Extremal Dependence Indices: Improved Verification Measures for Deterministic Forecasts of Rare Binary Events

• DOI: 10.1175/waf-d-10-05030.1
• Publication Date: 2011-04-07T20:55:31Z
• Authors: Christopher A. T....; David B. Stephenson
• Keywords: Complement; Base (topology)

Abstract Verifying forecasts of rare events is challenging, in part because traditional performance measures degenerate to trivial values as become rarer. The extreme dependency score was proposed recently a nondegenerating measure for the quality deterministic binary events. This has some undesirable properties, including being both easy hedge and dependent on base rate. A symmetric also recently, but this too These two scores their properties are reviewed meanings several such base-rate dependence complement symmetry that have caused confusion clarified. Two modified versions score, extremal index, then shown overcome all its shortcomings. new nondegenerating, independent, asymptotically equitable, harder hedge, regular isopleths correspond asymmetric relative operating characteristic curves.