In one approach to anomaly detection, objects are represented as points in a multidimensional space, and the points are grouped into successive shells, where each shell represents a layer around a grouping of points, such as a convex hull. An object is an anomaly if it lies in one of the outer shells.
(a) To which of the definitions of an anomaly in Section 10.1.2 is this defi-
nition most closely related?
(b) Name two problems with this definition of an anomaly.
(a) This definition is most closely related to the distance-based approach.
(b) i. For the convex hull approach, the distance of the points in a con-
vex hull from the center of the points can vary significantly if the
distribution of points in not symmetrical.
ii. This approach does not lend itself to assigning meaningful numer-
ical anomaly scores.
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A) entry parameters. B) structure analysis feature. C) data entry validation process. D) Input Mask property.
The concept of a class is useful because of its ____.
A. usability B. interchangeability C. functionality D. reusability