Any function and its inverse are symmetrical about the line\(y = x\).

All quadratic functions have the same type of curved graphs with a line of symmetry. The graph of the quadratic function \(y = ax^2 + bx + c \) has a minimum turning point when \(a \textgreater 0 \) ...

The Annals of Statistics, Vol. 37, No. 3 (Jun., 2009), pp. 1360-1404 (45 pages) We study the problem of nonparametric estimation of a multivariate function $g ...