Estimation and Confidence Intervals skill check
Point estimates, standard errors, margins of error, z and t intervals, proportion intervals (Wald and Wilson), Welch, paired and difference-in-proportion intervals, sample-size planning and the bootstrap — calculated on fresh numbers and interpreted correctly. 12 questions, 30 minutes, 70% to pass.
- Questions
- 12
- Time
- 30 min
- Pass mark
- 70%
- Retake after
- 6 h
Skills covered
Choose and calculate a point estimate · Judge an estimator by bias and variability · Calculate a standard error · Calculate and use a margin of error · Explain what makes an interval wider or narrower · Find the critical value for a confidence level · Build a z interval for a mean · Build a t interval for a mean · Choose between z and t, and explain why · Interpret a confidence interval correctly · Explain the coverage of a confidence procedure · Build an interval for a proportion · Choose between Wald and Wilson intervals · Build a Welch interval for a difference in means · Build an interval from paired data · Build an interval for a difference in proportions · Plan the sample size for a mean · Plan the sample size for a proportion · Build a percentile bootstrap interval · Judge when the bootstrap can be trusted
Covers Track 7: Estimation and Confidence Intervals. Passing it, together with completing every lesson, earns the track certificate.
How it works
- Questions are drawn from this assessment's own bank, with numbers generated for your attempt.
- Your answers save automatically. Nothing is graded until you submit or the time runs out (the server keeps the time).
- No hints or feedback during the attempt; full worked solutions afterwards.
- You may use a calculator, the lab and your notes. The assessment is not proctored.