Confidence Intervals

Question 1

Determine whether this is a means or a proportions problem.

Accepted Answer

Proportions

Question 2

Determine if this is a means or a proportions problem.

Accepted Answer

Means

Question 3

Determine whether or not this is a means problem or a proportions problem.

Accepted Answer

Means

Question 4

As the confidence level increases, the confidence interval gets __________.

Accepted Answer

wider

Question 5

As the sample size increases, the confidence interval gets __________.

Accepted Answer

narrower

Question 6

Determine what distribution to use, if any.

Accepted Answer

Neither

Question 7

Identify the Critical value for a 95% confidence interval.

Accepted Answer

2.447

Question 8

Determine the critical value for a 90% confidence interval

Accepted Answer

1.645

Question 9

We use the t-distribution when...

Accepted Answer

σ is unknown

Question 10

A confidence interval is the ____________ plus or minus the __________ .

Accepted Answer

Point Estimate, Margin of Error

Question 11

Determine which distribution to use, if any.

Accepted Answer

t-distribution

Question 12

-12.56 < μ1 - μ2 < -5.38 is a 95% confidence interval. Which is true about the pop. means?

Accepted Answer

μ1 < μ2

Question 13

Check to see if the conditions are met in order to create a confidence interval.

Accepted Answer

Yes, because np̂ ≥ 5 and nq̂ ≥ 5

Questions 13