Exam 9: Introduction to the Analysis of Variance

Advanced topic: A social psychologist conducted a study to see if sales approach made a difference in the number of raffle tickets sold.Using the norm of reciprocity (giving buyers a free gift),3,1,and 2 tickets were sold; using the foot-in-the-door approach (getting buyers to agree to buy one ticket first,then more),3,3,and 3 tickets were sold; and using no special technique,1,0,1,and 2 tickets were sold.Using the .05 level,does sales technique make a difference in number of tickets sold? a.Carry out the five steps of hypothesis testing and make a complete analysis of variance table. b.Sketch the distributions involved. c.Figure the effect size of this study and indicate whether it is nearer to small,medium,or large. d.Explain the logic of what you did to a person who is familiar with the analysis of variance using the approach in which you figure the variance for each group,but who has not learned anything about the structural model approach.(Be sure to explain dividing the overall deviation from the grand mean,the logic of the different parts of the analysis of variance table,and how all this relates to the logic of the approach in which you figure the variance for each group.)

Which statistical procedure ensures that the alpha level for any given planned contrast will not exceed .05?

A planned comparison comparing two means involves figuring an F ratio in which the numerator

A characteristic of an F ratio is that