- Text
- Variance,
- Population,
- Analysis,
- Estimated,
- Estimate,
- Sizes,
- Scores,
- Dividing,
- Cutoff,
- Participants,
- Statistical,
- Reasoning,
- Psychology

B. medium effect. • C. large effect. • D. None of the above, as there are no standards for **in**terpret**in**g R². Question 24 of 40 2.5/ 2.5 Po**in**ts An analysis of variance differs from a t test for **in**dependent means **in** that an analysis of variance: • A. is usually used to compare two groups, while a t test for **in**dependent means can be used to compare two or more groups. • B. can be used to compare three or more groups, while a t test for **in**dependent means cannot be used to compare more than two groups. • C. is conducted before the experiment, while a t test for **in**dependent means is conducted after the experiment. • D. **in**cludes computation of group variances as part of the analysis, while a t test does not **in**clude these computations. Question 25 of 40 0.0/ 2.5 Po**in**ts When carry**in**g out an analysis of variance with equal sample sizes, the estimated variance of the distribution of means is converted to an estimated variance of the population of **in**dividual scores by: • A. multiply**in**g the estimated variance of the distribution of means by the number of scores **in** each sample. • B. divid**in**g the estimated variance between groups by the number of groups. • C. divid**in**g the estimated variance of the distribution of means by the number of scores **in** each sample. • D. multiply**in**g the estimated variance of the population of **in**dividual scores by the number of groups. Question 26 of 40 2.5/ 2.5 Po**in**ts In an analysis of variance with a with**in**-groups variance estimate of 8.5 and a between-groups variance estimate of 5.3, what is the F ratio? • A. 5.3 / 8.5 = 0.62 • B. 8.5 / 5.3 = 1.60 • C. √5.3 / 8.5 = 0.27 • D. √8.5 / 5.3 = 0.55 Question 27 of 40 2.5/ 2.5 Po**in**ts If a research article does NOT report the variance estimates, R²: • A. can be figured by [(F)(dfBetween.]/[(F)(dfBetween) + dfWith**in**]. •

B. can be figured by F/dfWith**in**. • C. can be estimated by SM/SWith**in**. • D. cannot be figured. Question 28 of 40 2.5/ 2.5 Po**in**ts In an analysis of variance, if the null hypothesis is true, then: • A. the research hypothesis can also be true. • B. fewer participants can be **in**cluded **in** the experiment. • C. there is less variance among means of samples than if the null hypothesis were not true. • D. the with**in**-groups estimate of the population variance is smaller than the between-groups estimate. Question 29 of 40 2.5/ 2.5 Po**in**ts The cutoff F used to evaluate the significance of the Scheffé test for any particular comparison between two group means is • A. the same cutoff F used for the overall study. • B. the cutoff based on df = 1 for the numerator and the overall dfBetween for the denom**in**ator. • C. the cutoff based on df = 2 for the numerator and the overall dfWith**in** for the denom**in**ator. • D. the cutoff based on df = 1 for the numerator and df = overall dfWith**in** / 2 for the denom**in**ator. Question 30 of 40 2.5/ 2.5 Po**in**ts When sample sizes are equal, MSWith**in** is figured by: • A. summ**in**g the population variance estimates figured with**in** each group and divid**in**g by the total number of participants (over all groups). • B. summ**in**g the population variance estimates figured with**in** each group and divid**in**g this sum by the number of groups. • C. multiply**in**g the with**in**-groups sum of squares (SSWith**in**) by the size of each sample (n). • D. divid**in**g the with**in**-groups sum of squares (SSWith**in**) by the size of each sample (n). Question 31 of 40 2.5/ 2.5 Po**in**ts If a research article presented the results of an analysis of variance as, "F (2, 38) = 3.60, p < .05," then how many groups were there **in** the study? •

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