“…Via (3.1), it is possible to transform between (a r , b r ) and (ã r , br ) if the extremal index θ is known or estimated. Regarding the estimation of the extremal index, a large variety of estimators has been proposed, which may itself be grouped into four categories: 1) BM-like estimators based on "blocking" techniques (Northrop, 2015;Berghaus and Bücher, 2017), 2) POT-like estimators that rely on threshold exceedances (Ferro and Segers, 2003;Süveges, 2007), 3) estimators that use both principles simultaneously (Hsing, 1993;Robert, 2009;Robert, Segers and Ferro, 2009) and 4) estimators which, next to choosing a threshold sequence, require the choice of a run-length parameter (Smith and Weissman, 1994;Weissman and Novak, 1998). Since the distance between the time points at which the maxima within two successive blocks are attained is likely to be quite large, the sample X BM can be regarded as approximately independent.…”