Exam 11: Designing, Conducting, Analyzing, and Interpreting Experiments With More Than Two Groups

Examine the results in Table 1 on p. 384 of the article. In APA-format, explain (in words) the results for Muscularity (F).

If our IV has a strong effect, then the F value should be

In an ANOVA source table, to what do the terms "between groups" and "within groups" refer?

Questions refer to Table 11-2. In this study, 10 children completed a survey regarding their impressions of smokers at age 8 and then again at age 10 and 12. Scores could range from 1 (extreme negative impression of smokers) to 20 (extreme positive impression of smokers). Table 11-2 GROUP MEAN STD DEV STD ERROR 1 (AGE 8) 10 9.70 5.89 1.86 2 (AGE 10) 10 10.40 5.58 1.76 3 (AGE 12) 10 11.80 5.94 1.88 ONEWAY ANOVA: SMOKING by AGE (CORR SAMP) SUM OF MEAN SOURCE SQUARES DF SQUARES F RATIO PROB. AGE 22.87 2 11.43 6.76 .006 SUBJECTS 879.63 9 97.74 34.71 .000 WITHIN CELLS 30.47 18 1.69 TOTAL 932.97 29 POST HOC TEST: Tukey-HSD with significance level .05 * Indicates significant differences shown for pairings 1 2 3 Mean 9.70 Grp 1 10.40 Grp 2 11.80 Grp 3 -Consult Table 11-1. What kind of statistical analysis was conducted?

Ex post facto research uses a __________ independent variable.

In the following study, participants were randomly assigned to receive humanistic therapy, psychodynamic therapy, or behavioral therapy for their depression. Six months after therapy ended, participants' levels of depression were rated on a Likert scale from 1 (not at all depressed) to 15 (extremely depressed). GROUP N MEAN STD DEV STD ERROR 1 (humanistic) 10 5.40 2.17 0.69 2 (psychodynamic) 10 7.50 2.84 0.90 3 (behavioral) 10 5.60 3.13 0.99 ONEWAY ANOVA: THERAPY bY DEPRESSION SUM OF MEAN SOURCE SQUARES DF SQUARES F RATIO PROB. BETWEEN GROUPS 26.87 2 13.73 1.78 .187 WTHIN GROUPS 203.30 27 7.53 TOTAL 230.17 29 POST HOC TEST: Tukey-HSD with significance level .05 * Indicates significant differences shown for pairings G G G r r r p p p 1 2 3 Mean THERAPY 5.40 Grp 1 7.50 Grp 2 5.60 Grp 3 -Write an APA-format conclusion for these results.

What makes "self-discrepancy theory" a theory and not, for instance, a hypothesis?

Which of the following is a disadvantage of using repeated measures in a multiple-group experiment?

The differences among the groups in a multiple-group experiment represent _____________ variability.

In the following study, participants were randomly assigned to receive humanistic therapy, psychodynamic therapy, or behavioral therapy for their depression. Six months after therapy ended, participants' levels of depression were rated on a Likert scale from 1 (not at all depressed) to 15 (extremely depressed). GROUP N MEAN STD DEV STD ERROR 1 (humanistic) 10 5.40 2.17 0.69 2 (psychodynamic) 10 7.50 2.84 0.90 3 (behavioral) 10 5.60 3.13 0.99 ONEWAY ANOVA: THERAPY bY DEPRESSION SUM OF MEAN SOURCE SQUARES DF SQUARES F RATIO PROB. BETWEEN GROUPS 26.87 2 13.73 1.78 .187 WTHIN GROUPS 203.30 27 7.53 TOTAL 230.17 29 POST HOC TEST: Tukey-HSD with significance level .05 * Indicates significant differences shown for pairings G G G r r r p p p 1 2 3 Mean THERAPY 5.40 Grp 1 7.50 Grp 2 5.60 Grp 3 -Did the independent variable have a significant effect on the dependent variable? How do you know?

A researcher was interested in determining the effectiveness of humanistic therapy for alleviating depression. He administered a depression inventory to a sample of clients with depression on three occasions: before therapy started, two months after therapy began, and four months into therapy. Depression scores could range from 1 (not at all depressed) to 15 (extremely depressed). GROUP MEAN STD DEV STD ERROR 1 (Time 1) 10 13.50 1.58 0.50 2 (Time 2) 10 9.40 2.88 0.91 3 (Time 3) 10 7.30 4.06 1.28 $\text { ONEWAY ANOVA: DEPRESSION by TIME (CORR SAMP) }$ SUM OF MEAN SOURCE SQUARES DF SQUARES F RATIO PROB. TIME 198.87 2 99.43 18.43 .000 SUBJECTS 147.88 9 16.43 185.04 .000 WITHIN CELLS 97.13 18 5.40 TOTAL 443.88 29 POST HOC TEST: Tukey-HSD with significance level .05 * Indicates significant differences shown for pairings G G G r r r p p p 1 2 3 Mean TIME 13.50 Grp 1 9.40 Grp 2 7.30 Grp 3 -Why does "DF Clothing" = 2?

What is one way to operationally define "casual clothing" in an experiment in which you manipulate the type of clothing customers where to a store?

What is one limitation of using natural sets in a multiple-group design?

A researcher was interested in determining the effectiveness of humanistic therapy for alleviating depression. He administered a depression inventory to a sample of clients with depression on three occasions: before therapy started, two months after therapy began, and four months into therapy. Depression scores could range from 1 (not at all depressed) to 15 (extremely depressed). GROUP MEAN STD DEV STD ERROR 1 (Time 1) 10 13.50 1.58 0.50 2 (Time 2) 10 9.40 2.88 0.91 3 (Time 3) 10 7.30 4.06 1.28 $\text { ONEWAY ANOVA: DEPRESSION by TIME (CORR SAMP) }$ SUM OF MEAN SOURCE SQUARES DF SQUARES F RATIO PROB. TIME 198.87 2 99.43 18.43 .000 SUBJECTS 147.88 9 16.43 185.04 .000 WITHIN CELLS 97.13 18 5.40 TOTAL 443.88 29 POST HOC TEST: Tukey-HSD with significance level .05 * Indicates significant differences shown for pairings G G G r r r p p p 1 2 3 Mean TIME 13.50 Grp 1 9.40 Grp 2 7.30 Grp 3 -What is the dependent variable in this study?

Questions refer to Table 11-2. In this study, 10 children completed a survey regarding their impressions of smokers at age 8 and then again at age 10 and 12. Scores could range from 1 (extreme negative impression of smokers) to 20 (extreme positive impression of smokers). Table 11-2 GROUP MEAN STD DEV STD ERROR 1 (AGE 8) 10 9.70 5.89 1.86 2 (AGE 10) 10 10.40 5.58 1.76 3 (AGE 12) 10 11.80 5.94 1.88 ONEWAY ANOVA: SMOKING by AGE (CORR SAMP) SUM OF MEAN SOURCE SQUARES DF SQUARES F RATIO PROB. AGE 22.87 2 11.43 6.76 .006 SUBJECTS 879.63 9 97.74 34.71 .000 WITHIN CELLS 30.47 18 1.69 TOTAL 932.97 29 POST HOC TEST: Tukey-HSD with significance level .05 * Indicates significant differences shown for pairings 1 2 3 Mean 9.70 Grp 1 10.40 Grp 2 11.80 Grp 3 -Consult Table 11-2. The SUBJECTS effect is significant, which means that

Describe the matched sets approach to creating multiple-correlated groups and give an example.

Any variability that is not a product of the independent variable is known as ________ variability.

In the following study, participants were randomly assigned to receive humanistic therapy, psychodynamic therapy, or behavioral therapy for their depression. Six months after therapy ended, participants' levels of depression were rated on a Likert scale from 1 (not at all depressed) to 15 (extremely depressed). GROUP N MEAN STD DEV STD ERROR 1 (humanistic) 10 5.40 2.17 0.69 2 (psychodynamic) 10 7.50 2.84 0.90 3 (behavioral) 10 5.60 3.13 0.99 ONEWAY ANOVA: THERAPY bY DEPRESSION SUM OF MEAN SOURCE SQUARES DF SQUARES F RATIO PROB. BETWEEN GROUPS 26.87 2 13.73 1.78 .187 WTHIN GROUPS 203.30 27 7.53 TOTAL 230.17 29 POST HOC TEST: Tukey-HSD with significance level .05 * Indicates significant differences shown for pairings G G G r r r p p p 1 2 3 Mean THERAPY 5.40 Grp 1 7.50 Grp 2 5.60 Grp 3 -How could you change this experiment to be a repeated measures design?

Daisy conducts a study in which a sample of rats receives a high dose of alcohol on one day, a low dose of alcohol on one day, and no alcohol on one day. Each day, she measures the time it takes them to learn a new maze. What statistical technique should Daisy use to analyze her data?

If a researcher has used random assignment, then