Exam 9: Testing the Difference Between Two Means

When reporting the results of a t-statistic, the researcher should include information about the inferential statistics such as the calculated t, degrees of freedom, value of the statistic and the significance level.

A study compares the means of two groups, each having N = 20. If the standard deviations of the two groups are 10.00 and 6.00, what is the value for the standard error of the difference ?

A researcher hypothesizes that children from middle class families have higher education levels than children from lower class families. In conducting an analysis to test this hypothesis, how might the alternative hypothesis be stated?

A study compares the means of two groups, each having N = 15. If the standard deviations of the two groups are 1.67 and 2.98, what is the value for the standard error of the difference ?

The ______ of the sampling distribution of the difference is equal to ______.

The within-subjects research design tests differences ______.

The smaller the ______, the ______ likely you are to reject the null hypothesis.

For a group of 30 participants, how many degrees of freedom are there for a t-test for dependent means?

A ______ symbol is part of the ______ hypothesis, and implies this hypothesis is ______.

In making the decision to reject H₀, what happens if you set α at .10 rather than .05?

In conducting the t-test for independent means, if you ______, the two means ______.

A marriage counselor wishing to compare the values of married couples collects data from 10 husbands and their wives. Which type of statistical analysis should she use to analyze this data?

A researcher conducts a study measuring 20 children before and after they play violent video games and obtains a value of 1.98 for the t-statistic. For a non-directional alternative hypothesis, which of the following is the correct way to present this analysis?

A researcher comparing the means of two groups calculates the t-test for independent means and reports the following result: t(22) = -3.54, p <.01. This research study consisted of a TOTAL of ______ participants.

Which of the following null hypotheses would result in calculating the t-test for a single mean?

The larger the ______, the ______ likely you are to reject the null hypothesis.

In testing the difference between two means, which of these is implied by the null hypothesis (H₀)?

What happens when you change α from .05 to .10?

What is the value of X_D for the following set of five difference (D) scores: -6, 1, -7, -3, -13?

You ______ the null hypothesis when the value of the statistic falls in the region of ______ because this means ______.