##  [Cramér–Rao Bound](/cramer-rao-bound) 

  ##  [Cramér–Rao Bound](https://natural.quantumdictionary.io/cramer-rao-bound-0) 

  

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**Natural & Formal Sciences Dictionary**

 







 

 

 

 



 

 

 

 

Definition

A lower bound on the variance of any unbiased estimator of a parameter, given by the inverse of the Fisher information: Var(θ̂) ≥ 1 / I(θ).