# Question: Using se see Exercise 14 18 instead of rewrite

Using se (see Exercise 14.18) instead of , rewrite

(a) The expression for t in Theorem 14.4;

(b) The confidence interval formula of Theorem 14.5.

Exercise 14.18

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) The expression for t in Theorem 14.4;

(b) The confidence interval formula of Theorem 14.5.

Exercise 14.18

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.

## Answer to relevant Questions

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