# Question

1. + 2se ()

2. ŷ ± se (p̂)

3. 2se (X-bar)

4. N (μ, σ2 / n)

5. s / √n

6. σ / √n

7. 1 / (0.05)2

8. [0,1]

9. √ p̂ (1 – p̂) / n

10. t0.025 n–1

(a) Sampling distribution of X–bar

(b) Margin of error

(c) 100% confidence interval for p

(d) Estimated standard error of Y-bar

(e) Estimated standard error of p̂

(f) An interval with about 95% coverage

(g) Actual standard error of Y-bar

(h) About 2 for moderate sample sizes

(i) An interval with 68% coverage

(j) Sample size needed for 0.05 margin of error

2. ŷ ± se (p̂)

3. 2se (X-bar)

4. N (μ, σ2 / n)

5. s / √n

6. σ / √n

7. 1 / (0.05)2

8. [0,1]

9. √ p̂ (1 – p̂) / n

10. t0.025 n–1

(a) Sampling distribution of X–bar

(b) Margin of error

(c) 100% confidence interval for p

(d) Estimated standard error of Y-bar

(e) Estimated standard error of p̂

(f) An interval with about 95% coverage

(g) Actual standard error of Y-bar

(h) About 2 for moderate sample sizes

(i) An interval with 68% coverage

(j) Sample size needed for 0.05 margin of error

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