Ordering Curves by Data Depth

Application of depth methods to functional data provides new tools of analysis, in particular an ordering of curves from the center outwards. Two specific depth definitions are band depth and half-region depth (Lopez-Pintado & Romo (2009). Journal of the American Statistical Association, 104, 718–734; Lopez-Pintado & Romo (2011). Computational Statistics & Data Analysis, 55, 1679–1695). Another research area is local depth (Agostinelli and Romanazzi (2011). Journal of Statistical Planning and Inference, 141, 817–830.) aimed to identify multiple centers and dense subsets of the space. In this work we suggest local versions for both band and half-region depth and illustrate an application with real data.