Extremum estimator

An extremum estimator ${\widehat {\theta }}_{E}$ is an estimator of a model parameter that achieves an extreme value of a specified criterion function.

For example, in econometrics ${\widehat {\theta }}_{E}={\underset {{\widehat {\theta }}\in \Theta }{\operatorname {arg\,inf} }}Q_{n}({\widehat {\theta _{n}}})$, where $Q_{n}({\widehat {\theta _{n}}})\leq {\underset {{\widehat {\theta }}\in \Theta }{\operatorname {\,inf} }}Q_{n}({\widehat {\theta }})+Op(1)$.

See also

Op (statistics)