AP Statistics / Unit 3: Inference for Categorical Data: Proportions

3.11 Justifying a Claim Based on a Confidence Interval for the Difference Between Two Population Proportions

3 practice questions

Notes

If the interval for $p_1-p_2$ contains 0, "no difference" is plausible.
If it's entirely above 0, there's convincing evidence $p_1>p_2$.

Practice

A 95% CI for $p_1-p_2$ is $(0.03, 0.12)$. This suggests:

A 95% CI for $p_1-p_2$ is $(-0.04, 0.08)$:

An interval of $(-0.15,-0.02)$ suggests:

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