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Fig8.1.9.2-2: Schematic CDF diagram showing negative EFI as the area between the M-climate curve and the ENS curve. The area is negative where the ENS curve (red line) is to the left (i.e. values less than) M-climate (black line). Note forecast values beyond the limits of the M-climate (green dashed line) are not used in evaluating EFI and so how extreme these actually are is not accounted for. The Shift of Tails (SOT) concept was developed in part to address this disadvantage.
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