What is false alarm rate and false positive rate?

[Zhuowei Li <zhuowei () gmail com>]

Hi,

I am confused by the terms 'false positive rate' and 'false alarm
rate' within the context of intrusion detection. Does anybody about
what's the exact definition for these two terms?

Some literatures said 'false positive rate = false alarm rate', which
the number of false alarms divided by the number of alarms (true and
false).

Other said false positive rate is not equal to false alarm rate, the
false alarm rate is the same above definition, but the false positive
rate is "the total number of normal instances that were incorrectly
classified as intrusions divided by the total number of normal
instances"

Who is true, who is wrong within the context of intrusion detection?

Thanks.

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