This preview has intentionally blurred sections. Sign up to view the full version.View Full Document
Unformatted text preview: Practice Problems 1. Alex gives an exam in one of the classes he teaches. The maximum possible score is 70. Alex then groups the students by the number of missed lectures, and then obtains a random sample from each of the three groups: students who did not miss any of the lectures, students who missed just a few lectures, and students who missed a lot of lectures. The results are shown in the table below. Lectures Missed None A Few A Lot 64 48 52 57 59 45 67 50 50 70 55 57 54 62 60 62 54 60 n i 7 5 6 i y 62 54.8 53 s i 2 31 34.7 28 a) Does the data suggest that at the average exam scores for these three groups are not the same? State the null and alternative hypotheses, construct an ANOVA table and state your conclusion at α = 0.05 and α = 0.01. b) Use a 95% confidence level and Scheffé’s multiple comparison procedure to compare the average exam score for students who did not miss any of the lectures with the average exam scores for those who missed just a few lectures and those who missed a lot of lectures. lectures and those who missed a lot of lectures....
View Full Document
- Spring '07
- Statistics, Null hypothesis, Statistical hypothesis testing, Error Total