Index Based Hidden Outlier Detection in Metric Space

Algorithm 4

Pivot selection.

Input: ,

Output:

(1) ;

(2) (); // is usually a data block of dataset

(3) blockIndex buildIndex();

(4) divide blockIndex into partNum equal segments; //

  and 10, every segment has the same number of points

(5) get pivotNum segments with smallest skip distance;

(6) pivot middle object of every smallest segment;

(7) return pivot;