异常值检测算法在数据挖掘的诸多领域有着应用场景，例如金融领域，信息传输领域，图像领域等。在研究过程中，有学者给出了异常点的一个定义： An outlier is an observation that deviates so much from other observations as as to arouse suspicion that it was generated by a different mechanism.