Exam 11: Analysis of Variance: One-Way Classification

Which of these phrases is not like the others; which of these phrases doesn't belong?

When statisticians talk about effect size, they are referring to

The F distribution, as a theoretical distribution,

Data Set 11-6: Walking is valuable exercise. Does the size of the place you live have any relationship to how much walking you do? The following data (in miles per day) are entirely hypothetical, but represent a reasonable guess. (The place names for this problem are ordered from large to small and are from particular sources-can you identify a source or two?) Gotham Middletown Grovers Corners \Sigma 16 24 32 \Sigma 70 60 140 N 4 12 8 -For Data Set 11-6, the number of levels of the independent variable is

Two effect size indexes, f and d, are appropriate for one-way ANOVA data.

The actual amount of difference the independent variable makes is most closely associated with

The larger the population variance, the larger________ is.

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 6b Placebo Low Dose High Dose 12 18 16 8 24 7 15 16 14 13 30 10 6 26 8 7 27 10 Fill in: Independent variable: ____________Dependent variable: __________

The ANOVA technique described in the text can be used on

When the F value calculated from the data of an experiment is larger than the corresponding F value in the table

In a study of the conditions affecting conditioning, four groups of dogs were presented a tone and food powder. The tone, which lasted for four seconds, began eight seconds before the food powder, two seconds before, at the same time the food powder was presented, or two seconds after the food powder was presented. (You might draw a graph of these four conditions as a way of being sure you understand.) The dependent measure was the number of drops of saliva elicited by the tone alone after 50 pairings of the tone and food powder. Group means, an ANOVA summary table and the results of some HSD tests are shown below. Write an interpretation of the results. Conditions Mean Drops of Saliva 8 seconds before 27 2 seconds before 54 simultaneous 14 2 seconds afterward 3 Source df MS F Conditions 3 362.25 7.96 Error 20 45.51 8 vs. 2 seconds before 2 seconds before vs. simultaneous HSD=3.78 HSD=3.60 Simultaneous vs. 2 seconds afterward HSD=1.85

Which of the following is(are) not true?

Many organized groups publish a newsletter and the catchier the name, the better. These newsletters differ in quality from month to month and also from organization to organization. Newsletters from the following organizations were rated on a scale that ranged from 1 (poor) to 20 (excellent). Perform an ANOVA on the scores and put your calculations into a summary table. Compare the two newsletters with the best and the worst average with a Tukey HSD and an effect size index. Write an interpretation of the data and your analyses. Wildebeast Society "Gnusletter" Executioner's Society "Nooseletter" Reason and Common Sense Society "Nousletter" 18 7 10 14 11 12 13 8 13 6 10

For a one way ANOVA, an effect size (d) that is considered small is

After an ANOVA is calculated and the group means examined, an a priori test is appropriate.

Data Set 11-3: The baseline of each curve represents scores on the dependent variable (just like the curves in the book). -Refer to Data Set 11-3. The null hypothesis is true in Experiment

The proper F value from the F table for $\alpha$ = .05, for an experiment in which the df were 7 for MS_treat and 64 for MS_error, is

For a one way ANOVA, effect size indexes (d) that qualifies as large are

MS_error will be a good estimate of the population variance

Which of the following F values, if obtained from an experiment, would lead to rejecting the null hypothesis if $\alpha$ = .01?