Interpret a Confidence Interval

In a survey of 104 students, it was found that 79 went to the homecoming game this year. A 99% confidence interval for p is (0.652, 0.868). Interpret this interval.

• 99% of the time the true proportion of people who went to the homecoming game this year is between 65.2% and 86.6%.

• The probability that the population proportion of people who went to the homecoming game this year is between 65.2% and 86.6% is 95%.

• Based on this sample, I am 99% confident that the true proportion of people who went to the homecoming game this year is between 65.2% and 86.6%.

• 99% of all possible intervals calculated this way will capture the true proportion of people who went to the homecoming game this year

This is notation from a different book. Identify the confidence interval used in the figure below if each shaded area is equal to 0.05.

• 90%

• 95%

• 98%

• 99%

Identify the confidence interval used in the figure below if each shaded area is equal to 0.05.

• 90%

• 95%

• 98%

• 99%

A 95% confidence interval was conducted on American adults aged 45-64 and found that the between 15.7% and 19.4% had diabetes as of 2016. a) What is the population proportion that has diabetes according to this confidence interval? ​ (a)   b) What was the margin of error associated with this data? ​ (b)  

• 17.55%

• 1.85%

• 11.55

• 5.775

• 11.55%

• 5.775%

What is the main purpose of using a 95% confidence interval in statistics?

• To estimate the range within which the true population parameter lies with 95% certainty.

• To confirm the exact value of the population mean.

• To calculate the standard deviation of the sample.

• To determine if the sample data is normally distributed.

• A
• B
• C
• D

Percentiles of the bootstrap distribution are provided. Use the percentiles to report a 95% confidence interval for the parameter.

• 6.593 hours to 7.78 hours

• 6.322 hours to 8.082 hours

• 6.438 hours to 7.947 hours

• 6.174 hours to 8.304 hours

Interpret the following confidence interval.

• We are 95% confident the true population mean lies between 10 and 30.

• There is a 95% chance the true population mean lies between 10 and 30.

• 95% of samples will have a mean between 10 and 30.

• The true population mean lies between 10 and 30 95% of the time.

Identify the point estimate from the given confidence interval.

• 4

• 7

• 10

• 14

Identify the margin of error from the given confidence interval.

• 2

• 8

• 10

• 12