Review Confidence interval Intro

A random sample of residents in city J were surveyed about whether they supported raising taxes to increase bus service for the city. From the results, a 95 percent confidence interval was constructed to estimate the proportion of people in the city who support the increase. The interval was (0.46,0.52). What is the point estimate?

• 0.49

• 0.04

• 0.08

• 0.98

• 0.06

Tags

CCSS.HSS.IC.B.4

A random sample of residents in city J were surveyed about whether they supported raising taxes to increase bus service for the city. From the results, a 95 percent confidence interval was constructed to estimate the proportion of people in the city who support the increase. The interval was (0.46,0.52). What is the margin of error?

• 0.49

• 0.04

• 0.08

• 0.98

• 0.06

Tags

CCSS.HSS.IC.B.4

A random sample of residents in city J were surveyed about whether they supported raising taxes to increase bus service for the city. From the results, a 95 percent confidence interval was constructed to estimate the proportion of people in the city who support the increase. The interval was (0.46,0.52). Which statement correctly interprets the 95% interval in context?

• There is a 95% chance that the interval (0.46,0.52) contains the true proportion of peopl in the city who support the increase

• We are 95% confident that the true proportion of people in the city who support the increase is captured in the interval (0.46,0.52)

• If we take many samples, about 95% of them will contain the interval (0.46,0.52)

• There is a 95% probability that the interval (0.46,0.52) contains the true proportion of people in the city who support the increase

• The probability that the interval (0.46,0.52) captures P is either 0 or 1, but we don’t know which.

Tags

CCSS.HSS.IC.B.4

A random sample of residents in city J were surveyed about whether they supported raising taxes to increase bus service for the city. From the results, a 95 percent confidence interval was constructed to estimate the proportion of people in the city who support the increase. The interval was (0.46,0.52). Which statement correctly interprets the 95% level in context?

• There is a 95% chance that the interval (0.46,0.52) contains the true proportion of peopl in the city who support the increase

• We are 95% confident that the true proportion of people in the city who support the increase is captured in the interval (0.46,0.52)

• If we take many samples, about 95% of them will contain the interval (0.46,0.52)

• There is a 95% probability that the interval (0.46,0.52) contains the true proportion of people in the city who support the increase

• The probability that the interval (0.46,0.52) captures P is either 0 or 1, but we don’t know which.

Tags

CCSS.HSS.IC.B.4

A random sample of 10 employees of a company was selected to estimate the mean one-way commute time for all employees at the company. A 90% confidence interval found a point estimate of 38 and margin of error of 3.5. What is the parameter of interest?

A random sample of 10 employees of a company was selected to estimate the mean one-way commute time for all employees at the company. A 90% confidence interval found a point estimate of 38 and margin of error of 3.5. Calculate the 90% confidence interval.

What would happen to the interval if we increased the sample size?

• Everything would stay the same

• The Margin of Error would increase

• The Margin of Error would decrease

• The point estimate would increase

• The point estimate would decrease

Tags

CCSS.HSS.IC.B.4

What would happen to the interval if we calculated a 95% confidence interval instead?

• Everything would stay the same

• The Margin of Error would increase

• The Margin of Error would decrease

• The point estimate would increase

• The variability would increase

Tags

CCSS.HSS.IC.B.4

Do we have convincing evidence that most commuters have over a 30 minute commute?

• Yes because the entire interval is above 30

• No because the entire interval is below 30

• No because 30 is in the interval

• Yes because 30 is in the interval

Tags

CCSS.HSS.IC.B.4