Inference for Proportions 1

Front

What alpha level is assumed if no alpha level is given?

Back

0.05

Front

What are the results of Type I and Type II errors for the hypotheses: Ho: The weather will remain dry. Ha: It will rain?

Back

Type I: Needlessly carry around an umbrella all day. Type II: Get drenched.

Front

What do the null and alternative hypotheses divide all possibilities into?

Back

Two non-overlapping sets.

Front

What additional condition must be checked for a 2-proportion test compared to a 1-proportion test?

Back

You must make sure that the two samples are independent from one another.

Front

What was the p^ value used to determine a 99% confidence interval of (0.785, 0.831) for the proportion of teens who drink coffee every day?

Back

0.808

Front

Define null hypothesis (Ho).

Back

A statement that there is no effect or no difference, and it is the hypothesis that researchers aim to test against.

Front

Define alternative hypothesis (Ha).

Back

A statement that indicates the presence of an effect or a difference, opposing the null hypothesis.

Front

What is a Type I error?

Back

Rejecting the null hypothesis when it is actually true.

Front

What is a Type II error?

Back

Failing to reject the null hypothesis when it is actually false.

Front

What is the purpose of a confidence interval?

Back

To estimate the range within which a population parameter lies with a certain level of confidence.