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Heureka identified 5 AMEX cards in a single file and no other risk characteristics. The calculation is as follows.
Number of Characteristic Hits * Category Weight * Characteristic Weigh = File Risk Score
5 AMEX Hits * Credit Card Category Weight * AMEX Characteristic Weight = File Risk Score
5 * 0.8 * 0.9 = File Risk Score of 3.6
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