Chapter 8 for AP Stats

Front

What is the formula for constructing a confidence interval using a statistic, critical value, and standard deviation?

Back

.426 ± (1.96) * (.031)

Front

How do you interpret a confidence interval?

Back

We are 95% confident that the interval from .375 to .478 captures the actual value of the population parameter.

Front

What does a confidence level of 95% mean in terms of sample intervals?

Back

95% of all possible samples of a given size from a population will result in an interval that captures the unknown parameter.

Front

What is the correct t* value for a confidence level of 98% with a sample size of 22?

Back

InvT(.99, 21) = 2.518

Front

How do you determine the sample size needed for a specific margin of error in a confidence interval for population means?

Back

Use the formula z* ( σ/ (√n) ) ≤ ME.

Front

What is a critical value in the context of confidence intervals?

Back

A critical value is a factor used to compute the margin of error, based on the desired confidence level.

Front

What does the standard deviation represent in the context of confidence intervals?

Back

The standard deviation measures the amount of variation or dispersion in a set of values.

Front

What is the relationship between sample size and margin of error in confidence intervals?

Back

As the sample size increases, the margin of error decreases, leading to a more precise confidence interval.

Front

What is the significance of the 95% confidence level in statistics?

Back

It indicates that if we were to take 100 different samples and compute a confidence interval for each sample, approximately 95 of the intervals would contain the true population parameter.

Front

How do you calculate the margin of error for a confidence interval?

Back

Margin of Error = Critical Value * Standard Deviation.