Stats - Ch. 9 Quiz

To determine which of two methods for learning a motor skill is more effective, the correct statistical analysis is A. an independent t test B. multiple regression C. a Spearman rank-difference correlation D. a dependent t test

A. an independent t test

When the purpose of the research is to determine the effects of one independent variable (e.g., four groups) on one dependent variable (e.g., self-concept), the best choice of a statistical analysis is A. analysis of variance B. multiple t tests C. discriminant analysis D. MANOVA

A. analysis of variance

Use of a one-tailed versus a two-tailed test of significance of the difference between two sample means depends on A. whether the difference is expected to be in one direction only B. the size of the samples relative to population size C. whether the participants were matched or chosen randomly D. whether there is expected overlap between the error curves of the two sample distributions

A. whether the difference is expected to be in one direction only

When the purpose of the research is to evaluate the effects of an independent variable on a dependent variable while controlling the influence of another characteristic, the best choice of a statistical analysis is A. analysis of variance B. analysis of covariance C. discriminant analysis D. multiple regression

B. analysis of covariance

If ANOVA has found a significant difference among four treatment groups, a follow-up test such as the Scheffé is needed to determine A. whether the F ratio is significantly different from chance B. which of the groups differ significantly from the others C. the percentage of variance accounted for by the treatments

B. which of the groups differ significantly from the others (pg 301)

Which one of the following statements does not describe an advantage of repeated measures? A. Repeated measures are more economical because fewer participants are needed. B. Repeated measures control for individual differences among participants. C. Repeated measures can eliminate the influence of some unwanted variable D. Repeated measures allow the researcher to study a phenomenon across time.

C. Repeated measures can eliminate the influence of some unwanted variable

If the null hypothesis is false, one may assume the research hypothesis is the explanation for the results if A. there is no experimenter bias B. there is a reasonable number of participants in each group C. all other possible explanations have been controlled D. p < .05

C. all other possible explanations have been controlled

A researcher sought to find out which of two exercises was more effective in building endurance. One group used exercise A, and another group used exercise B. At the end of study, the researcher should compare the two groups' scores by A. the Spearman rank-difference correlation B. a dependent t test C. an independent t test D. multiple regression

C. an independent t test

A researcher wishes to determine whether a treatment group made a significant improvement from the pretest (M = 25) to the posttest (M = 30). The correct statistical test to use to compare the two means is the A. independent t test B. Pearson r C. dependent t test D. Spearman r

C. dependent t test

A researcher used a t test to compare treatments and obtained a t of 3.45. One group had 48 participants, and the other group had 40. The table value for significance at the .01 level was 2.64. Which of the following is the correct way to express these results? A. t(40, 48) = 2.64, p > .01 B. t(88) = 3.45, p < .01 C. t(2, 86) = 3.45, p < .01 D. t(86) = 3.45, p < .01

D. t(86) = 3.45, p < .01

The t test is used to A. estimate the error of prediction B. determine reliability of the tests C. adjust for initial differences within the groups D. test whether two groups differ significantly

D. test whether two groups differ significantly