文摘
Given a family of k + 1 real-valued functionsf0 , ?,fkf_0 , \ldots ,f_k defined on the set{ 1, ?,n}\{ 1, \ldots ,n\} and measuring the intensity of certain signals, we want to investigate whether these functions are T0 , ?,Tk ,T_0 , \ldots ,T_k , the size a of the collection of numbersj ? { 1, ?,n}j \in \{ 1, \ldots ,n\} whose signalsf0 (j), ?,fk (j)f_0 (j), \ldots ,f_k (j) exceed the corresponding threshold valuesT0 , ?,TkT_0 , \ldots ,T_k simultaneously for all0, ?,k0, \ldots ,k is surprisingly large (or small) in comparison to the family of cardinalities$
a_i : = \# \{ j \in \{ 1, \ldots ,n\} |f_i (j) > T_i \} \;(i = 0, \ldots ,k)
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a_i : = \# \{ j \in \{ 1, \ldots ,n\} |f_i (j) > T_i \} \;(i = 0, \ldots ,k)