# Question: Show that a 2 the random variable corresponding to 2

Show that

(a) ∑2, the random variable corresponding to 2, is not an unbiased estimator of σ2;

(b) S2e = n·∑2 / n–2 is an unbiased estimator of σ2. The quantity se is often referred to as the standard error of estimate.

(a) ∑2, the random variable corresponding to 2, is not an unbiased estimator of σ2;

(b) S2e = n·∑2 / n–2 is an unbiased estimator of σ2. The quantity se is often referred to as the standard error of estimate.

## Relevant Questions

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