With b = 2, SE(b) = 0.4, n = 20 (df = 18, t ≈ 2.101), 95% CI for β is

(1.16, 2.84) ME = 2.101·0.4 ≈ 0.84; CI = (1.16, 2.84).

Confidence Intervals for the Slope of a Regression Model

AP Statistics· difficulty 4/5

With b = 2, SE(b) = 0.4, n = 20 (df = 18, t* \approx 2.101), 95% CI for β is

Explanation

ME = 2.101\cdot0.4 \approx 0.84; CI = (1.16, 2.84).

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