To determine the best possible match between radar and insurance data, the thresholds used in the two radar criteria, ΔH and Zmax, were gradually changed. For all thresholds, quality measures in terms of POD, FAR, and HSS were quantified from the contingency table accumulated over the regions and years where insurance loss data are available
(2005–2011 for BI and 2005–2009 for VH data). In the year 2005, the month of April was not considered in the analysis due to largely unavailable radar data