To quantify the improvement of EQI for two objectives, two criteria of MO-E-EQI are illustrated in Figure by plotting a Pareto front set against two objectives. The horizontal and vertical solid lines represent the Pareto front. The expected improvement is calculated by using the probability of improvement (area of hatched area) and Euclidian distance between the centroid of the area and each member in the Pareto set . If a new point falls into the hatched area, it will dominate and replace at least one current member in the Pareto set, whereas if it is placed in the shaded hatched area, it will augment current Pareto solutions. Therefore, by changing the area of integration, MO-E-EQI can change between an aggressive setting by adding fewer points on the Pareto front, or a non-aggressive setting by adding more in-between points. Appendix B describes detailed steps of the algorithm.