Exam 11: Analysis of Variance: One-Way Classification

In an experiment on imprinting, four groups of ducklings were exposed for an hour to a moving light bulb. Three days later a "tendency to follow"score was obtained for each when the moving light bulb was again presented. Group means, an ANOVA summary table, and the results of some HSD tests are shown below. Write an interpretation of the results. Age When First Exposed Mean Following Score 6. 6.35 15. 8.72 30. 5.21 Source df MS F Ages 2 2.14 5.62 Error 28 0.38 6 vs. 15 15 vs. 30 6 vs. 30 HSD 3.75 4.50 2.21

If the F value obtained from the data is larger than the tabled F value, you should

Data Set 11-7: As you may know, there has been some controversy about who the actual author was of plays we today attribute to Shakespeare. Suppose that three critics gave their judgments as to the likelihood (0 to 100%) that each of the three named below was the actual author. William Shakespeare Christopher Marlow The Duke of Oxford Critic Smythe 75 25 50 Critic Jones 40 10 75 Critic Jonson 90 30 20 -The scores in Data Set 11-7_____________ be analyzed using the techniques in Chapter 11 because

A sum of squares is a mean square divided by degrees of freedom.

post hoc tests are to a prior tests as

Ronald A. Fisher

Data Set 11-7: As you may know, there has been some controversy about who the actual author was of plays we today attribute to Shakespeare. Suppose that three critics gave their judgments as to the likelihood (0 to 100%) that each of the three named below was the actual author. William Shakespeare Christopher Marlow The Duke of Oxford Critic Smythe 75 25 50 Critic Jones 40 10 75 Critic Jonson 90 30 20 -Regardless of your answer to the questions above, the df_error for the numbers in Data Set 11-7 is

"All of the samples in the study came from populations with identical means"is a statement of

A student, having completed Chapter 10 of your text, conducted an experiment comparing apples and oranges for fiber content. An independent samples t test was performed resulting in a value of 2.50. Had the student completed Chapter 11 and performed an ANOVA on her two-group experiment, she would have

According to the problem on suicide in your text, high suicide rates are related to __________rates of national _____________

Data Set 11-4: The baseline of each curve represents scores on the dependent variable (just like the curves in the book). -Refer to Data Set 11-4. The null hypothesis should be rejected for an ANOVA in Experiment

Data Set 11-1: The baseline of each curve represents scores on the dependent variable (just like the curves in the book). -Refer to Data Set 11-1. The denominator of the F ratio would be smallest for an ANOVA on Experiment

An experimental psychologist at a VA hospital obtained approval from the Institutional Review Board to conduct a study of the efficacy of a new drug for treatment of depression. Clinically depressed patients were given a placebo, a low dose, or a high dose of the drug. After 60 days the patients were observed by two outside psychologists who rated several different behaviors (eye contact, posture, verbal output, activity, and such) for degree of depression. A composite score was obtained on each patient, with low scores indicating depression. Perform an ANOVA on the scores below. Construct a summary table. Find the effect size index. Examine the group means and pick one informative comparison and perform a Tukey HSD test and find d. Explain the results without too much statistical jargon. -Data Set 6a Placebo Low Dose High Dose 12 18 16 8 24 7 15 16 14 13 30 10 6 26 8 8 20 10 7 27 Fill in: Independent variable: ____________Dependent variable: __________

Alice Isen looks for factors that affect thinking. In one study, she had three groups of participants work on seven remote associates problems, which require creative thinking. One group prepared for the task by exercising; a second group watched a comedy video; the third group was a control group that simply began work on the problems. The scores below show the number correct for each participant. Perform an ANOVA, compile a summary table, find f, and calculate HSD values. Write an interpretation. Exercise Comedy Control 5 4 4 4 7 2 1 6 1 2 5 1 3 3 3 0 4 2 2 7 0

To compare two means from a three-group data set, use a Tukey Honestly Significant Difference test.

In a one-way ANOVA, the total variability is divided into two portions.