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Sets","pinned":false,"hidden":false,"mode":"md","author":"$undefined","summary":"$undefined","tool":"$undefined","providerMetadata":"$undefined","attachments":"$undefined","output":"","database":"$undefined"},{"id":14,"value":"1\\. From a sample of 20 users where 16 completed the task successfully, the completion rate was 80%. Using the Adjusted Wald method, the 95% confidence interval is 57.82% to 92.51%.\n\n \n ","pinned":false,"hidden":false,"mode":"md","author":"$undefined","summary":"$undefined","tool":"$undefined","providerMetadata":"$undefined","attachments":"$undefined","output":"","database":"$undefined"},{"id":18,"value":"

","pinned":false,"hidden":false,"mode":"html","author":"$undefined","summary":"$undefined","tool":"$undefined","providerMetadata":"$undefined","attachments":"$undefined","output":"","database":"$undefined"},{"id":24,"value":"2\\. From a sample of 23 users where 19 completed the task successfully, the completion rate was 82.61%. The 90% confidence interval using the Adjusted Wald method is 66.00% to 92.35%, while the Exact method gives 64.51% to 93.83%. The Adjusted Wald method is generally the better choice because its coverage is closer to the intended confidence level while producing a narrower interval. The Exact method is more conservative, meaning it tends to produce wider intervals in order to guarantee at least the specified coverage.","pinned":false,"hidden":false,"mode":"md","author":"$undefined","summary":"$undefined","tool":"$undefined","providerMetadata":"$undefined","attachments":"$undefined","output":"","database":"$undefined"},{"id":70,"value":"

","pinned":false,"hidden":false,"mode":"html","author":"$undefined","summary":"$undefined","tool":"$undefined","providerMetadata":"$undefined","attachments":"$undefined","output":"","database":"$undefined"},{"id":50,"value":" 5\\. Using the task-time calculator with the 40 task times, the 95% confidence interval is 71.6 to 106.7 seconds, and the median is 108.5 seconds. I noticed that the median and geometric mean were much farther apart in this problem than in the earlier examples, where the median and geometric mean were so close that the difference was not very noticeable. The MeasuringU website explicitly states that its calculator uses the geometric mean to calculate the confidence interval, which explains why the median falls outside the confidence interval.
\nn = 40
\nMedian = 108.5 sec
\nGeometric mean = 87.42 sec
\n95% CI = 71.6 - 106.7 sec","pinned":false,"hidden":false,"mode":"md","author":"$undefined","summary":"$undefined","tool":"$undefined","providerMetadata":"$undefined","attachments":"$undefined","output":"","database":"$undefined"},{"id":56,"value":"

","pinned":false,"hidden":false,"mode":"html","author":"$undefined","summary":"$undefined","tool":"$undefined","providerMetadata":"$undefined","attachments":"$undefined","output":"","database":"$undefined"},{"id":58,"value":"7\\. Using the continuous-data calculator with the 16 scores, the average score is 7.69, with a 95% confidence interval of 6.68 to 8.69. I can't be confident that the average score for the population would fall in the promoter range because promoters give scores of 9 or 10, and the entire confidence interval falls below 9. This means the population average could plausibly fall anywhere between 6.68 and 8.69, which is below the promoter threshold.
\nn = 16
\nmean = 7.69
\nStandard deviation = 1.89
\nStandard error = 0.473
\n95% CI = 6.68 - 8.69\n","pinned":false,"hidden":false,"mode":"md","author":"$undefined","summary":"$undefined","tool":"$undefined","providerMetadata":"$undefined","attachments":"$undefined","output":"","database":"$undefined"},{"id":108,"value":"

","pinned":false,"hidden":false,"mode":"html","author":"$undefined","summary":"$undefined","tool":"$undefined","providerMetadata":"$undefined","attachments":"$undefined","output":"","database":"$undefined"},{"id":60,"value":"8\\. Using the continuous-data calculator with the 10 SUS scores, the average score is 56.05, with a 90% confidence interval of 47.45 to 64.65. Based on this sample, the average score for the population could plausibly fall within this range. This suggests that the university website’s perceived usability is likely below the commonly used SUS benchmark of 68.
\nn = 10
\nmean = 56.05
\nStandard deviation = 14.83
\nStandard error = 4.69
\n90% CI = 47.45 - 64.65
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