摘要: Research in automated computer security intrusion detection, detection for short, is maturing. Several difficulties remain to be solved before systems become commonplace as part of real-world solutions. One such difficulty regards the subject effectiveness, how successful system at actually detecting intrusions with a high degree certainty. With this its starting point, paper discusses “base-rate fallacy” and it influences relative success an system, under set reasonable circumstances. The conclusion reached that false-alarm rate quickly becomes limiting factor.