Receiver Operating Characteristics (ROC)
No dectability: 
Ideal detection: 
Area under ROC is a measure for detectability ! 
c3
 fn
 fs
c1
c2
c4
c5
Phit  
Pfa  
c5
c4
c2
c1
c3
c3
 fn
 fs
c1
c2
c4
c5
Phit 
Pfa  
c3
c2
c1
c4
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