Practice Problems: Confidence Intervals
A university wants to know more about the knowledge of students regarding international events. The are concerned that their students are uninformed in regards to new from other countries. A standardized test is used to assess students knowledge of world events (national reported mean=65, S=5). A sample of 30 students are tested (sample mean=58, Standard Error=3.2). Compute a 99 percent confidence interval based on this sample's data. How do these students compare to the national sample?
Confidence Interval at the 99 percent: 49.2 < population mean < 66.8
While the data for these students are low in relation to the national scores, the constucted interval does include the national mean. Therefore, the university may be on par with other universities. The university may with to replicate their survey to further validate their results.
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