<Dl> <Dd> SE x _̄ = σ n (\ displaystyle (\ text (SE)) _ (\ bar (x)) \ = (\ frac (\ sigma) (\ sqrt (n)))) </Dd> </Dl> <Dd> SE x _̄ = σ n (\ displaystyle (\ text (SE)) _ (\ bar (x)) \ = (\ frac (\ sigma) (\ sqrt (n)))) </Dd> <Dl> <Dd> σ is the standard deviation of the population . </Dd> <Dd> n is the size (number of observations) of the sample . </Dd> </Dl> <Dd> σ is the standard deviation of the population . </Dd>

What is a point estimate of the error standard deviation σ