A test for directional-linear independence, with applications to wildfire orientation and size

García-Portugués, EduardoBarros, Ana M.G.Crujeiras, Rosa M.González-Manteiga, WenceslaoPereira, J.M.C.2014-07-252014-07-252014"Stochastic Environmental Research and Risk Assessment". ISSN 1436-3240. 28 (5) (2014) 1261-1275http://hdl.handle.net/10400.5/6996Original PaperA nonparametric test for assessing the independence between a directional random variable (circular or spherical, as particular cases) and a linear one is proposed in this paper. The statistic is based on the squared distance between nonparametric kernel density estimates and its calibration is done by a permutation approach. The size and power characteristics of various variants of the test are investigated and compared with those for classical correlation-based tests of independence in an extensive simulation study. Finally, the best-performing variant of the new test is applied in the analysis of the relation between the orientation and size of Portuguese wildfiresengdirectional datadirectional-linear densityindependence testnonparametric estimationpermutationswildfiresA test for directional-linear independence, with applications to wildfire orientation and sizejournal article10.1007/s0477-013-0819-6