Application-Level Unsupervised Outlier-Based Intrusion Detection and Prevention

Table 3

R-precision (%) for different distance function (DF) and k-nearest neighbors (LOF.k) values.

LOF.k	50	60	70	80	90	100	150	250	400	700	850	1000	1250	1500
DF
Clark	14.10	14.10	58.97	75.64	76.92	82.05	89.74	96.15	97.44	97.44	94.87	93.59	92.31	92.31
Euclidean	70.51	78.21	87.18	85.90	76.92	76.92	67.95	55.13	44.87	35.90	92.31	92.31	92.31	92.31
Manhattan	69.23	69.23	74.36	74.36	65.38	60.26	55.13	46.15	38.46	26.92	92.31	92.31	92.31	92.31
Pearson	34.62	61.54	88.46	88.46	88.46	87.18	84.62	83.33	75.64	61.54	91.03	91.03	91.03	84.62