Chebyshev center
In geometry, the Chebyshev center of a bounded set Q {\displaystyle Q} having non-empty interior is the center of the minimal-radius ball enclosing the entire set Q {\displaystyle Q} , or alternatively (and non-equivalently) the center of largest inscribed ball of Q {\displaystyle Q} . In the field of parameter estimation, the Chebyshev center approach tries to find an estimator x ^ {\displaystyle {\hat {x}}} for x {\displaystyle x} given the feasibility set Q {\displaystyle Q} , such that x ^ {\displaystyle {\hat {x}}} minimizes the worst possible estimation error for x (e.g.