procedure to build an AR(p) from an AR(1). [...]
2016
SORT : statistics and operations research transactions, Vol. 40 Núm. 2 (July-December 2016) , p. 267-302 (Articles)  
 Accés restringit a la UAB
2017-01-10
08:36
24 p, 168.7 KB Kernel-based estimation of P(X >Y) in ranked set sampling / Mahdizadeh, Mahdi (Hakim Sabzevari University (Sabzevar, Iran). Department of Statistics) ; Zamanzade, Ehsan (University of Isfahan (Iran). Department of Statistics)
This article is directed at the problem of reliability estimation using ranked set sampling. A nonparametric estimator based on kernel density estimation is developed. The estimator is shown to be superior to its analog in simple random sampling. [...]
2016
SORT : statistics and operations research transactions, Vol. 40 Núm. 2 (July-December 2016) , p. 243-266 (Articles)
2 documents
 Accés restringit a la UAB
2017-01-10
08:36
16 p, 140.8 KB Improving the resolution of the simple assembly line balancing problem type E / Corominas, Albert (Institute of Industrial and Control Engineering (Barcelona, Catalunya)) ; García-Villoria, Alberto (Institute of Industrial and Control Engineering (Barcelona, Catalunya)) ; Rafael Pastor, Rafael (Institute of Industrial and Control Engineering (Barcelona, Catalunya))
The simple assembly line balancing problem type E (abbreviated as SALBP-E) occurs when the number of workstations and the cycle time are variables and the objective is to maximise the line efficiency. [...]
2016
SORT : statistics and operations research transactions, Vol. 40 Núm. 2 (July-December 2016) , p. 227-242 (Articles)  
 Accés restringit a la UAB
2016-06-21
08:15
24 p, 294.5 KB A statistical learning based approach for parameter fine-tuning of metaheuristics / Calvet, Laura (Universitat Oberta de Catalunya) ; Juan, Angel A. (Universitat Oberta de Catalunya) ; Serrat, Carles (Universitat Politècnica de Catalunya. Departament de Matemàtica Aplicada I) ; Ries, Jana (University of Portsmouth. Portsmouth Business School)
Metaheuristics are approximation methods used to solve combinatorial optimization problems. Their performance usually depends on a set of parameters that need to be adjusted. The selectionof appropriate parameter values causes a loss of efficiency, as it requires time, and advanced analytical and problem-specific skills. [...]
2016
SORT : statistics and operations research transactions, Vol. 40 Núm. 1 (January-June 2016) , p. 201-224 (Articles)  
 Accés restringit a la UAB
2016-06-21
08:15
24 p, 260.6 KB Compound distributions motivated by linear failure rate / Gitifar, Narjes (Amirkabir University of Technology (Teheran, Iran)) ; Rezaei, Sadegh (Amirkabir University of Technology (Teheran, Iran)) ; Nadarajah, Saralees (University of Manchester)
Motivated by three failure data sets (lifetime of patients, failure time of hard drives and failure timeof a product), we introduce three different three-parameter distributions, study basic mathematical properties, address estimation by the method of maximum likelihood and investigate finite sample performance of the estimators. [...]
2016
SORT : statistics and operations research transactions, Vol. 40 Núm. 1 (January-June 2016) , p. 177-200 (Articles)  
 Accés restringit a la UAB
2016-06-21
08:15
24 p, 1.2 MB Transmuted geometric distribution with applications in modeling and regression analysis of count data / Chakraborty, Subrata (Dibrugarh University (Índia). Department of Statistics) ; Bhati, Deepesh (Central University of Rajasthan (Índia). Department of Statistics)
A two-parameter transmuted geometric distribution is proposed as a new generalization of the geometric distribution by employing the quadratic transmutation techniques of Shaw and Buckley. The additional parameter plays the role of controlling the tail length. [...]
2016
SORT : statistics and operations research transactions, Vol. 40 Núm. 1 (January-June 2016) , p. 153-176 (Articles)  
 Accés restringit a la UAB