Table 6: Cost per example (mean ± std) per detector aggregated over the datasets. The table is divided into three parts, where each part has different costs (false positives, false negatives, rejection). Results show that REJEX obtains a lower average cost in all cases but one (KDE).
DET.	COST PER EXAMPLE FOR THREE COST FUNCTIONS (MEAN ± STD)
REJEX	SS-REPEN	MV	ENS	UDR	EM	STABILITY	NOREJECT
FALSE POSITIVE COST = 10, FALSE NEGATIVE COST = 1, REJECTION COST = min{10(1-γ),γ}
AE	0.504 ± 0.626	0.584 ± 0.723	0.697 ± 0.763	0.661 ± 0.830	0.703 ± 0.829	0.766 ± 0.841	0.768 ± 0.826	0.825 ± 0.873
COPOD	0.491 ± 0.637	0.593 ± 0.706	0.686 ± 0.746	0.618 ± 0.726	0.707 ± 0.788	0.778 ± 0.825	0.785 ± 0.801	0.781 ± 0.833
ECOD	0.479 ± 0.628	0.584 ± 0.727	0.625 ± 0.705	0.642 ± 0.755	0.711 ± 0.774	0.748 ± 0.803	0.770 ± 0.783	0.771 ± 0.817
GMM	0.568 ± 0.713	0.589 ± 0.752	0.823 ± 0.878	0.715 ± 0.929	0.790 ± 0.925	0.941 ± 0.948	0.889 ± 0.929	0.950 ± 0.967
HBOS	0.475 ± 0.595	0.569 ± 0.758	0.666 ± 0.693	0.697 ± 0.732	0.709 ± 0.764	0.776 ± 0.803	0.771 ± 0.770	0.809 ± 0.816
IFOR	0.477 ± 0.602	0.575 ± 0.712	0.665 ± 0.718	0.634 ± 0.731	0.683 ± 0.786	0.776 ± 0.818	0.763 ± 0.788	0.808 ± 0.831
INNE	0.479 ± 0.592	0.567 ± 0.698	0.752 ± 0.724	0.820 ± 0.795	0.815 ± 0.787	0.819 ± 0.793	0.818 ± 0.792	0.823 ± 0.799
KDE	0.602 ± 0.827	0.589 ± 0.704	0.819 ± 0.947	0.740 ± 0.913	0.793 ± 0.939	0.897 ± 0.945	0.774 ± 0.906	0.914 ± 0.945
KNN	0.498 ± 0.577	0.596 ± 0.726	0.741 ± 0.734	0.669 ± 0.720	0.669 ± 0.736	0.777 ± 0.747	0.739 ± 0.735	0.800 ± 0.749
LODA	0.518 ± 0.619	0.574 ± 0.709	0.574 ± 0.647	0.689 ± 0.729	0.701 ± 0.748	0.697 ± 0.682	0.827 ± 0.797
LOF	0.539 ± 0.623	0.603 ± 0.742	0.898 ± 0.840	0.685 ± 0.773	0.715 ± 0.790	0.891 ± 0.813	0.831 ± 0.821	0.887 ± 0.808
OCSVM	0.479 ± 0.599	0.589 ± 0.705	0.745 ± 0.790	0.632 ± 0.752	0.694 ± 0.782	0.760 ± 0.775	0.695 ± 0.737	0.818 ± 0.806
FALSE POSITIVE COST = 1, FALSE NEGATIVE COST = 10, REJECTION COST = min{1-γ,10γ}
AE	0.730 ± 0.747	0.761 ± 0.756	0.909 ± 0.882	0.784 ± 0.825	0.780 ± 0.805	0.819 ± 0.843	0.789 ± 0.825	0.797 ± 0.821
COPOD	0.761 ± 0.767	0.765 ± 0.770	0.930 ± 0.888	0.794 ± 0.805	0.800 ± 0.801	0.844 ± 0.842	0.802 ± 0.815	0.827 ± 0.832
ECOD	0.739 ± 0.759	0.767 ± 0.766	0.900 ± 0.858	0.789 ± 0.811	0.788 ± 0.787	0.840 ± 0.839	0.791 ± 0.803	0.821 ± 0.819
GMM	0.670 ± 0.676	0.765 ± 0.767	0.845 ± 0.782	0.754 ± 0.755	0.739 ± 0.736	0.785 ± 0.757	0.760 ± 0.753	0.766 ± 0.750
HBOS	0.687 ± 0.684	0.776 ± 0.782	0.824 ± 0.808	0.750 ± 0.768	0.744 ± 0.747	0.785 ± 0.787	0.749 ± 0.765	0.753 ± 0.766
IFOR	0.679 ± 0.680	0.775 ± 0.776	0.847 ± 0.824	0.755 ± 0.771	0.743 ± 0.745	0.761 ± 0.772	0.757 ± 0.774	0.763 ± 0.770
INNE	0.660 ± 0.685	0.772 ± 0.779	0.695 ± 0.620	0.774 ± 0.742	0.748 ± 0.722	0.758 ± 0.737	0.744 ± 0.716	0.773 ± 0.754
KDE	0.691 ± 0.692	0.791 ± 0.773	0.887 ± 0.836	0.754 ± 0.760	0.755 ± 0.744	0.785 ± 0.807	0.758 ± 0.754	0.759 ± 0.760
KNN	0.706 ± 0.657	0.767 ± 0.764	0.839 ± 0.779	0.791 ± 0.736	0.769 ± 0.710	0.778 ± 0.736	0.799 ± 0.736	0.803 ± 0.729
LODA	0.750 ± 0.714	0.781 ± 0.775	0.880 ± 0.850	0.811 ± 0.768	0.806 ± 0.761	0.804 ± 0.783	0.827 ± 0.780	0.838 ± 0.784
LOF	0.738 ± 0.679	0.764 ± 0.764	0.999 ± 0.833	0.826 ± 0.757	0.810 ± 0.739	0.871 ± 0.770	0.867 ± 0.799	0.846 ± 0.747
OCSVM	0.730 ± 0.711	0.780 ± 0.774	0.953 ± 0.878	0.791 ± 0.786	0.795 ± 0.773	0.845 ± 0.833	0.787 ± 0.772	0.796 ± 0.783
FALSE POSITIVE COST = 5, FALSE NEGATIVE COST = 5, REJECTION COST = γ
AE	0.534 ± 0.611	0.618 ± 0.666	0.671 ± 0.716	0.644 ± 0.741	0.655 ± 0.736	0.707 ± 0.748	0.705 ± 0.740	0.738 ± 0.762
COPOD	0.545 ± 0.619	0.627 ± 0.673	0.676 ± 0.724	0.629 ± 0.674	0.666 ± 0.716	0.719 ± 0.747	0.719 ± 0.730	0.731 ± 0.739
ECOD	0.529 ± 0.609	0.625 ± 0.675	0.629 ± 0.687	0.638 ± 0.702	0.662 ± 0.705	0.701 ± 0.736	0.708 ± 0.716	0.724 ± 0.727
GMM	0.534 ± 0.599	0.626 ± 0.687	0.719 ± 0.709	0.656 ± 0.716	0.675 ± 0.720	0.776 ± 0.736	0.746 ± 0.731	0.780 ± 0.743
HBOS	0.499 ± 0.572	0.622 ± 0.694	0.632 ± 0.661	0.650 ± 0.669	0.641 ± 0.681	0.695 ± 0.706	0.688 ± 0.686	0.710 ± 0.709
IFOR	0.497 ± 0.569	0.623 ± 0.677	0.643 ± 0.680	0.620 ± 0.667	0.629 ± 0.692	0.696 ± 0.712	0.688 ± 0.701	0.714 ± 0.719
INNE	0.491 ± 0.569	0.617 ± 0.668	0.622 ± 0.572	0.718 ± 0.691	0.691 ± 0.674	0.709 ± 0.685	0.705 ± 0.675	0.726 ± 0.698
KDE	0.562 ± 0.639	0.642 ± 0.673	0.709 ± 0.739	0.666 ± 0.711	0.684 ± 0.726	0.748 ± 0.742	0.679 ± 0.689	0.761 ± 0.742
KNN	0.521 ± 0.544	0.628 ± 0.677	0.687 ± 0.667	0.657 ± 0.646	0.634 ± 0.651	0.701 ± 0.664	0.693 ± 0.657	0.728 ± 0.664
LODA	0.550 ± 0.595	0.627 ± 0.677	0.601 ± 0.649	0.670 ± 0.668	0.665 ± 0.680	0.708 ± 0.698	0.683 ± 0.645	0.757 ± 0.711
LOF	0.554 ± 0.580	0.628 ± 0.681	0.809 ± 0.737	0.678 ± 0.682	0.674 ± 0.688	0.792 ± 0.703	0.759 ± 0.718	0.788 ± 0.698
OCSVM	0.523 ± 0.582	0.631 ± 0.671	0.704 ± 0.728	0.634 ± 0.685	0.657 ± 0.695	0.709 ± 0.704	0.660 ± 0.674	0.733 ± 0.716