文摘
We derive new bounds for the smallest valuexminand the largest valuexmaxof a finite samplex1,…,xnof real numbers. Our bounds are obtained by solving two optimization problems, one of them being convex and the other nonconvex. We show that the pair (xmin,xmax) lies in a region bounded by an ellipse and an hyperbola. The corresponding cartesian equations are given in terms of the average and the standard deviation of the sample.