Exam 10: T Test for Correlated Groups Samples

A researcher believes exercise reduces anxiety in women. She identifies a group of women who had not exercised before but are now planning to begin exercising. She gives them a 50-item anxiety inventory before they begin exercising and administers it again after six months of exercising. The anxiety inventory is measured on an interval scale and higher numbers indicate higher anxiety. In addition, scores on the inventory are normally distributed. The scores are given below. -Should H₀ be rejected? What should the researcher conclude?

A researcher believes exercise reduces anxiety in women. She identifies a group of women who had not exercised before but are now planning to begin exercising. She gives them a 50-item anxiety inventory before they begin exercising and administers it again after six months of exercising. The anxiety inventory is measured on an interval scale and higher numbers indicate higher anxiety. In addition, scores on the inventory are normally distributed. The scores are given below. -Calculate the 95% CI.

A researcher believes exercise reduces anxiety in women. She identifies a group of women who had not exercised before but are now planning to begin exercising. She gives them a 50-item anxiety inventory before they begin exercising and administers it again after six months of exercising. The anxiety inventory is measured on an interval scale and higher numbers indicate higher anxiety. In addition, scores on the inventory are normally distributed. The scores are given below. -If significant, compute the effect size and interpret this.

If the null hypothesis is not supported, then the t test should be:

A researcher believes exercise reduces anxiety in women. She identifies a group of women who had not exercised before but are now planning to begin exercising. She gives them a 50-item anxiety inventory before they begin exercising and administers it again after six months of exercising. The anxiety inventory is measured on an interval scale and higher numbers indicate higher anxiety. In addition, scores on the inventory are normally distributed. The scores are given below. -Identify H₀ and H_a for this study.

A researcher believes exercise reduces anxiety in women. She identifies a group of women who had not exercised before but are now planning to begin exercising. She gives them a 50-item anxiety inventory before they begin exercising and administers it again after six months of exercising. The anxiety inventory is measured on an interval scale and higher numbers indicate higher anxiety. In addition, scores on the inventory are normally distributed. The scores are given below. -If significant, draw a graph representing the data.

If a researcher reported for a correlated-groups t test that t(22) = 2.69, p < .01, how many subjects were there in the study?

A correlated-groups t test:

A researcher believes exercise reduces anxiety in women. She identifies a group of women who had not exercised before but are now planning to begin exercising. She gives them a 50-item anxiety inventory before they begin exercising and administers it again after six months of exercising. The anxiety inventory is measured on an interval scale and higher numbers indicate higher anxiety. In addition, scores on the inventory are normally distributed. The scores are given below. -Conduct the appropriate analysis.

If a researcher reported for a correlated-groups t test that t(18) = 2.90, p < .01, how many subjects were there in the study?

If a correlated-groups t test and an independent-groups t test both have df = 16, which experiment used more subjects?

If a researcher reported for a correlated-groups t test that t(12) = 3.66, p < .01, how many subjects were there in the study?

Imagine that you conducted a correlated-groups t test with 7 subjects. For a two-tailed test, the t_cv at $\alpha$ = .05 would be:

In the formula to compute the correlated-groups t test, the denominator in the equation represents:

If a correlated-groups t test and an independent-groups t test both have df = 16, how many subjects were in each study?

A researcher believes exercise reduces anxiety in women. She identifies a group of women who had not exercised before but are now planning to begin exercising. She gives them a 50-item anxiety inventory before they begin exercising and administers it again after six months of exercising. The anxiety inventory is measured on an interval scale and higher numbers indicate higher anxiety. In addition, scores on the inventory are normally distributed. The scores are given below. -What statistical test should be used to analyze these data?

After calculating a correlated-groups t test, if you find that it is equal to zero, then:

If the null hypothesis is true, then the t test should be close to: