Data-based decision rules about the convexity of the support of a distribution

Given n independent, identically distributed random vectors in R-d, drawn from a common density f, one wishes to find out whether the support of f is convex or not. In this paper we describe a decision rule which decides correctly for sufficiently largen, with probability 1, whenever f is bounded aw...

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Detalles Bibliográficos
Autores: Delicado Useros, Pedro Francisco|||0000-0003-3933-4852, Hernández Huerta, Adolfo, Lugosi, Gábor
Tipo de recurso: artículo
Fecha de publicación:2014
País:España
Institución:Universitat Politècnica de Catalunya (UPC)
Repositorio:UPCommons. Portal del coneixement obert de la UPC
Idioma:inglés
OAI Identifier:oai:upcommons.upc.edu:2117/126661
Acceso en línea:https://hdl.handle.net/2117/126661
https://dx.doi.org/10.1214/14-EJS877
Access Level:acceso abierto
Palabra clave:Discernibility between hypotheses
bootstrap subsampling
U-statistics
set estimation
ISOMAP
dimensionality reduction
Density Level Sets
Rates
Classification
Framework
Classificació AMS::90 Operations research, mathematical programming
Àrees temàtiques de la UPC::Matemàtiques i estadística::Investigació operativa
Descripción
Sumario:Given n independent, identically distributed random vectors in R-d, drawn from a common density f, one wishes to find out whether the support of f is convex or not. In this paper we describe a decision rule which decides correctly for sufficiently largen, with probability 1, whenever f is bounded away from zero in its compact support. We also show that the assumption of boundedness is necessary. The rule is based on a statistic that is a second-orde U-statistic with a random kernel. Moreover, we suggest a way of approximating the distribution of the statistic under the hypothesis of convexity of the support. The performance of the proposed method is illustrated on simulated data sets. As an example of its potential statistical implications, the decision rule is used to automatically choose the tuning parameter of ISOMAP, a nonlinear dimensionality reduction method.