Exam 11: The T Test for Two Related Samples

A researcher obtains t(20) = 2.00 and M_D = 9 for a repeated-measures study.If the researcher measures effect size using the percentage of variance accounted for, what value will be obtained for r²?

The following data were obtained from a repeated-measures research study.What is the value of M_D for these data?

A repeated?measures test usually is more likely to detect a real treatment effect than an independent?measures test because the repeated?measures design typically has a smaller variance and a smaller estimated standard error.

A research report describing the results from a repeated-measures t test states, "t(22) = 1.71, p > .05." From this report you can conclude that the outcome of the hypothesis test was ______.

For a repeated-measures study, a small variance for the difference scores indicates that the treatment has little or no effect.

A repeated-measures research study uses a total of 20 participants to compare two treatment conditions.If the results are used to construct a 90% confidence interval for the population mean difference, then the t values will be ±1.729.

For a research study comparing two treatment conditions, a repeated-measures design would require two scores for each participant but an independent-measures design would require only one score for each participant.

For the following data from a repeated-measures study, the sample mean difference is M_D = 4.

Repeated-measures designs are particularly well-suited to research questions concerning the difference between two distinct populations (for example, males versus females).

For a repeated-measures design, the sample mean difference is always located exactly in the center of the confidence interval estimate for the population mean difference.

The null hypothesis for a repeated-measures test states:

In a repeated-measures study comparing two treatments with a sample of n = 15 participants, the researcher measures two scores for each individual to obtain a total of 30 scores.The repeated-measures t statistic for this study has df = 29.

A repeated-measures study and an independent-measures study both produce a t statistic with df = 20.The repeated-measures study used more subjects than the independent-measures study.

Compared to an independent-measures design, a repeated-measured study is more likely to find a significant effect because it reduces the contribution of variance due to ______.

A set of n = 16 difference scores has a mean of M_D = 4 and a variance of s² = 36.Cohen's d for this sample is d = 4/6.

Assuming that other factors are held constant, which of the following would tend to increase the likelihood of rejecting the null hypothesis?

A researcher would like to compare two treatment conditions with a set of 30 scores in each treatment.If a repeated-measures design is used, the study will require n = 60 participants.

If a set of n = 9 difference scores has a mean of M_D = 3.5 and a variance of s² = 36, then the sample will produce a repeated-measures t statistic of t = 3.5/2.

A researcher is using a repeated-measures study to evaluate the difference between two treatments.If the difference between the treatments is consistent from one participant to another, then the data should produce ______.

A matched-subjects study and an independent-measures study both produced a t statistic with df = 16.How many individuals participated in each study?